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Journal articles on the topic 'Composés carbonylés'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 May 2024

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1

Aussems, C., S. Jaspers, G. Leroy, and F. van Remoortere. "Étude théorique des systèmes hétéroatomiques conjugués. III. les composés carbonylés." Bulletin des Sociétés Chimiques Belges 78, no. 9-10 (September 2, 2010): 487–93. http://dx.doi.org/10.1002/bscb.19690780907.

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2

Troupel, Michel, Maiténa Oçafrain, Eric Dolhem, Jean-Claude Folest, and Rachid Barhdadi. "Electrosynthéses de composés carbonylés catalysées par des complexes du nickel: Activation du monoxyde de carbone ou de composés acylés." Canadian Journal of Chemical Engineering 76, no. 6 (December 1998): 1013–19. http://dx.doi.org/10.1002/cjce.5450760607.

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3

Hofer, Roger, Daniel Evard, and André Jacot-Guillarmod. "Reactivité de composés carbonylés avec des cétènes en présence d'alkoxydes de titane ou de zirconium. 3e communication." Helvetica Chimica Acta 68, no. 4 (June 26, 1985): 969–74. http://dx.doi.org/10.1002/hlca.19850680422.

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4

Fournier, Françoise, and Michel Fournier. "Transferts d'électrons assistés par les métaux de transition:influence de la nature du cation métallique sur la réduction de composés carbonylés en milieu aprotique." Canadian Journal of Chemistry 64, no. 5 (May 1, 1986): 881–90. http://dx.doi.org/10.1139/v86-146.

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The pinacolisation of ketones is enhanced when a bivalent transition metal cation is present. This phenomenon is general and occurs with Cr2+, Mn2+, Fe2+, Co2+, Zn2+ but not with Ni2+. The cathodic reduction leads to α-glycols with a good yield, without any resin production, and at a less negative potential than that of the ketone itself. The distribution of all isolated compounds is dependent on the Lewis character-acidity and complexing power of the metallic cation. Thus, for the dimerization, the greatest specificity is generally observed when Fe2+ is present. For the chalcone, the better stereoselectivity is obtained with Zn2+. No evidence of initial carbonyl complex of the metal ion was shown.

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5

Bernard, Didier, Alain Doutheau, and Jacques Gore. "Nouvelle voie d'acces aux composes carbonyles α- alleniques." Tetrahedron 43, no. 12 (January 1987): 2721–32. http://dx.doi.org/10.1016/s0040-4020(01)86877-0.

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6

Guiheneuf, Georges, José-Luis M. Abboud, and Widded Bouab. "Effets de solvant sur les complexes par transfert de charge iode – composés thiocarbonylés." Canadian Journal of Chemistry 65, no. 9 (September 1, 1987): 2106–8. http://dx.doi.org/10.1139/v87-349.

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The effects of solvents on different iodine – thiocarbonyl base charge-transfer complexes of variable stability have been examined and these are compared with the effects of solvents of the iodine – carbonyl compound complexes. There is an inversion of the effect of those solvents that can form hydrogen bonds on going from one series to the other, which is attributed to the fact that the carbonyl compounds are hard bases while the thiocarbonyl compounds are soft bases. [Journal translation]

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7

Schneider, M., M. J. Gil, A. Reliquet, J. C. Meslin, J. Levillain, M. Vazeux, D. Jury, J. L. Mieloszynski, and D. Paquer. "Correlations Des DéPlacements Chimiques En Rmn 13C De ComposéS Carbonyles, Thiocarbonyles Et Selenocarbonyles." Phosphorus, Sulfur, and Silicon and the Related Elements 134, no. 1 (February 1, 1998): 295–305. http://dx.doi.org/10.1080/10426509808545470.

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8

Thuy, Vu Moc. "Utilisation du Chromate Imprégné Sur Alumine Pour L'Oxydation des Dérivés Halogènes En Composés Carbonyles." Bulletin des Sociétés Chimiques Belges 102, no. 4 (September 1, 2010): 299–300. http://dx.doi.org/10.1002/bscb.19931020413.

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9

Thuy, Vu Moc, and Pierre Maitte. "Utilisation Du Permanganate Impregne Sur Alumine Pour L'Oxydation Des Alcools En Composes Carbonyles." Bulletin des Sociétés Chimiques Belges 98, no. 11 (September 1, 2010): 877–78. http://dx.doi.org/10.1002/bscb.19890981110.

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10

Marques, Marcelo Volpatto, Denis Russowsky, and L. M. A. Fontoura. "ANÁLISE CONFORMACIONAL DE COMPOSTOS DE BIGINELLI COM ATIVIDADE ANTINEOPLÁSICA." Eclética Química Journal 35, no. 4 (January 22, 2018): 33. http://dx.doi.org/10.26850/1678-4618eqj.v35.4.2010.p33-38.

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Dihydropyrimidinones, such as monastrol and analogues, are heterocycles with known antineoplastic activity. Conformational analysis represents an important preliminary step in structure-activity correlation studies. Herein we describe the conformational analysis of monastrol and analogues by AM1 semiempirical and ab initio HF/6-31G* calculations. Four equilibrium geometries were found (s-cis/ap, s-cis/sp, strans/ap and s-trans/sp), and the important internal rotations were those of the ab-unsaturated carbonyl system and of the aryl group connected to the heterocycle

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11

Mabato, Beatrix Rosette Go, Yan Lyu, Yan Ji, Yong Jie Li, Dan Dan Huang, Xue Li, Theodora Nah, Chun Ho Lam, and Chak K. Chan. "Aqueous secondary organic aerosol formation from the direct photosensitized oxidation of vanillin in the absence and presence of ammonium nitrate." Atmospheric Chemistry and Physics 22, no. 1 (January 10, 2022): 273–93. http://dx.doi.org/10.5194/acp-22-273-2022.

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Abstract. Vanillin (VL), a phenolic aromatic carbonyl abundant in biomass burning emissions, forms triplet excited states (3VL∗) under simulated sunlight leading to aqueous secondary organic aerosol (aqSOA) formation. Nitrate and ammonium are among the main components of biomass burning aerosols and cloud or fog water. Under atmospherically relevant cloud and fog conditions, solutions composed of either VL only or VL with ammonium nitrate were subjected to simulated sunlight irradiation to compare aqSOA formation via the direct photosensitized oxidation of VL in the absence and presence of ammonium nitrate. The reactions were characterized by examining the VL decay kinetics, product compositions, and light absorbance changes. Both conditions generated oligomers, functionalized monomers, and oxygenated ring-opening products, and ammonium nitrate promoted functionalization and nitration, likely due to its photolysis products (⚫OH, ⚫NO2, and NO2- or HONO). Moreover, a potential imidazole derivative observed in the presence of ammonium nitrate suggested that ammonium participated in the reactions. The majority of the most abundant products from both conditions were potential brown carbon (BrC) chromophores. The effects of oxygen (O2), pH, and reactants concentration and molar ratios on the reactions were also explored. Our findings show that O2 plays an essential role in the reactions, and oligomer formation was enhanced at pH <4. Also, functionalization was dominant at low VL concentrations, whereas oligomerization was favored at high VL concentrations. Furthermore, oligomers and hydroxylated products were detected from the oxidation of guaiacol (a non-carbonyl phenol) via VL photosensitized reactions. Last, potential aqSOA formation pathways via the direct photosensitized oxidation of VL in the absence and presence of ammonium nitrate were proposed. This study indicates that the direct photosensitized oxidation of VL may be an important aqSOA source in areas influenced by biomass burning and underscores the importance of nitrate in the aqueous-phase processing of aromatic carbonyls.

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12

Brunner, Henri, Dominique Lucas, Teresa Monzon, Yves Mugnier, Bernhard Nuber, Bernhard Stubenhofer, A. Claudia Stückl, Joachim Wachter, Robert Wanninger, and Manfred Zabel. "Metal Telluride Clusters Composed of Niobocene Carbonyl, Telluride, and Cobalt Carbonyl Units: Syntheses, Structures, and Reactivity." Chemistry - A European Journal 6, no. 3 (February 4, 2000): 493–503. http://dx.doi.org/10.1002/(sici)1521-3765(20000204)6:3<493::aid-chem493>3.0.co;2-e.

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13

Chumakova, Natalia, and Alexander Kokorin. "Graphene Oxide Membranes—Synthesis, Properties, and Applications." Membranes 13, no. 9 (August 31, 2023): 771. http://dx.doi.org/10.3390/membranes13090771.

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14

Fucikova, Anna, Ilya Sychugov, and Jan Linnros. "The shell matters: one step synthesis of core–shell silicon nanoparticles with room temperature ultranarrow emission linewidth." Faraday Discussions 222 (2020): 135–48. http://dx.doi.org/10.1039/c9fd00093c.

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15

Vázquez-Vuelvas, Oscar F., René A. Enríquez-Figueroa, Héctor García-Ortega, Marcos Flores-Alamo, and Armando Pineda-Contreras. "Crystal structure of the chalcone (E)-3-(furan-2-yl)-1-phenylprop-2-en-1-one." Acta Crystallographica Section E Crystallographic Communications 71, no. 2 (January 17, 2015): 161–64. http://dx.doi.org/10.1107/s205698901500047x.

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The title chalcone derivative, C13H10O2, adopts anEconformation about the C=C double bond. The molecule is composed of a furanyl and a phenyl ring, bridged by an α,β-unsaturated carbonyl system, which are inclined to one another by 24.07 (7)°. In the crystal, molecules are connected by weak C—H...O hydrogen bonds involving the carbonyl O atom acting as a trifurcated acceptor and C—H...π interactions, forming ribbons extending along thec-axis direction.

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16

Li, W. D., Ming Lv, and Sheng Qiang Yang. "Preliminary Research on the Post Treatment of Fluid Magnetic Abrasivetool." Key Engineering Materials 455 (December 2010): 161–64. http://dx.doi.org/10.4028/www.scientific.net/kem.455.161.

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Fluid magnetic abrasivetool(FMA) is one kind of latest finishing abrasivetool which is a sort of suspended fluid composed by magnetic particles, nonmagnetic abrasive particles, surfactants in a non-magnetizable carrier liquid. After a period of working time, the performance-life of the abrasivetool ended because of the cutting- blade of the abrasives particles being passive. While the most costly component- the magnetic particles (carbonyl iron particles) can be reused. This paper has made up two recovery flows to separated carbonyl iron particles from others.

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17

GONG, X. L., L. CHEN, and J. F. LI. "STUDY OF UTILIZABLE MAGNETORHEOLOGICAL ELASTOMERS." International Journal of Modern Physics B 21, no. 28n29 (November 10, 2007): 4875–82. http://dx.doi.org/10.1142/s0217979207045785.

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This paper presents two kinds of magnetorheological elastomers (MREs). One is composed of appropriate silicon rubber, carbonyl iron particles and some other materials. It is cured under a strong magnetic field at a room temperature. Its shear modulus change from 0.34MPa at zero magnetic field to 3.34MPa at 1T magnetic field, the relative MR effect reaches 878%. Such high MR effect has not been reported until now. The other is composed by appropriate natural rubber, carbonyl iron particles and some other materials. After the compositions are mixed in a two-roll mill, they are cured under a strong magnetic field according to a temperature profile. The increment of its modulus reaches 3.6MPa, and the relative modulus increment is 133%. Their mechanical properties are also evaluated. All observed results show that the fabricated MREs are utilizable. They have successfully been utilized to adaptive tuned vibration absorbers, which will serve for vibration absorption of vehicles.

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18

Flament, Ivon, Philippe Sonnay, and Günther Ohloff. "Pyrazines III Condensation Des Dihydropyrazines Avec Les Composés Carbonyles: Synthèse De Pyrazines Substituées Et De Dihydro-6, 7-5E-Cyclopenta [b] pyrazines." Bulletin des Sociétés Chimiques Belges 88, no. 11 (September 1, 2010): 941–50. http://dx.doi.org/10.1002/bscb.19790881115.

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19

Zhuang, Hai-Yan, Xiao-Kun Wang, Zhi-Ming Ye, Yi Yang, Dong-Ming Tang, Bao-Shan Zhang, Cong-Shu Huang, and Jing-Jing Wang. "Research on Broadband Microwave Absorber Containing a 2D Artificial Electromagnetic Material Composed of Cross Section Resonator Sub-Unit Cells Inserting Ferromagnetic Materials." Journal of Nanoelectronics and Optoelectronics 15, no. 1 (January 1, 2020): 108–12. http://dx.doi.org/10.1166/jno.2020.2720.

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This paper provides a new method to improve microwave absorption properties of ferromagnetic materials. A 2D artificial electromagnetic material is designed using a square combination of cross section resonator sub-unit cells, and then inserted into carbonyl iron powder layers to realize a broadband microwave absorber. Both the simulation and experiment results show that the absorber can realize the wideband and high efficiency absorption.

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20

Thuy, Vu Moc, and Pierre Maitte. "Sur L'Utilisation De L'Ion Chromate Comme Agent Oxydant Dans La Synthese De Composes Carbonyles A Partir De Derives Halogenes Actives." Bulletin des Sociétés Chimiques Belges 98, no. 3 (September 1, 2010): 221–22. http://dx.doi.org/10.1002/bscb.19890980310.

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21

Orentas, Edvinas, Ola F. Wendt, Kenneth Wärnmark, Eugenijus Butkus, and Carl-Johan Wallentin. "rac-4,8-Divinylbicyclo[3.3.1]nonane-2,6-dione." Acta Crystallographica Section E Structure Reports Online 65, no. 6 (May 20, 2009): o1357. http://dx.doi.org/10.1107/s1600536809018443.

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The title compound, C13H16O2, is a chiral bicyclic structure composed of two fused cyclohexane rings possessing both boat and chair conformations. The molecules are packed in enantiopure columns which are pairwise linked forming an overall racemic solid; within the column pairs the packing is governed by weak dipole–dipole interactions stemming from stacked carbonyl functionalities (COcentroid–COcentroiddistance = 3.290 Å).

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22

Jiang, Lin, Qiang Xu, and Chun Pu Hu. "Preparation and Characterization of Waterborne Polyurethaneurea Composed of Dimer Fatty Acid Polyester Polyol." Journal of Nanomaterials 2006 (2006): 1–10. http://dx.doi.org/10.1155/jnm/2006/14906.

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A series of polyurethaneurea (PUU) aqueous dispersions, which were stable at ambient temperature for more than 1 year, were prepared with C36-dimer-fatty-acid-based polyester polyol, isophorone diisocyanate, dimethylol propionic acid, and ethylenediamine. The particle size of all these PUU (DPU) aqueous dispersions (<100nm) was less than that of comparable specimens, that is, poly-(neopentyl glycol adipate) polyester-polyol-based PUU (APU) aqueous dispersions, and the polydispersity index was very narrow (≤1.13). The films prepared with the DPU aqueous dispersions exhibited excellent waterproof performance, such as low amount of water absorption (1.3 wt%), and good mechanical properties (hardness and tensile strength), resulting from the strong hydrogen bonding in urea carbonyl groups and the perfect ordered structure of hard segments compared with those prepared with the APU aqueous dispersions. The surface hydrophobicity of the films prepared with modified DPU aqueous dispersions, which were modified with a fluorinated polyacrylate emulsion, was excellent, as the water contact angle on the surface of such films rose up to 100. The mechanical properties of such modified DPU films were further enhanced.

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23

Harris, Michael, Bridget K. Stein, John H. P. Tyman, and Christopher M. Williams. "The Structure of the Colourant/Pigment, Carmine Derived from Carminic Acid." Journal of Chemical Research 2009, no. 7 (July 2009): 407–9. http://dx.doi.org/10.3184/030823409x460768.

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The colourant/pigment carmine synthesised from carminic acid and calcium and aluminium acetates has been examined chemically and spectroscopically to determine its structure. As with alizarin, it appears probable that the material is a tetramer but composed of four carminic acid units with aluminium involved with the 5,6-dioxy groups in five-membered rings and calcium chelated with the 10-carbonyl group of the anthraquinone system.

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24

Alves, Célia, Ana Vicente, Ana Rita Oliveira, Carla Candeias, Estela Vicente, Teresa Nunes, Mário Cerqueira, Margarita Evtyugina, Fernando Rocha, and Susana Marta Almeida. "Fine Particulate Matter and Gaseous Compounds in Kitchens and Outdoor Air of Different Dwellings." International Journal of Environmental Research and Public Health 17, no. 14 (July 21, 2020): 5256. http://dx.doi.org/10.3390/ijerph17145256.

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Passive diffusion tubes for volatile organic compounds (VOCs) and carbonyls and low volume particulate matter (PM2.5) samplers were used simultaneously in kitchens and outdoor air of four dwellings. PM2.5 filters were analysed for their carbonaceous content (organic and elemental carbon, OC and EC) by a thermo-optical technique and for polycyclic aromatic hydrocarbon (PAHs) and plasticisers by GC-MS. The morphology and chemical composition of selected PM2.5 samples were characterised by SEM-EDS. The mean indoor PM2.5 concentrations ranged from 14 µg m−3 to 30 µg m−3, while the outdoor levels varied from 18 µg m−3 to 30 µg m−3. Total carbon represented up to 40% of the PM2.5 mass. In general, the indoor OC/EC ratios were higher than the outdoor values. Indoor-to-outdoor ratios higher than 1 were observed for VOCs, carbonyls and plasticisers. PAH levels were much higher in the outdoor air. The particulate material was mainly composed of soot aggregates, fly ashes and mineral particles. The hazard quotients associated with VOC inhalation suggested a low probability of non-cancer effects, while the cancer risk was found to be low, but not negligible. Residential exposure to PAHs was dominated by benzo[a]pyrene and has shown to pose an insignificant cancer risk.

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25

Mabato, Beatrix Rosette Go, Yong Jie Li, Dan Dan Huang, Yalin Wang, and Chak K. Chan. "Comparison of aqueous secondary organic aerosol (aqSOA) product distributions from guaiacol oxidation by non-phenolic and phenolic methoxybenzaldehydes as photosensitizers in the absence and presence of ammonium nitrate." Atmospheric Chemistry and Physics 23, no. 4 (March 2, 2023): 2859–75. http://dx.doi.org/10.5194/acp-23-2859-2023.

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Abstract. Aromatic carbonyls (e.g., methoxybenzaldehydes), an important class of photosensitizers, are abundant in the atmosphere. Photosensitization and nitrate-mediated photo-oxidation can occur simultaneously, yet studies about their interactions, particularly for aqueous secondary organic aerosol (aqSOA) formation, remain limited. This study compared non-phenolic (3,4-dimethoxybenzaldehyde, DMB) and phenolic (vanillin, VL) methoxybenzaldehydes as photosensitizers for aqSOA formation via guaiacol (GUA) oxidation in the absence and presence of ammonium nitrate (AN) under atmospherically relevant cloud and fog conditions. GUA oxidation by triplet excited states of DMB (3DMB∗) (GUA + DMB) was ∼ 4 times faster and exhibited greater light absorption than oxidation by 3VL∗ (GUA + VL). Both GUA + DMB and GUA + VL formed aqSOA composed of oligomers, functionalized monomers, oxygenated ring-opening species, and N-containing products in the presence of AN. The observation of N-heterocycles such as imidazoles indicates the participation of ammonium in the reactions. The majority of generated aqSOA comprises potential brown carbon (BrC) chromophores. Oligomerization and functionalization dominated in GUA + DMB and GUA + VL, but functionalization appeared to be more important in GUA + VL due to contributions from VL itself. AN did not significantly affect the oxidation kinetics, but it had distinct effects on the product distributions, likely due to differences in the photosensitizing abilities and structural features of DMB and VL. In particular, the more extensive fragmentation in GUA + DMB than in GUA + VL likely generated more N-containing products in GUA + DMB + AN. In GUA + VL + AN, the increased oligomers may be due to VL-derived phenoxy radicals induced by ⚫OH or ⚫NO2 from nitrate photolysis. Furthermore, increased nitrated products observed in the presence of both DMB or VL and AN than in AN alone imply that photosensitized reactions may promote nitration. This work demonstrates how the structural features of photosensitizers affect aqSOA formation via non-carbonyl phenol oxidation. Potential interactions between photosensitization and AN photolysis were also elucidated. These findings facilitate a better understanding of photosensitized aqSOA formation and highlight the importance of AN photolysis in these reactions.

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26

Si, Wenhao, Fei Qi, Kangjun Wang, Qiang Wang, Zequan Zeng, Yuting Niu, and Zhanggen Huang. "Modified Gasification-Slag-Driven Persulfate Activation for Highly Efficient Degradation of Acetaminophen: N/O Active Site Regulation and Nonradical Oxidation." Catalysts 13, no. 12 (December 15, 2023): 1512. http://dx.doi.org/10.3390/catal13121512.

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With the development of coal chemical technology, a large amount of gasification slag and wastewater are produced through coal gasification. Efficient gasification slag utilization and wastewater treatment have attracted much attention. In this study, gasification slag was modified and used as a low-cost and efficient catalyst to activate persulfate for acetaminophen degradation. Via the analysis of high-resolution X-ray photoelectron spectroscopy, the surfaces of nitric acid and calcined modified gasification slag retained a considerable number of carbonyl and graphite N functional groups. These proved to be effective active sites for the activation of persulfate. X-ray diffraction analysis revealed that the gasification slag was composed of carbon and SiO2. The evaluation of catalytic activity and application of density functional theory proved that the interaction between carbonyl and graphitic nitrogen significantly affected the catalyst activity. When the ratio of graphitic nitrogen to carbonyl was 1:3, the adsorption and activation of persulfate were significantly enhanced. The results of the quenching experiments also confirmed that the non-free radical pathway is the main pathway to activate persulfate using the gasification slag. This study provides a new approach to industrial waste utilization in wastewater treatment.

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27

Andrade, L. C. R., J. A. Paixão, M. J. M. de Almeida, E. J. Tavares da Silva, and F. M. Fernandes Roleira. "N-Hexyl-3-(4-hydroxy-3,5-dimethoxyphenyl)propanamide." Acta Crystallographica Section E Structure Reports Online 68, no. 6 (May 2, 2012): o1603—o1604. http://dx.doi.org/10.1107/s1600536812019022.

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In the title compound, C17H27NO4, which is an hydrosinapic acid derivative with increased lipophilicity conferred by an additional alkyl chain, the central and the hexyl linear chains contain slightly shorter bond lengths [C—N = 1.316 (2) Å; average linear chain C—C = 1.487 (6) Å] than reported average values [Csp 2—N = 1.334, C—C for CH2—CH2 = 1.524 and 1.513 Å for CH2—CH3]. The 4-hydroxy-3,5-dimethoxyphenyl plane [r.m.s. deviation 0.055 (12) Å] makes an angle of 59.89 (5)° with the central plane of the molecule (composed of the N atom, the carbonyl group and the two methylene C atoms linking the carbonyl group and the ring, [r.m.s. deviation 0.0026 (10) Å], which, in turn, makes an angle of 64.24 (13)° with the essentially planar hexyl chain [r.m.s. deviation 0.035 (18) Å]. The N—H group of the amide group is involved in a bifurcated hydrogen bond towards the hydroxy and one of the methoxy O atoms of the 4-hydroxy-3,5-dimethoxyphenyl substituent of a neighbouring molecule, forming a two-dimensional network in the (100) plane. In addition, the same hydroxy group acts as a donor towards the carbonyl O atom of another neighbouring molecule, forming chains running along the b axis.

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28

Wang, Zhiming, Congna Wang, Weiliang Bao, and Taokei Ying. "Task-specific Ionic Liquids as Efficient, Green and Recyclable Reagents and Solvents for Oxidation of Olefins." Journal of Chemical Research 2005, no. 6 (June 2005): 388–90. http://dx.doi.org/10.3184/0308234054506758.

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Two kinds of task-specific ionic liquids (Ils) composed of imidazolinium or pyridinium cations with a carboxy group and hydrogensulfate as counterion have been synthesised and their application in oxidation of olefins has been studied. The carbonyl compounds were obtained from the oxidation of chain olefins, and 1,2-cycloalkandiols were obtained from cycloalkenes in the novel oxidation systems which are easily manipulated. The products can be easily isolated from the reaction system and the ILs can readily be recovered and reused.

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29

Zhou, Bi-Cheng, Dong-Hong Wang, Bao-Yi Li, Ya-Juan Zhao, Jiang-Jiang Ma, and Ke-Xun Li. "Effect of the circular microstructure on absorbing properties of carbonyl iron rubber radar absorbing patch." International Journal of Modern Physics B 33, no. 01n03 (January 30, 2019): 1940049. http://dx.doi.org/10.1142/s0217979219400496.

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A kind of radar absorber is designed and produced based on circular microstructure, which is composed of a circular microstructure, carbonyl iron rubber radar absorbing patch and metal backboard composition. Numerical simulation of effect of the circular microstructure on absorbing properties of carbonyl iron rubber radar absorbing patch is performed by means of the time domain finite integral method. Simulated results indicate that by using the holding absorber with the unchanged thickness of 2.5 mm, when the absorber unit size was P = 30 mm and the circular radius was R = 5 mm, the value of the minimum absorption peak can reach −43 dB, −10 dB absorption band shifted from 5.8–9.3 to 4.6–8.2 GHz, changing the parameters of circular microstructure greatly, expanding the absorbing bandwidth of microwave absorbing patch, reducing the reflectivity of resonance frequency. According to the simulation results, the samples are prepared and tested. The test results are in agreement with the simulation results.

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30

Vellora Thekkae Padil, Vinod, Nhung H. A. Nguyen, Alena Ševců, and Miroslav Černík. "Fabrication, Characterization, and Antibacterial Properties of Electrospun Membrane Composed of Gum Karaya, Polyvinyl Alcohol, and Silver Nanoparticles." Journal of Nanomaterials 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/750726.

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Gum karaya (GK), a natural hydrocolloid, was mixed with polyvinyl alcohol (PVA) at different weight ratios and electrospun to produce PVA/GK nanofibers. An 80 : 20 PVA/GK ratio produced the most suitable nanofiber for further testing. Silver nanoparticles (Ag-NPs) were synthesised through chemical reduction of AgNO3(at different concentrations) in the PVA/GK solution, the GK hydroxyl groups being oxidised to carbonyl groups, and Ag+cations reduced to metallic Ag-NPs. These PVA/GK/Ag solutions were then electrospun to produce nanofiber membranes containing Ag-NPs (Ag-MEMs). Membrane morphology and other characteristics were analysed using scanning electron microscopy coupled with energy dispersive X-ray analysis, transmission electron microscopy, and UV-Vis and ATR-FTIR spectroscopy. The antibacterial activity of the Ag-NP solution and Ag-MEM was then investigated against Gram-negativeEscherichia coliandPseudomonas aeruginosaand Gram-positiveStaphylococcus aureus. Our results show that electrospun nanofiber membranes based on natural hydrocolloid, synthetic polymer, and Ag-NPs have many potential uses in medical applications, food packaging, and water treatment.

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31

Pakulski, Zbigniew, Norbert Gajda, Magdalena Jawiczuk, Jadwiga Frelek, Piotr Cmoch, and Sławomir Jarosz. "Synthesis of a sucrose dimer with enone tether; a study on its functionalization." Beilstein Journal of Organic Chemistry 10 (May 28, 2014): 1246–54. http://dx.doi.org/10.3762/bjoc.10.124.

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The reaction of appropriately functionalized sucrose phosphonate with sucrose aldehyde afforded a dimer composed of two sucrose units connected via their C6-positions (‘the glucose ends’). The carbonyl group in this product (enone) was stereoselectively reduced with zinc borohydride and the double bond (after protection of the allylic alcohol formed after reduction) was oxidized with osmium tetroxide to a diol. Absolute configurations of the allylic alcohol as well as the diol were determined by circular dichroism (CD) spectroscopy using the in situ dimolybdenum methodology.

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Aldini, Giancarlo, and Alessandra A. Altomare. "Reactive Carbonyl Species and Protein Adducts: Identification Strategies, Biological Mechanisms and Molecular Approaches for Their Detoxification." Antioxidants 10, no. 5 (April 28, 2021): 690. http://dx.doi.org/10.3390/antiox10050690.

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Leonowicz, Marcin, Joanna Kozłowska, and Łukasz Wierzbicki. "Rheological Fluids for Energy Absorbing Systems." Applied Mechanics and Materials 440 (October 2013): 13–18. http://dx.doi.org/10.4028/www.scientific.net/amm.440.13.

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Two types of non-Newtonian fluids, magneto rheological (MRF) and shear thickening (STF) fluids, respectively were chosen as candidates for energy dissipation study in smart body armour. A series of magneto rheological fluids was synthesized on a basis of synthetic oil and carbonyl iron. The shear modules for the MRF containing 75 wt% of carbonyl iron, obtained in a magnetic field of 230 kA/m were as follows: complex shear modulus G* - 1.2 MPa, storage modulus G-1.2 MPa and loss modulus G 0.35 MPa. The studies revealed also that the silica fumed, dispersed in polypropylene glycol or polyethylene oxide, demonstrates shear thickening properties. The best combination of the properties (high viscosity, obtained at high shear rate) represents the material composed of the silica fumed (SF) and PEO300. Change of the volume fraction of the SF and variation of the molecular weight of the oligomer enables tailoring of the STF properties. Ballistic tests revealed that the structures containing PE bags with MRF (in magnetic field) or STF can enhance the protective performance of body armours providing their flexibility.

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Lim, Jun-Hee, Yo-Han Ryu, and Sung-Soo Kim. "Dual-band microwave absorption properties of metamaterial absorber composed of split ring resonator on carbonyl iron powder composites." Electronic Materials Letters 11, no. 3 (May 2015): 447–51. http://dx.doi.org/10.1007/s13391-015-4358-9.

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35

Janecka, J., M. B. Jenkins, N. S. Brackett, L. W. Lion, and W. C. Ghiorse. "Characterization of a Sinorhizobium Isolate and Its Extracellular Polymer Implicated in Pollutant Transport in Soil." Applied and Environmental Microbiology 68, no. 1 (January 2002): 423–26. http://dx.doi.org/10.1128/aem.68.1.423-426.2002.

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ABSTRACT A bacterium isolated from soil (designated 9702-M4) synthesizes an extracellular polymer that facilitates the transport of such hydrophobic pollutants as polynuclear aromatic hydrocarbons, as well as the toxic metals lead and cadmium in soil. Biolog analysis, growth rate determinations, and percent G+C content identify 9702-M4 as a strain of Sinorhizobium meliloti. Sequence analysis of a 16S rDNA fragment gives 9702-M4 a phylogenetic designation most closely related to Sinorhizobium fredii. The extracellular polymer of isolate 9702-M4 is composed of both an extracellular polysaccharide (EPS) and a rough lipopolysaccharide. The EPS component is composed mainly of 4-glucose linkages with monomers of galactose, mannose, and glucuronic acid and has pyruval and acetyl constituents. The lipid fraction and the negative charge associated with carbonyl groups of the exopolymer are thought to account for the binding of polynuclear aromatic hydrocarbons and cationic metals.

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Kiyotani, Tamiko, and Yoko Sugawara. "L-Leucylglycine 0.67-hydrate and [(4S)-2,2-dimethyl-4-(2-methylpropyl)-5-oxoimidazolidin-3-ium-1-yl]acetate." Acta Crystallographica Section C Crystal Structure Communications 68, no. 12 (November 28, 2012): o498—o501. http://dx.doi.org/10.1107/s010827011204810x.

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Crystals of L-leucylglycine (L-Leu–Gly) 0.67-hydrate, C8H16N2O3·0.67H2O, (I), were obtained from an aqueous solution. There are three symmetrically independent dipeptide zwitterionic molecules in (I) and they are parallel to one another. The hydrogen-bond network composed of carboxylate and amino groups and water molecules extends parallel to theabplane. Hydrophilic regions composed of main chains and hydrophobic regions composed of the isobutyl groups of the leucyl residues are aligned alternately along thecaxis. An imidazolidinone derivative was obtained from L-Leu–Gly and acetone,viz.[(4S)-2,2-dimethyl-4-(2-methylpropyl)-5-oxoimidazolidin-3-ium-1-yl]acetate, C11H20N2O3, (II), and was crystallized from a methanol–acetone solution of L-Leu–Gly. The unit-cell parameters coincide with those reported previously for L-Leu–Gly dihydrate revealing that the previously reported values should be assigned to the structure of (II). One of the imidazolidine N atoms is protonated and the ring is nearly planar, except for the protonated N atom. Protonated N atoms and deprotonated carboxy groups of neighbouring molecules form hydrogen-bonded chains. The ring carbonyl group is not involved in hydrogen bonding.

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Lin, X. W., L. M. Chen, and Jing Zhu. "The microstructure of ultrafine carbonyl iron powder." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 4 (August 1990): 252–53. http://dx.doi.org/10.1017/s0424820100174394.

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Carbonyl iron powder has a wide application in the electrical and magnetic industry. In this paper a ultra-fine carbonyl iron powder (UFCIP) of about 20nm in size was examined by CTEM, EELS, HREM and microdiffraction on JEOL—2000FX operating at 200kv. The UFCIP was suspended in ultrasonically agitated alcohol before it was spreaded on a micromesh.Two types of particles exist in that UFCIP as shown in Fig. 1. The larger particles ranging from 50 to 80 nm are zeta—Fe2N, that was identified by microdiffraction. The majority of the UFCIP particles ranging from 5 to 30 nm in diameter were determined to be Fe3O4 and alpha—Fe by the selected area diffraction. At higher magnification it was found that there are two kinds of fine powder in smaller particles: one has a dark core and another one has a bright core. The microdiffractions with a probe of about 6nm in diameter were performed, it indicated that the dark core is the particles of alpha—Fe enclosed in 5nm thick skin of polycrystalline Fe3O4 as shown in Fig. 2 and that the particles with a bright core are composed of polycrystalline gamma—Fe2O3. The HREM images in Fig. 3a and 3b were taken from a same particle but had two orientations with about 10 degree difference related to the incident beam, as the particle was rotated, the bright core remained visible and a round core became an elliptical core.

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Barbosa, Fernanda Gonçalves, Paulo Ricardo Franco Marcelino, Talita Martins Lacerda, Rafael Rodrigues Philippini, Emma Teresa Giancaterino, Marcos Campos Mancebo, Júlio Cesar dos Santos, and Silvio Silvério Da Silva. "Production, Physicochemical and Structural Characterization of a Bioemulsifier Produced in a Culture Medium Composed of Sugarcane Bagasse Hemicellulosic Hydrolysate and Soybean Oil in the Context of Biorefineries." Fermentation 8, no. 11 (November 9, 2022): 618. http://dx.doi.org/10.3390/fermentation8110618.

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Biosurfactants are amphipathic molecules, biodegradable, with reduced toxicity. They can be synthesized by fermentative processes from oleaginous compounds and agro-industrial by-products. In this context, the present study describes the production and the physical, chemical, and structural characterization of the bioemulsifier secreted by the yeast Scheffersomyces shehatae 16-BR6-2AI in a medium containing hemicellulosic sugarcane bagasse hydrolysate combined with soybean oil. The bioemulsifier was produced in Erlenmeyer flasks and isolated; then, the physicochemical and structural characterization of the formed molecule was carried out. The following fermentation parameters were obtained: YX/S = 0.45, YP/S = 0.083, and productivity of 0.076 g/L/h. The bioemulsifier was found to be a polymer containing 53% of carbohydrates, 40.92% of proteins, and 6.08% of lipids, respectively. The FTIR spectrum confirmed the presence of functional groups such as amides, amines, and carbonyls. The bioemulsifier was stable over a range of temperature (−20 °C to 120 °C), salinity (1–15%), and pH (2–12). It was observed that the biomolecule has a better emulsifying action in organic solvents with a non-polar character. Therefore, this biomolecule is a potential substitute for synthetic surfactants and can be used in different applications.

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SHIRAISHI, Noriyuki, Yoko INAI, Wenxiang BI, and Morimitsu NISHIKIMI. "Fragmentation and dimerization of copper-loaded prion protein by copper-catalysed oxidation." Biochemical Journal 387, no. 1 (March 22, 2005): 247–55. http://dx.doi.org/10.1042/bj20041561.

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Prion protein consists of an N-terminal domain containing a series of octapeptide repeats with the consensus sequence PHGGGWGQ and a C-terminal domain composed of three α-helices and two short β-strands. Several studies have shown that the N-terminal domain binds five Cu2+ ions. In the present study, we have investigated copper-catalysed oxidation of a recombinant mouse prion protein, PrP23–231. The copper-loaded PrP23–231 was found to be carbonylated by incubation with dopamine. Besides the formation of carbonyls, a cross-linked species with the dimeric size and C-terminally truncated species were generated. These reactions were retarded in the presence of Cu+- and Cu2+-specific copper chelators, catalase, and SOD (superoxide dismutase), but not in the presence of various bivalent metal ions. Together, these results indicate that the copper bound to prion protein undergoes catalytic cycling in the presence of catecholamines and causes the oxidation of the protein.

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Amaral, Ana Luiza, Jaqueline Pontes Batista, Igor Moraes Mariano, Ludimila Ferreira Gonçalves, Júlia Buiatte Tavares, Adriele Vieira de Souza, Douglas C. Caixeta, et al. "Redox Status of Postmenopausal Women with Single or Multiple Cardiometabolic Diseases Has a Similar Response to Mat Pilates Training." Antioxidants 11, no. 8 (July 26, 2022): 1445. http://dx.doi.org/10.3390/antiox11081445.

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Postmenopausal women have a high prevalence of cardiometabolic diseases and that may associate with higher oxidative stress. Exercise can contribute to the treatment of such diseases, but some modalities, such as Mat Pilates, need to be further studied in terms of their physiological responses. Our aim was to investigate the effects of 12 weeks of Mat Pilates on redox status in postmenopausal women with one or multiple comorbidities of cardiometabolic diseases. Forty-four postmenopausal women were divided into two groups: SINGLE, composed of women with one cardiometabolic disease (n = 20) and MULT, with multimorbidity (n = 24). Mat Pilates training was conducted three times a week for 12 weeks, and each session lasted 50 min. Plasma samples were collected before and after training to analyze the following redox markers: superoxide dismutase, catalase, glutathione peroxidase, total antioxidant capacity due to ferric-reducing antioxidant power (FRAP), reduced glutathione (GSH), uric acid, and carbonyl protein. ANCOVA showed interaction effects in FRAP (p = 0.014). Both groups had reduced levels of catalase (p = 0.240) and GSH (p = 0.309), and increased levels of carbonyl protein (p = 0.053) after intervention. In conclusion, the redox status of postmenopausal women shows no changes mediated by Mat Pilates training between SINGLE and MULT, except for greater reductions of FRAP in SINGLE.

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41

Barbi, Mauricio, Phil R. Bell, Federico Fanti, James J. Dynes, Anezka Kolaceke, Josef Buttigieg, Ian M. Coulson, and Philip J. Currie. "Integumentary structure and composition in an exceptionally well-preserved hadrosaur (Dinosauria: Ornithischia)." PeerJ 7 (October 16, 2019): e7875. http://dx.doi.org/10.7717/peerj.7875.

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Preserved labile tissues (e.g., skin, muscle) in the fossil record of terrestrial vertebrates are increasingly becoming recognized as an important source of biological and taphonomic information. Here, we combine a variety of synchrotron radiation techniques with scanning electron and optical microscopy to elucidate the structure of 72 million-year-old squamous (scaly) skin from a hadrosaurid dinosaur from the Late Cretaceous of Alberta, Canada. Scanning electron and optical microscopy independently reveal that the three-dimensionally preserved scales are associated with a band of carbon-rich layers up to a total thickness of ∼75 microns, which is topographically and morphologically congruent with the stratum corneum in modern reptiles. Compositionally, this band deviates from that of the surrounding sedimentary matrix; Fourier-transform infrared spectroscopy and soft X-ray spectromicroscopy analyses indicate that carbon appears predominantly as carbonyl in the skin. The regions corresponding to the integumentary layers are distinctively enriched in iron compared to the sedimentary matrix and appear with kaolinite-rich laminae. These hosting carbonyl-rich layers are apparently composed of subcircular bodies resembling preserved cell structures. Each of these structures is encapsulated by calcite/vaterite, with iron predominantly concentrated at its center. The presence of iron, calcite/vaterite and kaolinite may, independently or collectively, have played important roles in the preservation of the layered structures.

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Xing, Nan, Feng Tian, Jian Yang, and Yu Kun Li. "Preparation and Basic Characterizations of Alginate-Chitosan Hydrogel." Advanced Materials Research 490-495 (March 2012): 3396–400. http://dx.doi.org/10.4028/www.scientific.net/amr.490-495.3396.

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The aim of this study is to prepare and characterize an alginate-chitosan hydrogel for wound dressing application. The influence of alginate concentrations (1%, 2%, 3% and 4% (w/v)) was investigated. This polyelectrolyte hydrogel is observed to be transparent and flexible. The SEM morphological structure of hydrogel is composed of a dense outer skin layer and a porous cross-section layer. The FTIR and DSC measurements indicated the protonated amino group of chitosan has reacted with the carbonyl group of alginate. Some other properties for the wound dressing application are also reported in other paper. Taken together these results point out that alginate-chitosan polyelectrolyte hydrogel can be considered for wound dressing applications.

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43

Setzer, William N., and William A. Haber. "Leaf Essential Oil Composition of Five Species of Beilschmiedia from Monteverde, Costa Rica." Natural Product Communications 2, no. 1 (January 2007): 1934578X0700200. http://dx.doi.org/10.1177/1934578x0700200116.

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The leaf essential oils of five species of Beilschmiedia from Monteverde, Costa Rica (Beilschmiedia alloiophylla, B. brenesii, B. costaricensis, B. tilaranensis, and an undescribed Beilschmiedia species “chancho blanco”) have been obtained by hydrodistillation and analyzed by GC-MS in order to discern the differences and similarities between the volatile chemical compositions of these species. The principal constituents of B. alloiophylla leaf oil were germacrene D (18.9%), cis- and trans-β-ocimene (18.8% and 9.3%, respectively), α-pinene (11.8%), and bicyclogermacrene (9.1%). The leaf oil of B. brenesii was composed largely of the sesquiterpenes germacrene D (19.3%), β-caryophyllene (13.4%), α-copaene (9.0%), α-humulene (8.1%), and δ-cadinene (5.8%), and the carbonyl compounds 2-undecanone (12.8%), trans-2-hexenal (8.8%), and 2-tridecanone (3.8%). α-Bisabolol (72.1%) dominated the leaf oil of B. costaricensis, while B. tilaranensis had germacrene D (54.9%), β-caryophyllene (14.8%), and δ-cadinene (5.1%) as major components. Beilschmiedia “chancho blanco” leaf oil was composed largely of β-caryophyllene (16.6%), bicyclogermacrene (14.1%), and α-pinene (12.1%).

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Liao, Hsin-Tzu, and Chin-San Wu. "Preparation and characterizations of ternary biodegradable blends composed of polylactide, poly(ε-caprolactone), and wood flour." Journal of Polymer Engineering 32, no. 6-7 (October 1, 2012): 435–44. http://dx.doi.org/10.1515/polyeng-2012-0043.

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Abstract Melt blending of polylactide (PLA), poly(ε-caprolactone) (PCL), and wood flour (WF) was performed in an effort to overcome the major drawbacks (brittleness and high price) of PLA. In addition, the acrylic acid (AA)-grafted PLA70PCL30 (PLA70PCL30-g-AA) was used as the alternative for the preparation of ternary blends to improve the compatibility and the dispersability of WF within the PLA70PCL30 matrix. As expected, PCL improved the elongation at break and the toughness of PLA but decreased the tensile strength and modulus. Because the hydrophilic WF is dispersed physically in the hydrophobic PLA70PCL30 matrix, as the result of Fourier transform infrared analysis, the mechanical properties of PLA70PCL30 became noticeably worse when it was blended with WF. This problem was successfully conquered by using PLA70PCL30-g-AA to replace PLA70PCL30 due to the formation of an ester carbonyl group between PLA70PCL30-g-AA and WF. Furthermore, the PLA70PCL30-g-AA/WF blend provided a plateau tensile strength at break when the WF content was up to 50 wt%. PLA70PCL30/WF exhibited a tensile strength at break of approximately 3–25 MPa more than PLA70PCL30-g-AA/WF. By using p-cresol and tyrosinase, the enzymatic biodegradable test showed that PLA70PCL30-g-AA is somewhat more biodegradable than PLA70PCL30 because the former has better water absorption. After 16 weeks, the weight loss of the PLA70PCL30/WF (50 wt%) composite was >80%. PLA70PCL30-g-AA/WF exhibited a weight loss of approximately 1–12 wt% more than PLA70PCL30-g-AA/WF. It was also found that the addition of WF to PLA70PCL30 or PLA70PCL30-g-AA decreased the crystallinity of PLA and PCL in PLA70PCL30 or PLA70PCL30-g-AA and then increased their biodegradable property.

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45

Kar, Ketaki, Suvam Saha, Rahul Maganbhai Parmar, Arindam Roy, Marie Cordier, Thierry Roisnel, and Sundargopal Ghosh. "Chemistry of CS2 and CS3 Bridged Decaborane Analogues: Regular Coordination Versus Cluster Expansion." Molecules 28, no. 3 (January 19, 2023): 998. http://dx.doi.org/10.3390/molecules28030998.

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In an effort to synthesize metallaheteroborane clusters of higher nuclearity, the reactivity of metallaheteroboranes, nido-[(Cp*M)2B6S2H4(CS3)] (Cp* = C5Me5) (1: M = Co; 2: M = Rh) with various metal carbonyls have been investigated. Photolysis of nido-1 and nido-2 with group 6 metal carbonyls, M’(CO)5.THF (M’ = Mo or W) were performed that led to the formation of a series of adducts [(Cp*M)2B6S2H4(CS3){M’(CO)5}] (3: M = Co, M’ = Mo; 4: M = Co, M’ = W; 5: M = Rh, M’ = Mo; 6: M = Rh, M’ = W) instead of cluster expansion reactions. In these adducts, the S atom of C=S group of di(thioboralane)thione {B2CS3} moiety is coordinated to M’(CO)5 (M = Mo or W) in η1-fashion. On the other hand, thermolysis of nido-1 with Ru3(CO)12 yielded one fused metallaheteroborane cluster [{Ru(CO)3}3S{Ru(CO)}{Ru(CO)2}Co2B6SH4(CH2S2){Ru(CO)3}2S], 7. This 20-vertex-fused cluster is composed of two tetrahedral {Ru3S} and {Ru2B2}, a flat butterfly {Ru3S} and one octadecahedron {Co2RuB7S} core with one missing vertex, coordinated to {Ru2SCH2S2} through two boron and one ruthenium atom. On the other hand, the room temperature reaction of nido-2 with Co2(CO)8 produced one 19-vertex fused metallaheteroborane cluster [(Cp*Rh)2B6H4S4{Co(CO)}2{Co(CO)2}2(μ-CO)S{Co(CO)3}2], 8. Cluster 8 contains one nido-decaborane {Rh2B6S2}, one butterfly {Co2S2} and one bicapped square pyramidal {Co6S} unit that exhibits an intercluster fusion with two sulfur atoms in common. Clusters 3–6 have been characterized by multinuclear NMR and IR spectroscopy, mass spectrometry and structurally determined by XRD analyses. Furthermore, the DFT calculations have been carried out to gain insight into electronic, structural and bonding patterns of the synthesized clusters.

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46

Siqingaowa, Takehiro Tsumuki, Kazuki Ogata, Noriyuki Yonezawa, and Akiko Okamoto. "1-[(Anthracen-9-yl)carbonyl]-2,7-dimethoxynaphthalene: a chain-like structure composed of face-to-face type dimeric molecular aggregates." Acta Crystallographica Section E Crystallographic Communications 72, no. 12 (November 18, 2016): 1819–23. http://dx.doi.org/10.1107/s2056989016018077.

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The asymmetric unit of the title compound, C27H20O3, contains two independent molecules (AandB). The anthracene ring system is connected to the 2,7-dimethoxynaphthalene core in a twisted manner, with dihedral angles of 86.38 (5) and 79.36 (8)°, respectively, for conformersAandB. In the crystal, face-to-face type dimeric molecular aggregates of each conformer are observed. The dimer of conformerAis formed by two pairs of C—H...π interactions, and that of conformerBby a pair of (sp2)C—H...O hydrogen bonds. The dimers of conformerAare linked to each otherviaa π–π stacking interaction between the anthracene rings to form a chain along thebaxis and the chains are aligned along thecaxis, forming a sheet structure. The dimers of conformerBare connected to each otherviaa couple of C—H...π interactions to form a chain along thebaxis. The chains are aligned along thecaxis through (sp2)C—H...O=C hydrogen bonds, forming a sheet parallel to thebcplane. The sheets of conformersAandBare alternately stacked along theaaxisviatwo kinds of intermolecular (sp2)C—H...O=C hydrogen bonds.

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Lim, Jun-Hee, and Sung-Soo Kim. "Multiple magnetic resonance and microwave absorption of metamaterial absorbers composed of double split ring resonators on grounded carbonyl iron composites." AIP Advances 7, no. 12 (December 2017): 125223. http://dx.doi.org/10.1063/1.5013164.

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48

Kawabata, Hiroshi, Yoshitaka Matsui, Ken-ichi Nakayama, Masaaki Yokoyama, and Hiroto Tachikawa. "A Hybrid DFT Study on the Mechanism of the Electron Conductivity of Molecular Devices Composed of Metal and Carbonyl Compounds." Molecular Simulation 30, no. 13-15 (November 15, 2004): 923–28. http://dx.doi.org/10.1080/08927020412331298676.

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49

Norouzi, Omid, Mohammad Heidari, Mario M. Martinez, and Animesh Dutta. "New Insights for the Future Design of Composites Composed of Hydrochar and Zeolite for Developing Advanced Biofuels from Cranberry Pomace." Energies 13, no. 24 (December 14, 2020): 6600. http://dx.doi.org/10.3390/en13246600.

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This study provides fundamental insight and offers a promising catalytic hydrothermal method to harness cranberry pomace as a potential bioenergy and/or hydrochar source. The physical and chemical properties of Canadian cranberry pomace, supplied by Fruit d’Or Inc., were examined and the optimum operational conditions, in terms of biocrude yield, were obtained by the I-optimal matrix of Design Expert 11. Afterward, cranberry pomace hydrochar (CPH) and zeolite were separately introduced to the hydrothermal liquefaction (HTL) process to investigate the benefits and disadvantages associated with their catalytic activity. CPH was found to be a better host than zeolite to accommodate cellulosic sugars and showed great catalytic performance in producing hydrocarbons. However, high amounts of corrosive amino and aliphatic acids hinder the practical application of CPH as a catalyst. Alternatively, zeolite, as a commercial high surface area catalyst, had a higher activity for deoxygenation of compounds containing carbonyl, carboxyl, and hydroxyl groups than CPH and resulted in higher selectivity of phenols. Due to the low hydrothermal structural stability, coke formation, and narrow pore size distribution, further activations and modifications are needed to improve the catalytic behavior of zeolite. Our results suggest that a composite composed of CPH and zeolite can resolve the abovementioned limitations and help with the development and commercialization of advanced biofuels from cranberry pomace.

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Münch, G., B. Kuhla, H. J. Lüth, T. Arendt, and S. R. Robinson. "Anti-AGEing defences against Alzheimer's disease." Biochemical Society Transactions 31, no. 6 (December 1, 2003): 1397–99. http://dx.doi.org/10.1042/bst0311397.

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Accumulation of insoluble protein deposits and their cross-linking by AGEs (advanced glycation end products) in the brain is a feature of aging and neurodegeneration, especially in AD (Alzheimer's disease). In AD, two types of fibrillar protein aggregates are present: extracellular deposits (plaques) consisting mainly of Aβ (β-amyloid peptide), and intracellular deposits (tangles) composed predominantly of microtubule-associated protein tau. Both plaques and tangles are modified by AGEs, which occurs particularly at lysine and arginine residues. Interaction of a synthetic amyloid plaque (fibrillar Aβ) with microglia leads to a strong pro-inflammatory response, indicating that priming of immune cells with β-amyloid potentiates their response to secondary stimuli such as AGE and cytokines such as interferon-γ. Formation of hyperphosphorylated and cross-linked microtubule-associated protein tau aggregates, especially tau dimers as the first step in tangle formation, can be induced in vitro by the combination of okadaic acid, a PP2A phosphatase inhibitor, and methylglyoxal. These results suggest that excess production of reactive carbonyl compound (‘carbonyl stress’) and subsequent AGE formation can contribute to cross-linking of protein fibrils and to pathological pro-inflammatory signalling, which all contribute to pathological changes and dementia progression in AD. However, the human brain has developed the glyoxalase system, a most effective defence system to scavenge small dicarbonyl compounds such as glyoxal and methylglyoxal. Very importantly, this system needs GSH as a rate-limiting cofactor. Since GSH is limited under conditions of oxidative stress and inflammation, supplementation with antioxidants such as lipoic acid, vitamin E or flavonoids could indirectly strengthen the anti-glycation defence system in AD. In addition, synthetic carbonyl scavengers and anti-inflammatory drugs could also be valuable drugs for the ‘anti-glycation’ treatment of AD.

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