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71.
Gibb AR Suckling DM El-Sayed AM Bohman B Unelius CR Dymock JJ Larsen ML Willoughby BE 《Journal of chemical ecology》2007,33(4):839-847
The grass webworm Herpetogramma licarsisalis (Lepidoptera: Crambidae), which has recently established in pasture in Northland, New Zealand, is an important pest of many
tropical and subtropical grasses. Two pheromone components, (Z)-11-hexadecen-1-yl acetate (Z11–16:Ac) and (11Z,13E)-hexadecadien-1-yl acetate (Z11,E13–16:Ac), were identified in pheromone gland extracts of female moths by gas chromatography (GC), GC-electroantennographic
detection, and GC-mass spectrometry in conjunction with microchemical tests (dimethyldisulfide and 4-methyl-1,2,4-triazoline-3,5-dione
derivatizations). Z11,E13–16:Ac and its geometric isomer (11E,13Z)-hexadecadien-1-yl acetate (E11,Z13–16:Ac) were synthesized via stereoselective Wittig reactions, and the identity of the diene present in the pheromone glands
was confirmed to be Z11,E13–16:Ac. Field bioassays at Indooroopilly in Brisbane, Australia, established that Z11,E13–16:Ac was necessary and sufficient for attraction of male grass webworm moths and that the corresponding alcohol, (11Z,13E)-hexadecadien-1-ol (Z11,E13–16:OH), had a strong inhibitory effect on trap catches at the ratios tested. When mixed with Z11,E13–16:Ac in various ratios, Z11–16:Ac had no effect on the attractiveness of lures.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
72.
Zhiyi Ding Feifei Du Richard Garland Averitt V Gabriel Jakobsson Carl-Fredrik Rnnow Milladur Rahman Alexandru Schiopu Henrik Thorlacius 《International journal of molecular sciences》2021,22(23)
S100A9, a pro-inflammatory alarmin, is up-regulated in inflamed tissues. However, the role of S100A9 in regulating neutrophil activation, inflammation and lung damage in sepsis is not known. Herein, we hypothesized that blocking S100A9 function may attenuate neutrophil recruitment in septic lung injury. Male C57BL/6 mice were pretreated with the S100A9 inhibitor ABR-238901 (10 mg/kg), prior to cercal ligation and puncture (CLP). Bronchoalveolar lavage fluid (BALF) and lung tissue were harvested for analysis of neutrophil infiltration as well as edema and CXC chemokine production. Blood was collected for analysis of membrane-activated complex-1 (Mac-1) expression on neutrophils as well as CXC chemokines and IL-6 in plasma. Induction of CLP markedly increased plasma levels of S100A9. ABR-238901 decreased CLP-induced neutrophil infiltration and edema formation in the lung. In addition, inhibition of S100A9 decreased the CLP-induced up-regulation of Mac-1 on neutrophils. Administration of ABR-238901 also inhibited the CLP-induced increase of CXCL-1, CXCL-2 and IL-6 in plasma and lungs. Our results suggest that S100A9 promotes neutrophil activation and pulmonary accumulation in sepsis. Targeting S100A9 function decreased formation of CXC chemokines in circulation and lungs and attenuated sepsis-induced lung damage. These novel findings suggest that S100A9 plays an important pro-inflammatory role in sepsis and could be a useful target to protect against the excessive inflammation and lung damage associated with the disease. 相似文献
73.
Designing oligomeric ethylene terephtalate building blocks by chemical recycling of polyethylene terephtalate 下载免费PDF全文
The intelligent recycling of plastics waste is a major concern. Because of the widespread use of polyethylene terephtalate, considerable amounts of PET waste are generated that are ideally re‐introduced into the material cycle by generating second generation products without loss of materials performance. Chemical recycling methods are often expensive and entail environmentally hazardous by‐products. Established mechanical methods generally provide materials of reduced quality, leading to products of lower quality. These drawbacks can be avoided by the development of new recycling methods that provide materials of high quality in every step of the production cycle. In the present work, oligomeric ethylene terephthalate with defined degrees of polymerization and defined molecular weight is produced by melt‐mixing PET with different quantities of adipic acid as an alternative pathway of recycling PET with respect to conventional methods, offering ecofriendly and economical aspects. Additionally, block‐copolyesters of defined block length are designed from the oligomeric products. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39786. 相似文献
74.
75.
Combination of Reaction and Separation in Heterogeneous Catalytic Hydrogenation of Ethylformate 下载免费PDF全文
Gerson Martin Carla Pereira Frank Pettersson Henrik Saxén Dmitry Y. Murzin Alírio Rodrigues Tapio Salmi 《化学工程与技术》2015,38(5):804-812
Continuous hydrogenation reaction of ethyl benzoylformate was studied over a (–)‐cinchonidine (CD)‐modified Pt/Al2O3 catalyst. The catalyst showed a good stability, and high enantioselectivity was achieved in the fixed‐bed reactor. Chromatographic separation of (R)‐ and (S)‐ethyl mandelate originating from a post‐continuous hydrogenation reaction of ethyl benzoylformate over the (–)‐CD‐modified Pt/Al2O3 catalyst was investigated in the same reaction mixture. A commercial column filled with a chiral selector resin was chosen as a perspective preparative‐scale adsorbent. Since adsorption equilibrium isotherms were linear within the entire investigated range of concentrations, they were determined by pulse experiments for the isomers present in a post‐reaction mixture. Breakthrough curves were measured and described successfully by the dispersive plug‐flow model with linear driving force approximation. 相似文献
76.
77.
Helga Gunnlaugsdottir Björn Sivik 《Journal of the American Oil Chemists' Society》1997,74(11):1483-1490
A combined process of lipase (E.C. 3.1.1.3) catalysis and extraction of product with supercritical carbon dioxide was studied.
The effect of different flow rates of the extraction fluid on the selective removal of the ethyl esters (EE) synthesized in
a lipase-catalyzed alcoholysis of cod liver oil with ethanol was investigated. The faster the flow rate, the faster the extraction
rate and the higher the recovery of EE. For example, after a 270-min extraction, the total recovery of EE was 1520 mg for
a flow rate of 0.3 liter carbon dioxide at atmospheric pressure and room temperature/min (NL/min) as compared to 250 mg when
0.015 NL/min was used. The concentration of EE in the carbon dioxide was found to decrease with increasing flow rate, which
indicates that the rate of diffusion of EE limits their extraction at fast flow rates. A high flow rate was found to result
in a more selective extraction of EE, i.e., less amounts of other lipid components present in the reaction mixture were coextracted
with the EE. Further, by increasing the flow rate, the equilibrium of the reaction was shifted slightly toward ester synthesis.
An increase in the flow rate from 0.015 to 0.075 NL/min resulted in an approximately 10% increase in total conversion (from
73 to 82%), whereas only a negligible increase was obtained when the flow rate was increased further to 0.15 NL/min. 相似文献
78.
A new flame retardant based on an ammonium phosphonate is studied with respect to its thermal decomposition and its mode of action in wood‐plastic composites (WPCs). The measurements are carried out by means of fire tests (cone calorimeter) and pyrolysis investigations (thermogravimetry, infrared spectroscopy). The flame retardant acts mainly in the condensed phase by increasing the amount of residue formed by the wood part in the WPC. Additional flame dilution is achieved by the release of water, ammonia and carbon dioxide during the decomposition of the flame retardant.
79.
80.
Björn Sten Mark Kretzschmar Paul Bergelt Daniel Göhler Fabian Firmbach Ronny Köcher Andreas Heft 《Aerosol science and technology》2020,54(10):1124-1134
Abstract For the purpose of silica surface layer modulation, a pneumatic-controlled two-substance atomizer with inertia-based coarse droplet separation was operated at different system pressures for tetraethyl orthosilicate precursor aerosol supply during combustion chemical vapor deposition. A comprehensive testing study was performed to characterize the atomizer’s performance characteristics, initial precursor aerosols at the atomizer’s outlet, transformed aerosols before combustion, combustion aerosols and formed layers. Laser diffraction spectrometry, differential electrical mobility analyses and condensation particle counting were used for aerosol characterization with regard to particle size and particle production quantities. Layers were characterized by scanning electron microscopy, atomic force microscopy, spectral ellipsometry, water contact angle measurements and light transmission concerning geometric properties (thickness, surface structure and roughness) and physical behaviors (i.e., optical behaviors, hydrophobicity). Results show a quasi-linear relationship of the ejection mass flow of the pneumatic-controlled atomizer and geometric layer properties which again show a direct relationship to the physical properties. No correlation was found between the aerosols before combustion and the combustion aerosols since the majority of combustion aerosol particles are synthesized solely from the gas phase based on evaporated precursor material. Copyright © 2020 American Association for Aerosol Research 相似文献