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991.
Samuel B. Dulay Sandra Julich Herbert Tomaso Ciara K. O’Sullivan 《Analytical and bioanalytical chemistry》2014,406(19):4685-4690
Tularemia, also known as rabbit fever, is a highly infectious zoonotic disease caused by a non-motile and non-spore-forming Gram-negative coccoid rod bacterium, Francisella tularensis. It occurs naturally in lagomorphs (rabbits and hares), but many animals have been reported to be susceptible. Transmission to humans is mostly caused by inhalation of aerosolised bacteria, handling of infected animals, arthropod stings, and ingestion of contaminated foods and water. At present, pathogenic isolation, molecular detection, and serology are the most commonly used methods to confirm the diagnosis of tularemia. In this work, an electrochemical immunosensor for the detection of anti-F. tularensis antibodies was developed, consisting of gold-based self-assembled monolayers of a carboxylic-group-terminated bipodal alkanethiol that is covalently linked to a lipopolysaccharide (LPS) that can be found in the outer membrane of the bacteria F. tularensis. The presence of anti-F. tularensis antibodies was measured using horseradish peroxidase-labelled protein A (HRP-protein A) from Staphylococcus aureus, and the developed immunosensor gave a stable quantitative response to different anti-F. tularensis FB11 antibody concentrations after 30 min with a limit of detection of 15 ng/mL, RSD of 9 %, n?=?3. The developed immunosensor was tested with serum from animals infected with tularemia and was compared to the results obtained using ELISA showing an excellent degree of correlation. 相似文献
992.
Sandra Simon Pierre Alcouffe Eliane Espuche 《Journal of Polymer Science.Polymer Physics》2014,52(18):1211-1220
In this study, bimetallic/polymer films are synthesized from polyetherimide (PEI), palladium acetate and silver nitrate for a wide range of total metal amount (from 0 to 30 wt %) and different Ag to Pd molar ratios. Hybrid precursor films are first prepared from polymer/metal complex solutions and the metal nanoparticles are then generated within the PEI matrix by annealing the precursor film under specific conditions. Reference neat PEI films and monometallic films are prepared in the same conditions. Interestingly, formation of AgPd alloys directly within the polymer films is for the first time obtained from a very simple and environmentally friendly route. Based on X‐ray diffraction and transmission electron microscopy analyses, a nanostructuration mechanism is proposed. The interactions of hydrogen towards the nanocomposites are investigated and discussed as a function of the nanoparticle composition. The impact of the nanostructuration is also studied on H2, CO2, and He permeation properties. Significant improvement of barrier properties is achieved. The pertinent parameters of the gas transport are identified and modelled for each gas/composite system. Finally, from both morphological and gas transport analyses, it is concluded that in situ generation AgPd alloys with Pd to Ag ratio above 1 leads to very interesting and promising materials. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1211–1220 相似文献
993.
994.
Polymer‐Derived Silicoboron Carbonitride Foams for CO2 Capture: From Design to Application as Scaffolds for the in Situ Growth of Metal–Organic Frameworks 下载免费PDF全文
Dr. Fabien Sandra Dr. Martin Depardieu Dr. Zineb Mouline Prof. Gérard L. Vignoles Prof. Yuji Iwamoto Prof. Philippe Miele Prof. Rénal Backov Dr. Samuel Bernard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8346-8357
A template‐assisted polymer‐derived ceramic route is investigated for preparing a series of silicoboron carbonitride (Si/B/C/N) foams with a hierarchical pore size distribution and tailorable interconnected porosity. A boron‐modified polycarbosilazane was selected to impregnate monolithic silica and carbonaceous templates and form after pyrolysis and template removal Si/B/C/N foams. By changing the hard template nature and controlling the quantity of polymer to be impregnated, controlled micropore/macropore distributions with mesoscopic cell windows are generated. Specific surface areas from 29 to 239 m2 g?1 and porosities from 51 to 77 % are achieved. These foams combine a low density with a thermal insulation and a relatively good thermostructural stability. Their particular structure allowed the in situ growth of metal–organic frameworks (MOFs) directly within the open‐cell structure. MOFs offered a microporosity feature to the resulting Si/B/C/N@MOF composite foams that allowed increasing the specific surface area to provide CO2 uptake of 2.2 %. 相似文献
995.
996.
Tris(3,5‐dimethylpyrazolyl)methane‐Based Heterobimetallic Complexes that Contain Zn and CdTransition‐Metal Bonds: Synthesis,Structures, and Quantum Chemical Calculations 下载免费PDF全文
Dr. Jens Meyer Dr. Sandra González‐Gallardo Silvia Hohnstein Delphine Garnier Dr. Markus K. Armbruster Dr. Karin Fink Prof. Dr. Wim Klopper Prof. Dr. Frank Breher 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2905-2914
Reactions of the tris(3,5‐dimethylpyrazolyl)methanide amido complexes [M′{C(3,5‐Me2pz)3}{N(SiMe3)2}] (M′=Mg ( 1 a ), Zn ( 1 b ), Cd ( 1 c ); 3,5‐Me2pz=3,5‐dimethylpyrazolyl) with two equivalents of the acidic Group 6 cyclopentadienyl (Cp) tricarbonyl hydrides [MCp(CO)3H] (M=Cr ( 2 a ), Mo ( 2 b )) gave different types of heterobimetallic complex. In each case, two reactions took place, namely the conversion of the tris(3,5‐dimethylpyrazolyl)methanide ligand (Tpmd*) into the ‐methane derivative (Tpm*) and the reaction of the acidic hydride M?H bond with the M′?N(SiMe3)2 moiety. The latter produces HN(SiMe3)2 as a byproduct. The Group 2 representatives [Mg(Tpm*){MCp(CO)3}2(thf)] ( 3 a / b ) form isocarbonyl bridges between the magnesium and chromium/molybdenum centres, whereas direct metal–metal bonds are formed in the case of the ions [Zn(Tpm*){MCp(CO)3}]+ ( 4 a / b ; [MCp(CO)3]? as the counteranion) and [Cd(Tpm*){MCp(CO)3}(thf)]+ ( 5 a / b ; [Cd{MCp(CO)3}3]? as the counteranion). Complexes 4 a and 5 a / b are the first complexes that contain Zn?Cr, Cd?Cr, and Cd?Mo bonds (bond lengths 251.6, 269.8, and 278.9 pm, respectively). Quantum chemical calculations on 4 a / b* (and also on 5 a / b* ) provide evidence for an interaction between the metal atoms. 相似文献
997.
998.
Paul A. Gurr Joel M. P. Scofield Jinguk Kim Qiang Fu Sandra E. Kentish Greg G. Qiao 《Journal of polymer science. Part A, Polymer chemistry》2014,52(23):3372-3382
This article demonstrates the successful fabrication of thin‐film‐composite (TFC) membranes containing well‐defined soft‐hard‐soft triblock copolymers. Based on “hard” polyimide (PI) and “soft” polydimethylsiloxane (PDMS), these triblock copolymers (PDMS‐b‐PI‐b‐PDMS), were prepared via condensation polymerization, and end‐group allylic functionalization to prepare the polyimide component and subsequent “click” coupling with the soft azido functionalized PDMS component. The selective layer consisted of pure PDMS‐b‐PI‐b‐PDMS copolymers which were cast onto a precast crosslinked‐PDMS gutter layer which in turn was cast onto a porous polyacrylonitrile coated substrate. The TFC membranes' gas transport properties, primarily for the separation of carbon dioxide (CO2) from nitrogen (N2), were determined at 35 °C and at a feed pressure of 2 atm. The TFC membranes showed improvements in gas permselectivity with increasing PDMS weight fraction. These results demonstrate the ability for glassy, hard polymer components to be coated onto otherwise incompatible surfaces of highly permeable soft TFC substrates through covalent coupling. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3372–3382 相似文献
999.
Alan S. Cigoli Sandra Mantovani Giuseppe Metere 《Applied Categorical Structures》2014,22(5-6):931-960
In a semi-abelian category, we give a categorical construction of the push forward of an internal pre-crossed module, generalizing the pushout of a short exact sequence in abelian categories. The main properties of the push forward are discussed. A simplified version is given for action accessible categories, providing examples in the categories of rings and Lie algebras. We show that push forwards can be used to obtain the crossed module version of the comprehensive factorization for internal groupoids. 相似文献
1000.
Hydrocarbon solubility,permeability, and competitive sorption effects in polymer of intrinsic microporosity (PIM‐1) membranes 下载免费PDF全文
Colin A. Scholes Jianyong Jin Geoff W. Stevens Sandra E. Kentish 《Journal of Polymer Science.Polymer Physics》2016,54(3):397-404
The sorption and permeation of pentane, hexane, and toluene through highly permeable polymer of intrinsic microporosity (PIM‐1) membranes were investigated. It was established that the hydrocarbons sorbed strongly within the micro‐void regions of the PIM‐1 membrane. The sorption concentration was similar for the paraffins, pentane and hexane, but greater for aromatic toluene at high vapor activities. The magnitude of the hydrocarbon permeability was associated with the critical temperature of the hydrocarbon. The PIM‐1 membrane displayed selectivity for the three hydrocarbons over CO2. As a consequence, the presence of the three hydrocarbons dramatically reduced the permeability of CO2 and N2 under mixed gas–vapor conditions to 68%–95% below the dry gas value. For all three hydrocarbons the N2 permeability was more strongly impacted than CO2 permeability, and hence the ideal CO2/N2 selectivity of PIM‐1 increased. It was determined that CO2 and N2 solubility decreased because of hydrocarbon competitive sorption while CO2 and N2 diffusivity also decreased because of anti‐plasticization, which was due to the presence of hydrocarbon clusters within the membrane structure. There was a clear correlation between the magnitude of anti‐plasticization and the critical temperature of the hydrocarbon. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 397–404 相似文献