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91.
Walter Navarrini Tommaso Brivio Dmitrij Capobianco Maria Vittoria Diamanti Mariapia Pedeferri Luca Magagnin Giuseppe Resnati 《Journal of Coatings Technology and Research》2011,8(2):153-160
In this study amorphous fluorinated coatings applied to anodized titanium surface have been investigated. A copolymer between
tetrafluoroethylene and perfluoro-4-trifluoromethoxy-1,3-dioxole (AD60) and two perfluoropolyether containing ammonium phosphate
(F10) or triethoxysilane (S10) functionalities have been tested. To estimate the color alteration of the anodized titanium
surfaces due to the application of the coatings, spectrophotometric analyses have been made. Water and n-dodecane contact angles as well as apparent surface energy have been evaluated. Ellipsometry and atomic force microscopy
data have been used to measure the thickness of the fluorinated coatings. A tailored mechanical preliminary test has also
been explored to evaluate the adhesion of the coatings on the anodized titanium surface. The resistance to surface soiling
with castor oil was also preliminarily investigated. The fluorinated coating tested on anodized titanium showed a low apparent
surface energy and high chromatic aspect conservation, this is particularly evident for the titanium anodized coated with
triethoxysilane functionalities fluoropolymers S10. 相似文献
92.
93.
Simone Albertazzi Francesco Basile Davide Barbera Patricia Benito Jan Brandin Jessica Einvall Giuseppe Fornasari Ferruccio Trifir�� Angelo Vaccari 《Topics in Catalysis》2011,54(10-12):746-754
The deactivation of a nickel reforming catalyst during the upgrading of the producer gas obtained by gasification of lignocellulosic biomass was studied. The research involved several steps: the selective deactivation of the catalyst in a laboratory scale; the streaming of the catalyst with the producer gas of a downdraft and an oxygen/steam circulating fluidized bed (CFB) gasifier; and tests in a reformer placed in a slipstream of the CFB gasifier. The information obtained allowed to elucidate the catalyst deactivation mechanisms taking place during the reforming of the producer gas: physical deactivation by deposition of fine ashes, aerosol particulate or carbon; poisoning by H2S and HCl present in the gas phase and thermal sintering because of the high operation temperatures required to avoid the chemical deactivation. These physical and chemical effects depended on the composition of the biomass fuel. 相似文献
94.
Flaender M Sicoli G Aci-Seche S Reignier T Maurel V Saint-Pierre C Boulard Y Gambarelli S Gasparutto D 《Chembiochem : a European journal of chemical biology》2011,12(17):2560-2563
In a spin: Spin-labeled oligonucleotides produced by click chemistry can be studied by EPR, by using a DEER sequence. This was used to test a complex triple-labeling strategy with damaged DNA. Extensive and accurate analysis of DNA structure and enzymatic repair processes were performed after digestion by EndoIV. Modified DNA structures and DNA-protein interactions can now be readily studied. 相似文献
95.
Molecularly imprinted polymers: present and future prospective 总被引:2,自引:0,他引:2
Vasapollo G Sole RD Mergola L Lazzoi MR Scardino A Scorrano S Mele G 《International journal of molecular sciences》2011,12(9):5908-5945
Molecular Imprinting Technology (MIT) is a technique to design artificial receptors with a predetermined selectivity and specificity for a given analyte, which can be used as ideal materials in various application fields. Molecularly Imprinted Polymers (MIPs), the polymeric matrices obtained using the imprinting technology, are robust molecular recognition elements able to mimic natural recognition entities, such as antibodies and biological receptors, useful to separate and analyze complicated samples such as biological fluids and environmental samples. The scope of this review is to provide a general overview on MIPs field discussing first general aspects in MIP preparation and then dealing with various application aspects. This review aims to outline the molecularly imprinted process and present a summary of principal application fields of molecularly imprinted polymers, focusing on chemical sensing, separation science, drug delivery and catalysis. Some significant aspects about preparation and application of the molecular imprinting polymers with examples taken from the recent literature will be discussed. Theoretical and experimental parameters for MIPs design in terms of the interaction between template and polymer functionalities will be considered and synthesis methods for the improvement of MIP recognition properties will also be presented. 相似文献
96.
Cozza G Gianoncelli A Bonvini P Zorzi E Pasquale R Rosolen A Pinna LA Meggio F Zagotto G Moro S 《ChemMedChem》2011,6(12):2273-2286
Casein kinase 2 (CK2) is a ubiquitous, essential, and highly pleiotropic protein kinase; its abnormally high constitutive activity is suspected to underlie its pathogenic potential in neoplasia and other relevant diseases. Previously, using different in silico screening approaches, two potent and selective CK2 inhibitors were identified by our group: ellagic acid, a naturally occurring tannic acid derivative (K(i)=20 nM) and 3,8-dibromo-7-hydroxy-4-methylchromen-2-one (DBC, K(i)=60 nM). Comparing the crystallographic binding modes of both ellagic acid and DBC, an X-ray structure-driven merging approach was taken to design novel CK2 inhibitors with improved target affinity. A urolithin moiety is proposed as a possible bridging scaffold between the two known CK2 inhibitors, ellagic acid and DBC. Optimization of urolithin A as the bridging moiety led to the identification of 4-bromo-3,8-dihydroxy-benzo[c]chromen-6-one as a novel, potent and selective CK2 inhibitor, which shows a K(i) value of 7 nM against the protein kinase, representing a significant improvement in affinity for the target compared with the two parent fragments. 相似文献
97.
Giuseppe Olivieri Antonio Marzocchella Roberto Andreozzi Gabriele Pinto Antonino Pollio 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(6):776-783
BACKGROUND: This paper reports the results of an experimental campaign of autotrophic cultures of Stichococcus strains aiming at selecting the most promising strain for biofuel production. The strain selected—S. bacillaris 158/11—was cultivated in 1 L lab‐scale bubble column photobioreactors under fed‐batch and semi‐continuous conditions. A Bold basal medium supplemented with NaNO3 as nitrogen source was adopted. Tests were carried out at 23 °C, 140 µE m?2 s?1, and air flow rate ranging between 0.4 and 4 vvm. Cultures were characterized in terms of pH, concentration of total nitrogen, total organic carbon, total inorganic carbon, biomass, lipid fraction and methyl‐ester distribution of transesterified lipids. RESULTS: S. bacillaris 158/11 proved to be the best strain to produce biodiesel. Methyl‐ester distribution was characterized by a large fraction of methyl palmitate, methyl linolenate, methyl linoleate, and methyl oleate along with phytol. The process photosynthetic efficiency—fraction of available light stored as chemical energy ‐ was about 1.5%. Specific biomass productivity was ~60 mgDM L?1 day?1 under the semi‐continuous conditions tested. Total lipid productivity was 14 mg L?1 day?1 at a dilution rate of 0.050 L day?1. CONCLUSION: S. bacillaris 158/11 is a potential strain for massive microalgae cultures for biofuel production. Higher biomass/total‐lipid productivity could be obtained in sunlight. Copyright © 2011 Society of Chemical Industry 相似文献
98.
Claudio Colleoni Maria Rosaria Massafra Veronica Migani Giuseppe Rosace 《应用聚合物科学杂志》2011,120(4):2122-2129
Textile finishing includes all processes that help to maintain the value or increase the value of the textile material. It encompasses dyeing, printing, and all the finishing treatments to realize durable press, soil release, flame retardant, antistatic, antimicrobial, or water/oil repellency properties. When these properties are realized on dyed textile fabric, one effect could be ascribed to the color change induced by finishing operations. This research focuses on the assessment of color alterations occurring on the dyed cotton/polyester blended fabrics due to the nanoparticle‐sized dendrimer (DWR), dendrimer–fluorocarbon (DWOR), and fluorocarbon (FWOR) finishing onto their surfaces. The dependence of color on the surface state of treated textiles is calculated in the context of spectrophotometric measurements. Modification of the surface roughness by reflectance spectrum and the absorbance of finishes in visible range were investigated to determine color changes between the original (control fabric, dyed but not treated) and treated fabrics. As a result of color matching calculated by CIE‐Lab values, color change is related to the surface roughness associated with absorbance values of applied finishes. In addition, fabrics mechanical properties were evaluated to estimate if finishing agents application gives rise to other changes, besides color alterations. The fabrics mechanical properties have been found not significantly altered by the aforementioned finishing treatments. These results could be applied for industrial needs (quality control), or in the artistic field of conservation, or restoration (to follow the color of paintings). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
99.
Daniel Whittaker Andreas Geist Giuseppe Modolo Robin Taylor Mark Sarsfield Andreas Wilden 《溶剂提取与离子交换》2018,36(3):223-256
Over the last decade there has been much interest in the applications of diglycolamide (DGA) ligands for the extraction of the trivalent lanthanide and actinide ions from PUREX high active raffinates or dissolved spent nuclear fuel. Of the DGAs, the N,N,N’,N’-tetraoctyldiglycolamide (TODGA) is the best known and most widely studied. A number of new actinide separation processes have been proposed based on extraction with TODGA. This review covers TODGA-based processes and extraction data, specifically focusing on how phase modifiers have been used to increase metal loading and thus enhance the operating process envelopes. Effects of third phase formation and the organic phase speciation are reviewed in this context. Relevant aspects of the extraction chemistry of important solvents (TODGA-modifier-diluent combinations) are described and their performances demonstrated by a consideration of the published flowsheet tests. It is seen that modifiers are successfully enabling the use of TODGA in actinide separation processes but to date the identification and testing of suitable modifiers has been rather empirical. There is a growing understanding of the fundamental chemistry occurring in the organic phase and how that affects extractant speciation and metal loading capacity but studies are still needed if TODGA-based flowsheets are to become an industrially deployable option for minor actinide (MA) recovery processes. 相似文献
100.
Sara Duce Fabio Pesciaioli Lucia Gramigna Luca Bernardi Andrea Mazzanti Alfredo Ricci Giuseppe Bartoli Giorgio Bencivenni 《Advanced Synthesis \u0026amp; Catalysis》2011,353(6):860-864
The first catalytic asymmetric Pictet–Spengler reaction of isatins is presented. BINOL‐derived phosphoric acids were found to be competent catalysts for this transformation, giving challenging spirooxindole structures bearing a quaternary stereocentre with generally good results. The 1,2,3,4‐tetrahydro‐β‐carboline products (spiroindolinones) are the core of some newly discovered anti‐malarial agents. 相似文献