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排序方式: 共有390条查询结果,搜索用时 15 毫秒
61.
Influence of vineyard altitude on Glera grape ripening (Vitis vinifera L.): effects on aroma evolution and wine sensory profile 下载免费PDF全文
62.
Giuseppe Di Franco Livan Fratini Antonino Pasta Vincenzo F. Ruisi 《International Journal of Material Forming》2013,6(1):137-144
In the present paper the possibility to join aluminium alloys blanks and carbon fibre composites panels by self-piercing riveting operation is considered. In particular a few case studies were carried out at the varying of the process parameters. The effectiveness of the obtained joints was tested through tensile tests and through fatigue ones; what is more the process mechanics was highlighted through proper macro and micro observations of the transverse sections of the joints. The failure mechanics of the obtained joints were also considered in order to highlight the mechanisms which occur and determine the lost of the load carrying capability of the joints. Finally a numerical model of the process was carried out and the residual stress state after piercing was highlighted. The developed experiments and simulations demonstrated that self-piercing riveting can be effectively used to join carbon fiber composite panels and aluminum blanks. 相似文献
63.
Jose R. Cabrero‐Antonino Antonio Leyva‐Prez Avelino Corma 《Advanced Synthesis \u0026amp; Catalysis》2012,354(4):678-687
The bis(triflimide)iron(III) salt catalyzes the hydrothiolation of styrenes in a Markovnikov fashion with good selectivities and high yields. After isolation, different benzylic thioethers are obtained. This iron(III) catalyst is unique in terms of regioselectivity and represents a sustainable and economic alternative to those processes based on stoichiometric reagents. 相似文献
64.
Negro D Montesano V Grieco S Crupi P Sarli G De Lisi A Sonnante G 《Journal of food science》2012,77(2):C244-C252
Polyphenol compounds, particularly caffeoylquinic acids and flavonoids, were measured in different tissues and developmental stages of 6 artichoke varietal types diffused in the Mediterranean region. Flower heads were subdivided into external, intermediate, internal bracts, and receptacle, while leaves were collected at the vegetative and productive stages. The main polyphenols detected were chlorogenic acid, cynarin, luteolin 7-O-rutinoside, and luteolin 7-O-glucoside. "Violet de Provence" artichoke proved to retain the highest content of total phenols. Single polyphenols accumulated preferentially in specific parts of capitula. In leaves, most polyphenols were detected in the productive stage of the plant. Altogether, results provide useful indications for the promotion of artichoke as nutraceutical food and for the extraction of health-promoting substances in particular tissues/stages of the artichoke plant. PRACTICAL APPLICATION: We describe the content of phenolic compounds in various artichoke tissues, developmental stages, and varieties. Results indicate that artichoke leaves represent an important source of these health-promoting compounds, also useful for phytopharmaceutical applications. A wider utilization of specific artichoke types should be strongly encouraged not only as a food for the fresh market, as they are now used, but also for the pharmaceutical industry, since the content of phenolic compounds is abundant both in the heads and in the leaves. 相似文献
65.
Bo Yang Jianguo Tang Peihua Yang Yao Wang Jixian Liu Haiyan Liu Rui Wang Zhen Huang Jingquan Liu Laurence A. Belfiore 《应用聚合物科学杂志》2012,126(2):706-712
In this article, a copper‐in‐polymer‐gradient composite film (CPGCF) was synthesized by electrochemical strategy via reducing a solvent‐swollen cathode film (SCF). The latex nanoparticles of a ternary copolymer including styrene, butyl acrylate, and acrylic acid structural units play the key role to form well‐graded copper distribution in this ternary copolymer matrix through the porous morphological structure developed by latex nanoparticle semimelt joining. The morphological structure along cross‐section of CPGCF includes three layers: (1) a dense copper layer in ternary copolymer matrix whose most outside was originally attached to cathode in electrochemical reactor, (2) a shrublike layer that grew from dense copper layer, and (3) a clear layer in which there is no obvious reduced copper phase whose most outside was originally contacted with liquid electrolyte medium in electrochemical reactor. As experimental aspects, the influences of emulsion polymerization conditions of ternary copolymer, predrying time and temperature of SCF, dc voltage in electrochemical reduction on CPGCF structure were investigated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
66.
Paloma Oliveira Antonino Assis de Carvalho Gerlane Coelho Bernardo Guerra Graciele da Silva Campelo Borges Fabrícia França Bezerril Karoliny Brito Sampaio Thaís Santana Ribeiro Maria Teresa Bertoldo Pacheco Raquel Fernanda Milani Rosana Goldbeck Patrícia Félix Ávila Marcos dos Santos Lima Maria de Fátima Vanderlei de Souza Rita de Cássia Ramos do Egypto Queiroga 《Journal of Food Processing and Preservation》2021,45(4):e15265
67.
Antonino GenoveseNicola Contrisciani Fernando Ortenzi Vittorio Cazzola 《International Journal of Hydrogen Energy》2011,36(2):1775-1783
The promise of reducing harmful and CO2 emissions by focusing on hydrogen-methane blends (HCNG) have recently attracted the interest of vehicle manufacturers and transport operators. Several experiments have been conducted in laboratory facilities to assess the potential of HCNG blends in order to decrease the exhaust emissions. This paper reports the results of experimental tests performed at the ENEA Casaccia Research Center aiming to evaluate the energy and environmental performances of a CNG vehicle when fuelled with a hydrogen-methane blend. Two buses for urban transit service were fuelled with HCNG blends with different percentage of hydrogen (5%, 10%, 15%, 20% and 25% of hydrogen by volume). A 100% methane gas was used as reference to compare the advantages and disadvantages that can be derived from the use of HCNG blends. Road tests have been carried out by running fixed tracks, which are representative of urban and suburban driving cycles. Vehicles were powered with a lean burn engine whose setup - based on ignition advance angle, has been tuned for controlling the NOx emissions. CO2 emissions have been investigated to evaluate the leverage effect based on an increased CO2 reduction resulting from an increased engine efficiency. 相似文献
68.
González JM Cusumano A Williams HJ Colazza S Vinson SB 《Journal of chemical ecology》2011,37(6):629-639
Contact kairomones from the host mud dauber wasp Trypoxylon politum Say (Hymenoptera: Crabronidae) that mediate behavioral responses of its ectoparasitoid Melittobia digitata Dahms (Hymenoptera: Eulophidae) were investigated. Chemical residues from host by-products, the cocoon, and the meconium,
induced arrestment behavior of macropterous female parasitoids, while those from the host stage attacked, i.e., the prepupa,
did not. Melittobia digitata response to polar and apolar extracts of host by-products indicated kairomone(s) solubility mainly in hexane. GC and GC/MS
analysis of cocoon and meconium apolar extracts revealed a mixture of linear carboxylic acids from C6 to C18, and both extracts contained almost identical compounds. When a reconstructed blend of host by-product carboxylic acids was
tested, M. digitata females showed only a weak response, thus suggesting that other unidentified compounds present in small quantities also may
be involved. Melittobia digitata’s response to contact kairomones was innate and not affected by previous host exposure experience. Our results provide evidence
of contact kairomone exploitation in the genus Melittobia. The ecological significance of these findings in the host selection process of M. digitata is discussed. 相似文献
69.
Vittoria Cammisotto Francesco Baratta Valentina Castellani Simona Bartimoccia Cristina Nocella Laura DErasmo Nicholas Cocomello Cristina Barale Roberto Scicali Antonino Di Pino Salvatore Piro Maria Del Ben Marcello Arca Isabella Russo Francesco Purrello Roberto Carnevale Francesco Violi Daniele Pastori Pasquale Pignatelli 《International journal of molecular sciences》2021,22(13)
Background: Proprotein convertase subtilisin kexin type 9 inhibitors (PCSK9i) lower LDL-cholesterol and slow atherosclerosis preventing cardiovascular events. While it is known that circulating PCSK9 enhances platelet activation (PA) and that PCSK9i reduce it, the underlying mechanism is not still clarified. Methods: In a multicenter before–after study in 80 heterozygous familial hypercholesterolemia (HeFH) patients on treatment with maximum tolerated statin dose ± ezetimibe, PA, soluble-NOX2-derived peptide (sNOX2-dp), and oxidized-LDL (ox-LDL) were measured before and after six months of PCSK9i treatment. In vitro study investigates the effects of plasma from HeFH patients before and after PCK9i on PA in washed platelets (wPLTs) from healthy subjects. Results: Compared to baseline, PCSK9i reduced the serum levels of LDL-c, ox-LDL, Thromboxane (Tx) B2, sNOX2-dp, and PCSK9 (p < 0.001). The decrease of TxB2 correlates with that of ox-LDL, while ox-LDL reduction correlated with PCSK9 and sNOX2-dp delta. In vitro study demonstrated that wPLTs resuspended in plasma from HeFH after PCSK9i treatment induced lower PA and sNOX2-dp release than those obtained using plasma before PCSK9i treatment. This reduction was vanished by adding ox-LDL. ox-LDL-induced PA was blunted by CD36, LOX1, and NOX2 inhibition. Conclusions: PCSK9i treatment reduces PA modulating NOX2 activity and in turn ox-LDL formation in HeFH patients. 相似文献
70.
Solid state characterization of poly(L‐lysine)hydrobromide was obtained via differential scanning calorimetry, thermogravimetric analysis, optical microscopy and infrared spectroscopy. The glass transition temperature of poly(L‐lysine)hydrobromide is 178°C. This thermal transition has not been reported previously. Poly(L‐lysine)'s Tg decreases when complexes are produced with the following divalent transition metal chlorides; cobalt chloride hexahydrate, nickel chloride hexahydrate, copper chloride dihydrate and anhydrous zinc chloride. At 10 mol% salt, nickel, chloride decreases Tg by 45°C, and the general trend is Ni2+Co2+Zn2+Cu2+. The depression of poly(L‐lysine)'s Tg correlates well with ligand field stabilization energies for pseudo‐octahedral and pseudo‐tetrahedral dn complexes (n = 7, 8, 10) from the 1st row of the d‐block. However, d9 copper(II) complexes cannot be included in this empirical correlation. Infrared spectroscopic evidence suggests that Co2+, Ni2+ and Zn2+ coordinate to the carbonyl oxygen in the main chain of the polymer. When transition metal ions coordinate to C? O, the network of hydrogen bonded amide groups is disrupted, which lowers the glass transition. The amide I region of the infrared spectrum reveals a hydrogen bonded C? O stretch @ 1655 cm?1 that is characteristic of poly(α‐amino acid) random coil conformations, and a metal‐ligand coordinated C? O stretch @ 1625 cm?1 in complexes with divalent cobalt, nickel and zinc. The amide II region of the infrared spectrum near 1550 cm?1 is also sensitive to the formation of coordination complexes with these d‐block metal chlorides. 相似文献