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81.
Magdi M. Mossoba John K. G. Kramer Hormoz Azizian Jana Kraft Pierluigi Delmonte Ali-Reza Fardin Kia Francisco J. Bueso Jeanne I. Rader Jung K. Lee 《Journal of the American Oil Chemists' Society》2012,89(3):419-429
Since trans fat labeling requirements became mandatory in the US and many other countries, there has been a need for rapid and accurate
analytical methodologies that can facilitate compliance with the various regulations. The determination of total trans fatty acids by mid-infrared (IR) spectroscopy is a widely used procedure that was standardized and validated as AOCS Official
Method Cd 14e-09 (negative second derivative infrared spectroscopic method for the rapid (5 min) determination of total isolated
trans fat) in 2009. The C–H out-of-plane deformation mid-IR band observed at 966 cm−1 is uniquely characteristic of isolated (non-conjugated) double bonds with trans configuration. AOCS Official Method Cd 14e-09, the most recent attenuated total reflection-Fourier transform IR (ATR-FTIR)
official method, entails the measurement of the height of the negative second derivative of the trans absorption band. In the present study, the performance of a novel, portable FTIR system equipped with a heated 9-bounce diamond
ATR crystal was evaluated and compared to that of a conventional benchtop single-bounce ATR-FTIR spectrometer. The introduction
of the 9-bounce diamond ATR crystal resulted in the lowering of the limit of quantification of trans fat, as a percentage of the total fat, from approximately 2 to 0.34%. The data collected from accurately weighed gravimetric
standards and 28 unknown test samples ranging in trans fat content from about 0.5 to 54%, as a percentage of the total fat, indicated that this IR official method and the use of
the new 9-bounce portable ATR-FTIR instrumentation could lead to a five-fold enhancement in sensitivity relative to single-bounce
systems. Implementing these changes would facilitate regulatory compliance and verification of fat and oil samples for trans fat content in the US and other countries, since all of the published regulations (e.g., “0 g trans fat per serving”) have levels of trans fat, as percentage of total fat, that exceed 0.34%. 相似文献
82.
Jinggang Qin Yu Wu Min Yu Bo Liu Huajun Liu Klaus-Peter Weiss Laifeng Li Hongwei Li Erwu Niu Pierluigi Bruzzone 《Fusion Engineering and Design》2013,88(9-10):1461-1464
The ITER feeders are the components that connect the ITER magnet systems located inside the main cryostat to the cryogenics, power-supply and control system interfaces outside the cryostat. The feeder busbars rely on the Cable-In-Conduit Conductor (CICC) design concept as all the conductors for the ITER magnet systems. There are two types of busbars for the feeder systems. One is the Main Busbar (MB) for the TF, CS and PF feeders, and the other is the Corrector Busbar (CB) for the CC feeders. The busbar cable is wound from multiple stage sub-cables made with Cu and superconducting strands. The superconducting material is NbTi for the busbar strands of all feeder systems. All Feeder conductors are provided by China. The R&D programs are needed to acquire knowledge on the behavior of such conductors.Since the conductors are new, some full size copper dummy conductors have been produced for the testing of the cabling parameters, definition of automatic TIG welding of seamless jacket section, elaboration of cable insertion and compaction. Then, two short qualification conductor samples (MB and CB) are prepared in ASIPP, and NbTi advanced strands are produced by Western Superconductor Technology (WST).The details of manufacturing procedures for Feeder conductor samples will be described in this paper. 相似文献
83.
Rosamaria Lappano Camillo Rosano Antonio Madeo Lidia Albanito Pierluigi Plastina Bartolo Gabriele Luca Forti Lucia Anna Stivala Domenico Iacopetta Vincenza Dolce Sebastiano Andò Vincenzo Pezzi Marcello Maggiolini 《Molecular nutrition & food research》2009,53(7):845-858
Resveratrol (RSV) is classified as a phytoestrogen due to its ability to interact with estrogen receptors (ERs). We assessed structure–activity relationships of RSV and the analogs 4,4′‐dihydroxystilbene (4,4′‐DHS), 3,5‐dihydroxystilbene (3,5‐DHS), 3,4′‐dihydroxystilbene (3,4′‐DHS), 4‐hydroxystilbene (4‐HS) using as model systems the ERα‐positive and negative MCF7 and SkBr3 breast cancer cells, respectively. In binding assays and transfection experiments RSV and the analogs showed the following order of agonism for ERα: 3,4′‐DHS > 4,4′‐DHS > 4‐HS > RSV, while 3,5‐DHS did not elicit any ligand properties. Computational docking analysis and real‐time PCR revealed for each analog a distinct ERα binding orientation and estrogen target gene expression profile. Interestingly, the aforementioned order of ligand activity was confirmed in proliferation assays which also showed the lack of growth stimulation by 3,5‐DHS. Our data suggest that subtle changes in the structure of the RSV derivatives examined may be responsible for the different ERα‐mediated biological responses observed in estrogen‐sensitive cancer cells. 相似文献
84.
This work investigates the behaviour of planar solid oxide fuel cells (SOFCs) fed by two different fuel mixtures that simulate biogases coming from anaerobic digestion. The fuel mixtures are namely bio-methane and bio-hydrogen. The first composition is the conventional one, where a biological process of fermentation is carried out to produce a gas that contains a mixture of methane and carbon dioxide with traces of H2S and other organic sulphur compounds. The second mixture is representative of a biogas produced through a novel routine: a particular pre-treatment of the bacteria inoculum (generally clostridia bacteria) is performed in order to inhibit the methanogenic step in the fermentation process, such that bio-hydrogen is produced as the only effluent of the digester (a mixture of H2/CO2, with no traces of methane). 相似文献
85.
Pierluigi Paris Leonardo MareschiMaurizio Sabatti Andrea PisanelliAlfredo Ecosse Fabrizio NardinGiuseppe Scarascia-Mugnozza 《Biomass & bioenergy》2011,35(4):1524-1532
Short rotation forest (SRF) plantations of hybrid poplars are attractive for Italian farmers due to the availability of public grants and the potential for producing wood chips for energy production. Growth and dendromass yield of new clones for SRF were evaluated after two biennial rotations within a network of experimental fields established in 2003 on three sites of low (Bigarello), medium (Vinovo) and high soil quality (Mira), across northern Italy. Soil preparation, planting density (5900 trees ha−1), weed control, tree water status and mechanical harvesting were homogeneous across the sites. Nitrogen fertilization was applied only in Mira (300 kg N ha−1).In all sites, survival was high for almost all clones, and stem density increased dramatically, with a decrease of stem dimensions, after the first coppicing. In Bigarello, with limiting soil conditions, there was no significant difference among clone biennial yields, which varied from 10.3 (first rotation) to 14.2 (second rotation) Mg ha−1 in dry matter (dm). In the medium and high quality sites of Vinovo and Mira, there was a significant difference in clone yields, with the new clones performing better than control clones (I-214 and Lux). In Mira, mean biennial yield increased from 30.2 to 40.3 Mg dm ha−1 from the first to second cycle.Preliminary results of new clones on medium and high soil quality need to be further confirmed throughout further coppicing cycles; on a marginal soil, even by using the new clones, poplar SRF is not an advisable option. 相似文献
86.
Bonding between the adherents represents a key point when dealing with the reinforcement of concrete structures by using FRPs. Bonding depends on mechanical and physical properties of concrete, composite and adhesive as well as on the surface treatment of the concrete substrate. A very important topic for civil engineering applications is related to the durability of the bond in harsh environments. In the present paper some specimens were first subjected to freeze–thaw cycles and then experimental debonding tests were performed in order to investigate the effects of the bonding length and environmental conditions. First, the effects of environmental conditions on bond strength is discussed. Finally, the experimental data are compared to the design formulae proposed by the Italian Recommendations CNR DT200/2004 and critical considerations are presented. 相似文献
87.
Erika Ponzini Diletta Ami Alessandro Duse Carlo Santambrogio Antonella De Palma Dario Di Silvestre Pierluigi Mauri Fabio Pezzoli Antonino Natalello Silvia Tavazzi Rita Grandori 《International journal of molecular sciences》2021,22(19)
Lacrimal fluid is an attractive source of noninvasive biomarkers, the main limitation being the small sample amounts typically collected. Advanced analytical methods to allow for proteomics profiling from a few microliters are needed to develop innovative biomarkers, with attractive perspectives of applications to precision medicine. This work describes an effective, analytical pipeline for single-tear analysis by ultrahigh-resolution, shotgun proteomics from 23 healthy human volunteers, leading to high-confidence identification of a total of 890 proteins. Highly reproducible quantification was achieved by either peak intensity, peak area, or spectral counting. Hierarchical clustering revealed a stratification of females vs. males that did not emerge from previous studies on pooled samples. Two subjects were monitored weekly over 3 weeks. The samples clustered by withdrawal time of day (morning vs. afternoon) but not by follow-up week, with elevated levels of components of the immune system in the morning samples. This study demonstrates feasibility of single-tear quantitative proteomics, envisaging contributions of this unconventional body fluid to individualized approaches in biomedicine. 相似文献
88.
Federico Pazzagli Massimo Paci Pierluigi Magagnini Ugo Pedretti Carlo Corno Guglielmo Bertolini Carlo A. Veracini 《应用聚合物科学杂志》2000,77(1):141-150
The melt polycondensation of mixtures of sebacic acid (S), 4,4′‐diacetoxybiphenyl (B), and 4‐acetoxybenzoic acid (H), carried out for the synthesis of semiflexible liquid–crystalline copolyesters referred to as SBH 1 : 1 : x, has been studied with the aim of clarifying the effect of the reaction conditions on the microstructure and the thermal properties of the products. It has been shown that the segregation of a liquid–crystalline phase within the polymerizing mixture, coupled with the thermodynamic tendency of the two phases to undergo compositional differentiation as polymerization proceeds, is responsible for the formation of blocky, rather than ideally random, copolyesters with poor processibility, when the mole ratio of H to the other two monomers is higher than x ≈ 1.90. The results of this study have shown that this unwanted effect can be considerably limited by carrying out the polycondensation at a relatively high temperature from the very beginning, rather than by the standard technique involving progressive heating of the reaction mixture, thus allowing the production of SBH copolyesters with a higher degree of aromaticity. The results are discussed in terms of the relative rates of the condensation reactions, which are responsible for chain growth, and of the concurrent acidolysis and esterolysis reactions leading to copolyester sequence reorganization. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 141–150, 2000 相似文献
89.
Valentina Marassi Stefano Giordani Andjela Kurevija Emilio Panetta Barbara Roda Nan Zhang Andrea Azzolini Sara Dolzani Dmytro Manko Pierluigi Reschiglian Mauro Atti Andrea Zattoni 《International journal of molecular sciences》2022,23(24)
Dissolved oxygen (DO) is deeply involved in preserving the life of cellular tissues and human beings due to its key role in cellular metabolism: its alterations may reflect important pathophysiological conditions. DO levels are measured to identify pathological conditions, explain pathophysiological mechanisms, and monitor the efficacy of therapeutic approaches. This is particularly relevant when the measurements are performed in vivo but also in contexts where a variety of biological and synthetic media are used, such as ex vivo organ perfusion. A reliable measurement of medium oxygenation ensures a high-quality process. It is crucial to provide a high-accuracy, real-time method for DO quantification, which could be robust towards different medium compositions and temperatures. In fact, biological fluids and synthetic clinical fluids represent a challenging environment where DO interacts with various compounds and can change continuously and dynamically, and further precaution is needed to obtain reliable results. This study aims to present and discuss the main oxygen detection and quantification methods, focusing on the technical needs for their translation to clinical practice. Firstly, we resumed all the main methodologies and advancements concerning dissolved oxygen determination. After identifying the main groups of all the available techniques for DO sensing based on their mechanisms and applicability, we focused on transferring the most promising approaches to a clinical in vivo/ex vivo setting. 相似文献
90.
Trigeneration or combined heat, cooling and power (CHCP) is becoming an increasingly important energy option, particularly on a small-scale basis (below 1 MWe), with several alternatives nowadays available for the cooling power production and the coupling to cogeneration systems. This paper deals with the introduction of a suitable framework for assessing the energy saving performance of trigeneration alternatives, orientated towards energy planning studies and the development of regulatory policies. In particular, a new generalized performance indicator—the trigeneration primary energy saving (TPES)—is introduced and discussed, with the aim of effectively evaluating the primary energy savings from different CHCP alternatives. The potential of the TPES indicator is illustrated through specific analyses run over different combinations of trigeneration equipment, providing numerical examples based on time-domain simulations to illustrate the dependence of the energy saving characteristics on the CHCP system configurations and equipment, as well as on the loading levels. In addition, the key aspect of adequately establishing the reference efficiencies for the conventional separate production of electrical, thermal and cooling power is addressed in detail. This aspect affects both equipment selection and potential profitability of the considered solutions under the outlook of receiving financial incentives. 相似文献