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61.
Cristina Occhiuto Gianluigi Aliberto Mariarosaria Ingegneri Domenico Trombetta Clara Circosta Antonella Smeriglio 《Molecules (Basel, Switzerland)》2022,27(11)
Recently, there has been a growing interest in the recovery of agri-food waste within the circular economy perspective. In this study, the nutritional, phytochemical, and biological features of the cold-pressed hempseed oil (HSO) and hempseed meal (HSM) of two industrial hemp varieties (USO 31 and Futura 75, THC ≤ 0.2%) were evaluated. The HSOs showed a high total phenols and flavonoid content, which were confirmed by LC-DAD-ESI-MS analysis, with rutin as the most abundant compound (56.93–77.89 µg/100 FW). They also proved to be a rich source of tocopherols (81.69–101.45 mg/100 g FW) and of a well-balanced ω-6 to ω-3 fatty acid ratio (3:1) with USO 31, which showed the best phytochemical profile and consequently the best antioxidant activity (about two times higher than Futura 75). The HSMs still retained part of the phytochemicals identified in the HSOs (polyphenols, tocopherols, and the preserved ω-6/ω-3 fatty acids ratio) and a modest antioxidant activity. Furthermore, they showed a very interesting nutritional profile, which was very rich in proteins (29.88–31.44 g/100 g FW), crude fibers (18.39–19.67 g/100 g), and essential and non-essential amino acids. Finally, only a restrained amount of anti-nutritional factors (trypsin inhibitors, phytic acid, and condensed tannins) was found, suggesting a promising re-use of these byproducts in the nutraceutical field. 相似文献
62.
A GC method to determine caprolactam in water, 15% ethanol, and olive oil food simulants was developed and validated. Linear ranges varied from 0.96 to 642.82 microg/mL for water, 0.64 to 800.32 microg/mL for 15% ethanol, and 1.06 to 1062.34 microg/g for olive oil, with correlation coefficients higher than 0.999. Method precision studies showed RSD values lower than 5.45%, while method accuracy studies showed recovery from 72 to 111% for all simulants. The effect of gamma irradiation on caprolactam migration from multilayer polyamide 6 (PA-6) films intended for cheese into water, 15% ethanol, olive oil, and 3% acetic acid simulants was also studied. For migration assay, non-irradiated and irradiated (12 kGy) films were placed in contact with the simulant and exposed at 40 degrees C for 10 days. The validated method was used to quantify caprolactam migration from multilayer PA-6 films into the simulants, which ranged from 1.03 to 7.59 mg/kg for non-irradiated films, and from 4.82 to 11.32 mg/kg for irradiated films. Irradiation caused almost no changes in caprolactam levels, with the exception of olive oil, which showed an increase in the caprolactam level. All multilayer PA-6 films were in accordance with the requirements of the legislation for caprolactam migration. 相似文献
63.
Giovanni Maglio Rosario Palumbo Mariarosaria Tortora 《Journal of polymer science. Part A, Polymer chemistry》2000,38(7):1172-1178
Poly(arylether benzoxazole)s (PAEBOs) were prepared from a series of fully aromatic dicarboxylic acids containing (phenylenedioxy)diphenylene or (naphthalenedioxy) diphenylene groups and 3,3′‐dihydroxy‐4,4′‐diaminobiphenyl (I) or 4‐4′‐(hexafluoroisopropylidene)bis(2‐aminophenol) (II) through high‐temperature direct polycondensation. A phosphorous pentoxide/methanesulfonic acid mixture or trimethylsilylpolyphosphate was used as a condensing agent. All the PAEBOs were amorphous and soluble in strong acids, and those derived from II were also readily soluble in polar organic solvents. Flexible films were cast from their chloroform solutions. The PAEBOs showed inherent viscosity values of 0.68–2.06 dL/g (CH3SO3H, T = 30 °C, c = 0.15 g · dL−1). Thermal analysis indicated glass‐transition temperatures ranging from 236 to 270 °C and thermal stability (5% weight loss) in nitrogen up to 526 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1172–1178, 2000 相似文献
64.
Natale Badalamenti Maurizio Bruno Rosario Schicchi Anna Geraci Mariarosaria Leporini Rosa Tundis Monica Rosa Loizzo 《Molecules (Basel, Switzerland)》2022,27(10)
The aim of the present study is to investigate the chemical profile, antioxidant activity, carbohydrate-hydrolysing enzyme inhibition, and hypolipidemic effect of essential oils (EOs) extracted from Sicilian Citrus maxima (pomelo) flavedo. Using gas-chromatography-mass spectrometry analysis (GC-MS) we analysed the Eos of five cultivars of C. maxima, namely, ‘Chadock’, ‘Maxima’, ‘Pyriformis’, ‘Terracciani’, and ‘Todarii’, and their blends. The antioxidant activity was performed by using a multi-target approach using 2,2′-Azino-Bis-3-Ethylbenzothiazoline-6-Sulfonic acid (ABTS), 2,2-Diphenyl-1-picrylhydrazyl (DPPH), ferric reducing ability power (FRAP), and β-carotene bleaching tests. The α-amylase, α-glucosidase, and lipase-inhibitory activities were also assessed. GC-MS analyses revealed D-limonene as the main monoterpene hydrocarbon in all cultivars, albeit with different percentages in the range of 21.72–71.13%. A good content of oxygenated monoterpenes was detected for all cultivars, especially for ‘Todarii’. The analysis of the principal components (PCA), and related clusters (HCA), was performed to find chemo-diversity among the analysed samples. EOs from ‘Chadock’ and ‘Maxima’ were statistically similar to each other, and they differed from P3 in the smaller amount of sesquiterpene hydrocarbons, while the oils from ‘Terracciani’ and ‘Todarii’ were found to be chemically and statistically different. ‘Chadock’ EO was the most active to scavenge radicals (IC50 values of 22.24 and 27.23 µg/mL in ABTS and DPPH tests, respectively). ‘Terracciani’ EO was the most active against both lipase and α-amylase, whereas the blends obtained by the combination (1:1 v/v) of C. maxima ‘Maxima’ + ‘Todarii’ were the most active against α-glucosidase. Generally, the blends did not exert a unique behaviour in potentiating or reducing the bioactivity of the pomelo EOs. 相似文献
65.
Antonín Novotný Mariarosaria Padula 《Archive for Rational Mechanics and Analysis》1994,126(3):243-297
We investigate steady compressible flows in three-dimensional exterior domains for small data and for both zero and nonzero (but constant) velocity at infinity. We prove existence and uniqueness of solutions in L
p
-spaces, p>3, and study their regularity as well as their decay at infinity. 相似文献
66.
A versatile cost‐effective method for the analysis of fresh frozen tissue sections via matrix‐assisted laser desorption/ionisation imaging mass spectrometry 下载免费PDF全文
67.
Poly(epsilon-caprolactone) (PCL) macromers (M(n) = 1.7-3.8 kDa) which contain one Z-protected -NH2 group per chain were synthesized by ring-opening polymerization of epsilon-caprolactone in the presence of Sn(oct)2 using as initiator a diamine prepared by condensation of N-Boc-1,6-hexanediamine and N(alpha)-Boc-N(epsilon)-Z-L-Lysine. The coupling of these macromers with -COCl end-capped poly(oxyethylene) (PEO), M(n) = 1.0 kDa, afforded amphiphilic multiblock poly(ether ester)s (PEEs) which have, along the chain, regularly spaced pendant protected amino groups. Deprotection, accomplished without chain degradation, yielded -NH2 groups available for further reactions. The molecular structure of macromers and PEEs was investigated by 1H NMR and SEC. DSC and WAXS analyses showed that macromers and copolymers were semicrystalline and their T(m) increased with increase in the molecular weight of PCL segments. The inherent viscosity values (0.25-0.30 dL x g(-1)), together with SEC analysis results, indicated moderate polymerization degrees. 相似文献
68.
Methods of preparation of novel composites of poly(ϵ‐caprolactone) and a modified Mg/Al hydrotalcite
Loredana Tammaro Mariarosaria Tortora Vittoria Vittoria Umberto Costantino Fabio Marmottini 《Journal of polymer science. Part A, Polymer chemistry》2005,43(11):2281-2290
12‐Hydroxydodecanoate (HD) anions were intercalated, via an ion‐exchange procedure, onto a Mg/Al hydrotalcite‐like compound with the formula [Mg0.65Al0.35(OH)2](NO3)0.35·0.56H2O. The obtained intercalate, characterized by chemical and thermal analyses, X‐ray powder diffraction, and Fourier transform infrared spectroscopy, had the formula [Mg0.65Al0.35(OH)2](NO3)0.08(HD)0.28·0.56H2O and an interlayer distance of 2.27 nm. Structural considerations indicated that the charge‐balancing HO? (CH2)11? COO? anions were accommodated in the interlayer region as a monofilm of partially interdigitated alkyl chains in a trans planar conformation and bearing the alcoholic group. The organically modified hydrotalcite was used to prepare novel composites based on poly(?‐caprolactone) (PCL) with different procedures: (1) solvent casting, (2) ring‐opening polymerization of ?‐caprolactone, and (3) blending of precursors consisting of a PCL intercalated oligomer with a high‐molecular‐weight PCL. Microcomposites were obtained by the solvent casting of a mixture of a high‐molecular‐weight PCL and the modified hydrotalcite. The ring‐opening polymerization of ?‐caprolactone initiated by the ? OH groups of the alkyl chains intercalated in the hydrotalcite led to hybrid materials in which a low‐molecular‐weight PCL was in part intercalated into the modified hydrotalcite. Nanocomposites containing exfoliated hydrotalcite were obtained through the mixing, in different weight ratios, of hybrids consisting of PCL oligomers and modified hydrotalcite with a commercial high‐molecular‐weight PCL. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2281–2290, 2005 相似文献
69.
M. Padula 《Annali dell'Universita di Ferrara》2003,49(1):375-396
LetC
* be a equilibrium configuration of a thermo-visco-elastic material. The paper aims to reach three objectives; i) control of
perturbations toC
* in terms of the data, if forces are conservatives, andC
* is a local proper minimum for the total energy ε; ii) asymptotic decay to zero of perturbations toC
*, in case of dissipative systems ifC
* is a local proper minimum for ε; iii) non-linear instability, if forces are conservatives, andC
* is a local proper maximum for ε. In order to reach these goals we adopt qualitative methods in the wake of direct Lyapunov
methods. Precisely, first we use the concept of power to construct a Lyapunov functional appropriate to furnish stability
in the mean (control of perturbations to velocity and positions), when ε has a minimum atC
*; then introducing thefree work we deduce apivot equation for the study of nonlinear stability. In particular, the pivot equation provides and asymptotic stability for dissipative
systems towardC
*, ifC
* is a local proper minimum for the total energy, and furnishes non-linear instability ofC
*, ifC
* is a local proper maximum for the total energy as well. Our results apply to rigorous nonlinear equations of motion, with
non-linear constitutive equations. The results are a consequence of the D'Alambert-Lagrange equation.
Sunto SiaC * una configurazione di equilibrio di un materiale termo-visco-elastico. Questa nota intende raggiungere tre obiettivi: i) controllo delle perturbazioni aC * in termini dei dati, se le forze sono conservative, seC * è un minimo locale proprio per l'energia totale ε; ii) decadimento asintotico a zero delle perturbazioni aC *, nel caso di sistemi dissipativi, seC * è un minimo locale proprio per ε; iii) instabilità non-lineare, se le forze sono conservative, eC * è un massimo locale proprio per ε. Al fine di raggiungere questi obiettivi si adottano metodi qualitativi sulla scia dei metodi diretti di Lyapunov. Precisamente, dapprima si usano il concetto di potenza per costruire un funzionale di Lyapunov appropriato per lo studio della stabilità in media (controllo delle perturbazioni alle velocità e posizioni delle particelle), nel caso in cui ε abbia un minimo inC *; in seguito introducendo il nuovo lavoro piattaformafree work, si deduce una equazione piattaforma di lanciopivot equation per lo studio della stabilità nonlineare. In particolare, l'equazione piattaforma di lancio fornisce simultaneamente: stabilità asintotica per sistemi dissipativi versoC *, seC * è un minimo locale proprio per l'energia totale; instabilità della posizioneC *, seC * risulta un massimo locale proprio per l'energia totale. Detto risultato vale per equazioni di moto, rigorose nonlineari, quando si adottano equazioni costitutive nonlineari per il materiale. I risultati sono una conseguenza dell'equazione di D'Alambert-Lagrange per il lavoro elementare.相似文献
70.
Mariarosaria Padula 《Meccanica》1981,16(3):128-135
Summary We prove existence and continuous dependence of solutions to one-dimensional motions of a politropic viscous gas in arbitrary regions. In particular, in case of unbounded regions we do not assume the initial density distribution to have a strict positive lower bound.
This work has been realized within the activities of the Italian Council for the Research (C.N.R.), gruppo nazionale della fisica matematica (G.N.F.M.). 相似文献
Sommario Proviamo l'esistenza e la dipendenza continua di soluzioni per i moti unidimensionali di un gas viscoso politropico in regioni arbitrarie. In particolare, nel caso in cui la regione del moto è non limitata, non assumiamo che la distribuzione di densità all'istante iniziale abbia estremo inferiore strettamente positivo.
This work has been realized within the activities of the Italian Council for the Research (C.N.R.), gruppo nazionale della fisica matematica (G.N.F.M.). 相似文献