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1.
Tight control of flux loci in 2D testing of soft magnetic laminations is realized by a method based on the principle of contraction mapping. It is implemented through digital control of the currents supplying a three-phase yoke magnetizer and the use of circular samples. Faithful realization of the prescribed loci and good measuring accuracy are demonstrated in grain-oriented and non-oriented Fe–Si laminations. 相似文献
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Presti ML Ragusa S Trozzi A Dugo P Visinoni F Fazio A Dugo G Mondello L 《Journal of separation science》2005,28(3):273-280
Traditional hydrodistillation (HD), supercritical fluid extraction (SFE), organic solvent extraction (SE), and water microwave assisted hydrodistillation (MAHD) techniques were compared and evaluated for their effectiveness in the isolation of rosemary essential oil. The microwave assisted hydrodistillation technique was optimized in terms of both delivered power and time duration. The extracts/distillates were analyzed by GC and GC-MS. Microwave distillation, which exploits the physical action of microwaves on plants, showed a series of advantages over the other approaches: low cost, use of water in sample pre-treatment step, greatly reduced isolation time, and attainment of high quality essential oil distillate. Moreover, the absence of environmental impact of this innovative technique was also emphasized. 相似文献
4.
Biswajita Pradhan Srimanta Patra Chhandashree Behera Rabindra Nayak Bimal Prasad Jit Andrea Ragusa Mrutyunjay Jena 《Molecules (Basel, Switzerland)》2021,26(4)
Marine algae are a promising source of potent bioactive agents against oxidative stress, diabetes, and inflammation. However, the possible therapeutic effects of many algal metabolites have not been exploited yet. In this regard, we explored the therapeutic potential of Enteromorpha intestinalis extracts obtained from methanol, ethanol, and hexane, in contrasting oxidative stress. The total phenolic (TPC) and flavonoids (TFC) content were quantified in all extracts, with ethanol yielding the best values (about 60 and 625 mg of gallic acid and rutin equivalents per gram of extract, respectively). Their antioxidant potential was also assessed through DPPH•, hydroxyl radical, hydrogen peroxide, and superoxide anion scavenging assays, showing a concentration-dependent activity which was greater in the extracts from protic and more polar solvents. The α-amylase and α-glucosidase activities were estimated for checking the antidiabetic capacity, with IC50 values of about 3.8 µg/mL for the methanolic extract, almost as low as those obtained with acarbose (about 2.8 and 3.3 µg/mL, respectively). The same extract also showed remarkable anti-inflammatory effect, as determined by hemolysis, protein denaturation, proteinase and lipoxygenase activity assays, with respectable IC50 values (about 11, 4, 6, and 5 µg/mL, respectively), also in comparison to commercially used drugs, such as acetylsalicylic acid. 相似文献
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P.L. Frabetti G. Bellini T. Bettinazzi M. Di Corato E. Meroni S. Micheletti F. Palombo F. Ragusa P.G. Rancoita G. Vegni L. Chernenko Yu. Ivanshin I. Pisarev S. Sychkov A. Tjapkin V. Vishniakov O. Zaimidoroga P.F. Manfredi 《Nuclear Physics B》1979,158(1):57-70
In the frame of a systematic study of hadron-nucleus interactions performed at the Serpukhov accelerator (CERN-IHEP 5th experiment), semicoherent elastic scattering on carbon was investigated with 25 and 40 GeV/c incident pions.The experimental data were obtained with a counter technique, looking at the coincidence between the scattered pion and the 4.44 MeV photon from the JP = 2+ carbon excited state detected by a NaI counter.The value obtained for the integrated cross section at 40 GeV/c in the 0.0032 ? |t| ? 0.27 (GeV/c)2 four-momentum transfer range isσ = 1.16 ± 0.11 mb.According to the theoretical models, this t-range at 40 GeV/c covers more than 99% of the angular distribution, so the above value almost corresponds to the total semicoherent elastic cross section. 相似文献
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Maria Alessandra Ragusa 《Journal of Global Optimization》2008,40(1-3):361-368
In this note we prove a sufficient condition for commutators of fractional integral operators to belong to Vanishing Morrey
spaces VL
p,λ. In doing this we use an extension on Morrey spaces of an inequality by Fefferman and Stein concerning the sharp maximal
function and the fractional maximal function and related Morrey inequalities.
相似文献
8.
We deal with the weak Lefschetz property (WLP) for Artinian standard graded Gorenstein algebras of codimension 3. We prove that many Gorenstein sequences force the WLP for such algebras. Moreover for every Gorenstein sequence \(H\) of codimension 3 we found several Gorenstein Betti sequences compatible with \(H\) which again force the WLP. Finally we show that for every Gorenstein Betti sequence the general Artinian standard graded Gorenstein algebra with such Betti sequence has the WLP. 相似文献
9.
The solar gravitational deflection angle of a graviton is calculated through the scattering cross section of the graviton by the sun and shown to be equal to the light deflection angle as calculated from the null geodesic equation of general relativity. 相似文献
10.
For a smooth irreducible complete algebraic curveC the “gaps” are the integersn such that every linear series of degreen has at least a base point. The Lüroth semigroup SC of a curveC is the subsemigroup ofN whose elements are not gaps. In this paper we deal with irreducible smooth curves of type (a, b) on a smooth quadricQ. The main result is an algorithm by which we can say if some integer λ∈N is a gap or is in SC. In the general case there are integers λ which are undecidable. For curves such as complete intersection, arithmetically
Cohen-Macaulay or Buchsbaum, we are able to describe explicitly “intervals” of gaps and “intervals” of integers which belong
to SC. For particular cases we can completely determine SC, by giving just the type of the curve (in particular the degree and the genus).
Work done with financial support of M.U.R.S.T. while the authors were members of G.N.S.A.G.A. of C.N.R. 相似文献