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61.
As a perturbation to the P(?)2 theory we consider interaction densities of the form V(?(x)), where ?(x) is a scalar hermitian boson field and V(α) is a bounded real continuous function. It is proved that the asymptotic fields exist and are equal to the asymptotic fields of the P(?)2 theory. The connection with non-polynomial theories of rational type is indicated. Furthermore the consequences of a bounded perturbation for the S-matrix and the spectral properties are discussed. 相似文献
62.
Two losing gambling games, when alternated in a periodic or random fashion, can produce a winning game. This paradox has been inspired by certain physical systems capable of rectifying fluctuations: the so-called Brownian ratchets. In this paper we review this paradox, from Brownian ratchets to the most recent studies on collective games, providing some intuitive explanations of the unexpected phenomena that we will find along the way. 相似文献
63.
Hasliza Hassan Mohd Din Amiruddin Wolfram Weckwerth Umi Salamah Ramli 《Electrophoresis》2019,40(2):254-265
Palm oil is an edible vegetable oil derived from lipid‐rich fleshy mesocarp tissue of oil palm (Elaeis guineensis Jacq.) fruit and is of global economic and nutritional relevance. While the understanding of oil biosynthesis in plants is improving, the fundamentals of oil biosynthesis in oil palm still require further investigations. To gain insight into the systemic mechanisms that govern oil synthesis during oil palm fruit ripening, the proteomics approach combining gel‐based electrophoresis and mass spectrometry was used to profile protein changes and classify the patterns of protein accumulation during these complex physiological processes. Protein profiles from different stages of fruit ripening at 10, 12, 14, 15, 16, 18 and 20 weeks after anthesis (WAA) were analysed by two‐dimensional gel electrophoresis (2DE). The proteome data were then visualised using a multivariate statistical analysis of principal component analysis (PCA) to get an overview of the proteome changes during the development of oil palm mesocarp. A total of 68 differentially expressed protein spots were successfully identified by matrix‐assisted laser desorption/ionisation‐time of flight (MALDI‐TOF/TOF) and functionally classified using ontology analysis. Proteins related to lipid production, energy, secondary metabolites and amino acid metabolism are the most significantly changed proteins during fruit development representing potential candidates for oil yield improvement endeavors. Data are available via ProteomeXchange with identifier PXD009579. This study provides important proteome information for protein regulation during oil palm fruit ripening and oil synthesis. 相似文献
64.
Filiz Ercan S. Gül Öztas Nilgün Ancm Tuncer Hökelek Mürside Tüzün Dinçer Ülkü 《Journal of chemical crystallography》1996,26(3):243-247
N-trans-cinnamylidene-m-toluidine (1) C16H15N, and N-trans-cinnamylidene-m-chloroaniline (2) C15H12NCl form isomorphous crystals which are monoclinic, space group P2l/c, with unit cell dimensionsa=5.967(2),b=13.793(3),c=15.048(5) Å, =91.97(3)° anda=5.868(2),b=13.788(4),c=15.191(4) Å, =91.87(3)°, respectively. The single-crystal X-ray structure determinations of the title compounds revealtrans structures. Ring (A) C10–15 and ring (B) C1–6, are practically planar in both structures with dihedral angels of 61.3(3) and 63.6(2)°, respectively.1H nmr, u.v. and i.r. spectra are also reported. 相似文献
65.
66.
Safaa El-Nahas Abdulrahem S. Arafat Hanan Salah El Din Abdulrahman G. Alhamzani Mortaga M. Abou-Krisha Hesham M. Alsoghier 《Molecules (Basel, Switzerland)》2021,26(22)
The strategic idea in this work was to increase pH values by employing natural alkali sources (i.e., HCO3− and CO32−) from four tested agro-ashes as an alternative to chemicals (i.e., lime or soda ash). The considerable proportion of carbonates and bicarbonates in the investigated ash products had remarkable features, making them viable resources. All ash materials showed a significant ability for Ca ion elimination at high initial Ca ion concentrations. A slight quantity of ash (10 g/L) was sufficient for usage on very hard water contents up to 3000 ppm. Finally, the tested agro-ash was free of cost. Furthermore, unlike other conventional precipitants, such as NaOH, Ca(OH)2, NaHCO3, Na2CO3, and CaO, they are cost effective and ecologically sustainable. There is no need to employ any additional chemicals or modify the agro-ash materials throughout the treatment process. The benefits of the manufactured ash were assessed using a SWOT analysis. 相似文献
67.
The effect of a Mach wave (N wave) on laminar-turbulent transition induced by the first instability mode (Tollmien–Schlichting wave) in the flat-plate boundary layer is investigated on the basis of the numerical solution of Navier–Stokes equations at the freestream Mach number of 2.5. In accordance with the experiment, the N wave is generated by a two-dimensional roughness at the computation domain boundary corresponding to the side wall of the test section of a wind tunnel. It is shown that the disturbance induced by the backward front of the N wave in the boundary layer has no effect on the beginning of transition but displaces downstream the nonlinear stage of the first mode development. The disturbance induced by the forward front of the N wave displaces the beginning of transition upstream. 相似文献
68.
We present a comparative study on the enhancement of photoluminescence and Raman processes by a single metal nanoparticle. Taking an analytical approach, we show the physics behind strikingly different orders of magnitude in enhancement that have been observed, provide fundamental explanation for not observing quenching of Raman processes, and outline the path to optimization of both photoluminescence and Raman enhancement. 相似文献
69.
Dinçer Ülkü Leyla Tatar Orhan Atakol Mecit Aksu 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(3):273-274
In the title linear trinuclear compound, [Zn{Zn(CH3COO)(C17H16N2O2)}2], the central Zn2+ ion, which is located on an inversion centre, has a distorted octahedral coordination involving four bridging O atoms from two N,N′-bis(salicylidene)-1,3-propanediaminate ligands in the equatorial plane and one O atom from each bridging acetate group in the axial positions. The coordination around the terminal Zn2+ ion is irregular square pyramidal, with two O and two N atoms of the ligand in the basal plane and one O atom from an acetate group in the apical position. The acetate bridges linking the central and terminal Zn2+ ions are mutually trans. The Zn⃛Zn distance is 3.0520 (8) Å. The relationship of this structure to that of [Zn{Cu(CH3COO)(C17H16N2O2)}2] is discussed. 相似文献
70.