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101.
Jawaher Ayadi Mohamed Debouba Rami Rahmani Jalloul Bouajila 《Molecules (Basel, Switzerland)》2022,27(18)
Traditionally, Brassica species are widely used in traditional medicine, human food, and animal feed. Recently, special attention has been dedicated to Brassica seeds as source of health-promoting phytochemicals. This review provides a summary of recent research on the Brassica seed phytochemistry, bioactivity, dietary importance, and toxicity by screening the major online scientific database sources and papers published in recent decades by Elsevier, Springer, and John Wiley. The search was conducted covering the period from January 1964 to July 2022. Phytochemically, polyphenols, glucosinolates, and their degradation products were the predominant secondary metabolites in seeds. Different extracts and their purified constituents from seeds of Brassica species have been found to possess a wide range of biological properties including antioxidant, anticancer, antimicrobial, anti-inflammatory, antidiabetic, and neuroprotective activities. These valuable functional properties of Brassica seeds are related to their richness in active compounds responsible for the prevention and treatment of various chronic diseases such as obesity, diabetes, cancer, and COVID-19. Currently, the potential properties of Brassica seeds and their components are the main focus of research, but their toxicity and health risks must also be accounted for. 相似文献
102.
Ali Bahadur Tehseen Ali Anjum Mah Roosh Shahid Iqbal Hamad Alrbyawi Muhammad Abdul Qayyum Zaheer Ahmad Murefah Mana Al-Anazy Eslam B. Elkaeed Rami Adel Pashameah Eman Alzahrani Abd-ElAziem Farouk 《Molecules (Basel, Switzerland)》2022,27(20)
Tungsten trioxide (WO3) is mainly studied as an electrochromic material and received attention due to N-type oxide-based semiconductors. The magnetic, structural, and optical behavior of pristine WO3 and gadolinium (Gd)-doped WO3 are being investigated using density functional theory. For exchange-correlation potential energy, generalized gradient approximation (GGA+U) is used in our calculations, where U is the Hubbard potential. The estimated bandgap of pure WO3 is 2.5 eV. After the doping of Gd, some states cross the Fermi level, and WO3 acts as a degenerate semiconductor with a 2 eV bandgap. Spin-polarized calculations show that the system is antiferromagnetic in its ground state. The WO3 material is a semiconductor, as there is a bandgap of 2.5 eV between the valence and conduction bands. The Gd-doped WO3’s band structure shows few states across the Fermi level, which means that the material is metal or semimetal. After the doping of Gd, WO3 becomes the degenerate semiconductor with a bandgap of 2 eV. The energy difference between ferromagnetic (FM) and antiferromagnetic (AFM) configurations is negative, so the Gd-doped WO3 system is AFM. The pure WO3 is nonmagnetic, where the magnetic moment in the system after doping Gd is 9.5599575 μB. 相似文献
103.
104.
The relative free energy difference (ΔΔGhyd) for the reversible addition of water to two unsaturated molecules is accurately computed using a combination of ab initio quantum mechanical calculations and free energy perturbation methods. Initial attempts to calculate the absolute hydration free energy difference (ΔGhyd) for formaldehyde and trichloroacetaldehyde gave values that differed substantially from experimental results even after inclusion of electron correlation energy contributions using third-order (MP3) and fourth-order (MP4) Møller-Plesset perturbation theory and QCISD(T) correlation methods at the 6-31G** basis set level. Inaccuracies in ΔGhyd were attributed to errors in the calculation of both ΔGgas and ΔΔGsol. Gas phase quantum mechanical free energies (ΔGgas) varied significantly (2–3 kcal/mol) depending on the level of theory. Errors in ΔΔGsol were attributed to slow convergence of the calculations using the thermodynamic cycle perturbation (TCP) method with explicit solvent. These errors were minimized or canceled, however, when relative hydration free energy differences (ΔΔGhyd) were calculated using a combination of ab initio quantum mechanical calculations and free energy perturbation methods. Calculated values for a variety of aldehydes and ketones were consistent with experimental data. © 1995 John Wiley & Sons, Inc. 相似文献
105.
A. Fahli J. P. Coffin G. Guillaume B. Heusch F. Jundt F. Rami P. Wagner P. Fintz A. J. Cole S. Kox Y. Schutz N. Cindro 《Zeitschrift für Physik A Hadrons and Nuclei》1987,326(2):169-177
The light charged particles emitted in the40Ar+68Zn reaction performed at 14.6, 19.6 and 35 MeV/nucleon have been studied inclusively. The energy spectra have been analysed in terms of preequilibrium emission, moving source and coalescence models. A complete coherence between the present data and those obtained separately from heavy fragment studies is achieved. These data are consistent with the onset of projectile fragmentation between 20 and 35 MeV/nucleon correlated with the formation of a highly excited region of the nuclear system inducing light particle emission. The other sources of light particles can be interpreted as statistical and sequential decay of the quasi projectile. 相似文献
106.
Valentina A. Ol’shevskaya Rami Ayuob Pavel V. Petrovskii Galina L. Levit Valery N. Charushin Valery N. Kalinin 《Journal of organometallic chemistry》2005,690(11):2761-2765
General method for preparation of high yields of novel N-protected carborane amino acid derivatives, 3-acylamino-1-carboxymethyl-2-R-o-carboranes (R = H, Me, Ph), is reported. The synthesis starts from readily available 3-amino-o-carboranes and includes the protection of amino group, introduction of carboxymethyl function to the carbon atom of polyhedron via the metallation of carborane CH bond with sodium amide in liquid ammonia, and treatment of corresponding sodium carboranes with sodium bromoacetate. Deprotection of N-acylated carborane amino acids is studied in acidic media. Depending on the procedure employed, closo- or nido-carborane amino acids were obtained. 相似文献
107.
Copolymers of ethyl acrylate (M1) and n-butyl methacrylate (M2) were prepared by benzoyl peroxide initiation in solution at 60° and copolymer compositions estimated by [13C]-NMR spectroscopy. The kinetic behaviour is approximately ideal with r1 = 1/r2 = 0.47. Relaxation times T1 were determined for six of the carbons in M2 units and one in the M1 units; they range from 0.07 to 1.65 sec. 相似文献
108.
Rami Grossberg Monica VanDieren Andrés Villaveces 《Mathematical Logic Quarterly》2016,62(4-5):367-382
We prove the following main theorem: Let be an abstract elementary class satisfying the joint embedding and the amalgamation properties with no maximal models of cardinality μ. Let μ be a cardinal above the the Löwenheim‐Skolem number of the class. If is μ‐Galois‐stable, has no μ‐Vaughtian Pairs, does not have long splitting chains, and satisfies locality of splitting, then any two ‐limits over M, for , are isomorphic over M. 相似文献
109.
Bairavarasu SR Edwards ME Sastry MD Kochary F Kommidi P Reddy BR Lianos D Aggarwal MD 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(4):1581-1587
We present electron paramagnetic resonance (EPR)--evidence of photomagnetism under the conditions of in situ green laser illumination (photo-EPR) in lead magnesium niobate-lead titanate, Pb(Mg,Nb)O3-PbTiO3 (PMN-PT), containing nanoparticles/wires of orthorhombic beta-PbO as identified by Raman spectroscopy. Photo-EPR studies of the sample containing beta-PbO, brownish red in color, have shown intense line at g=2.00, and its yield increased when produced in the presence of 7.5 kG external magnetic field suggesting the formation of magnetic polaron. This was identified as due to interaction between Fe3+, photoinduced Pb3+ and unpaired electron trapped at oxygen vacancies. The photoinduced growth and decay of magnetic polaron has shown a non-exponential behavior. Photoluminescence (PL) studies were conducted with excitation at 308 nm (XeCl laser) and also at 454.5, 488 and 514.5 nm using Ar+ laser. The excitation with 308 nm gave broad PL centered at 500 and 710 nm the latter being quite prominent in beta-PbO containing crystals, along with cooperative luminescence at 350 nm involving two emitting centers. The excitation with Ar+ laser lines, close to the electronic absorption in samples containing beta-PbO gave richer and sharp PL emission in red region from the constituents of the magnetic polaron and also intense anti-Stokes emission on excitation with 514.5 nm radiation. This appears to be due to phototransfer optically stimulated luminescence (PT-OSL) involving electron-hole recombination at photoinduced magnetic polaron site. 相似文献
110.
Thomas TD Kukk E Sankari R Fukuzawa H Prümper G Ueda K Püttner R Harries J Tamenori Y Tanaka T Hoshino M Tanaka H 《The Journal of chemical physics》2008,128(14):144311
The carbon 1s photoelectron spectrum of CF4 measured at photon energies from 330 to 1500 eV shows significant contributions from nonsymmetric vibrational modes. These increase linearly as the photon energy increases. The excitation of these modes, which is not predicted in the usual Franck-Condon point of view, arises from the recoil momentum imparted to the carbon atom in the ionization process. A theory is presented for quantitative prediction of the recoil effect; the predictions of this theory are in agreement to the measurements. The experiments also yield the vibrational frequencies of the symmetric and asymmetric stretching modes in core-ionized CF4, the change in CF bond length upon ionization, -0.61 pm, and the Lorentzian linewidth of the carbon 1s hole, 67 meV. 相似文献