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61.
Hany M. Abd El-Lateef Mai M. Khalaf Alaa El-dien Al-Fengary Mahmoud Elrouby 《Molecules (Basel, Switzerland)》2022,27(8)
Drinking water containing nitrate ions at a higher concentration level of more than 10 mg/L, according to the World Health Organization (WHO), poses a considerable peril to humans. This danger lies in its reduction of nitrite ions. These ions cause methemoglobinemia during the oxidation of hemoglobin into methemoglobin. Many protocols can be applied to the remediation of nitrate ions from hydra solutions such as Zn metal and amino sulfonic acid. Furthermore, the electrochemical process is a potent protocol that is useful for this purpose. Designing varying parameters, such as the type of cathodic electrode (Sn, Al, Fe, Cu), the type of electrolyte, and its concentration, temperature, pH, and current density, can give the best conditions to eliminate the nitrate as a pollutant. Moreover, the use of accessible, functional, and inexpensive adsorbents such as granular ferric hydroxide, modified zeolite, rice chaff, chitosan, perlite, red mud, and activated carbon are considered a possible approach for nitrate removal. Additionally, biological denitrification is considered one of the most promising methodologies attributable to its outstanding performance. Among these powerful methods and materials exist zero-valent iron (ZVI), which is used effectively in the deletion process of nitrate ions. Non-precious synthesis pathways are utilized to reduce the Fe2+ or Fe3+ ions by borohydride to obtain ZVI. The structural and morphological characteristics of ZVI are elucidated using UV–Vis spectroscopy, zeta potential, XRD, FE-SEM, and TEM. The adsorptive properties are estimated through batch experiments, which are achieved to control the feasibility of ZVI as an adsorbent under the effects of Fe0 dose, concentration of NO3− ions, and pH. The obtained literature findings recommend that ZVI is an appropriate applicant adsorbent for the remediation of nitrate ions. 相似文献
62.
Alan R. Kennedy Abedawn I. Khalaf Colin J. Suckling 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e265-e266
The title compound, C10H10O5, was found to exist as the endo–cis isomer with a pair of enantiomers in the asymmetric unit. The cyclohexene ring is folded about the methylene‐to‐CH(acetoxy) vector to give a boat conformation. 相似文献
63.
Violeta Jevtovi Haneen Hamoud Salma Al-Zahrani Khalaf Alenezi Salman Latif Tahani Alanazi Fahad Abdulaziz Duan Dimi 《Molecules (Basel, Switzerland)》2022,27(15)
New complex Co(III) with ligand Pyridoxal-S-methyl-isothiosemicarbazone, (PLITSC) was synthesized. X-ray analysis showed the bis-ligand octahedral structure of the cobalt complex [Co(PLITSC-H)2]BrNO3·CH3OH (compound 1). The intermolecular interactions governing the crystal structure were described by the Hirsfeld surface analysis. The structure of compound 1 and the corresponding Zn complex (([Zn(PLTSC)(H2O)2]SO4·H2O)) were optimized at the B3LYP/6–31 + G (d,p)/LanL2DZ level of theory, and the applicability was assessed by comparison with the crystallographic structure. The natural bond orbital analysis was used for the discussion on the stability of formed compounds. The antibacterial activity of obtained complexes towards S. aureus and E. coli was determined, along with the effect of compound 1 on the formation of free radical species. Activity of compound 1 towards the removal of methylene blue was also investigated. The voltammograms of these compounds showed the reduction of metal ions, as well as the catalyzed reduction of CO2 in acidic media. 相似文献
64.
Anas D. Khalaf Tareq Saeed Reman Abu-Shanab Waleed Almutiry Mahmoud Abouagwa 《Entropy (Basel, Switzerland)》2022,24(5)
This study deals with drift parameters estimation problems in the sub-fractional Vasicek process given by , with , being unknown and ; here, represents a sub-fractional Brownian motion (sfBm). We introduce new estimators for and for based on discrete time observations and use techniques from Nordin–Peccati analysis. For the proposed estimators and , strong consistency and the asymptotic normality were established by employing the properties of . Moreover, we provide numerical simulations for sfBm and related Vasicek-type process with different values of the Hurst index H. 相似文献
65.
Dhanasekaran S SatheeshKumar Palanisamy Fahima Hajjej Osamah Ibrahim Khalaf Ghaida Muttashar Abdulsahib Ramalingam S 《Entropy (Basel, Switzerland)》2022,24(11)
Multiple-input Multiple-Output (MIMO) systems require orthogonal frequency division multiplexing to operate efficiently in multipath communication (OFDM). Channel estimation (C.E.) is used in channel conditions where time-varying features are required. The existing channel estimation techniques are highly complicated. A channel estimation algorithm is needed to estimate the received signal’s correctness. In order to resolve this complexity in C.E. methodologies, this paper developed an Improved Channel Estimation Algorithm integrated with DFT-LS-WIENER (ICEA-DA). The Least Square (L.S.) and Minimum Mean Square Error (MMSE) algorithms also use the Discrete Fourier Transform (DFT)-based channel estimation method. The DFT-LS-WIENER channel estimation approach is recommended for better BER performance. The input signal is modulated in the transmitter module using the Quadrature Phase Shift Keying (QPSK) technique, pulse modeling, and least squares concepts. The L.S. Estimation technique needs the channel consistent throughout the estimation period. DFT joined with L.S. gives higher estimation precision and limits M.S.E. and BER. Experimental analysis of the proposed state-of-the-art method shows that DFT-LS-WIENER provides superior performance in terms of symbol error rate (S.E.R.), bit error rate (BER), channel capacity (CC), and peak signal-to-noise (PSNR). At 15 dB SNR, the proposed DFT-LS-WIENER techniques reduce the BER of 48.19%, 38.19%, 14.8%, and 14.03% compared to L.S., LS-DFT, MMSE, and MMSE-DFT. Compared to the conventional algorithm, the proposed DFT-LS-WIENER outperform them. 相似文献
66.
67.
Wang Zhen Khalaf Abdul Jalil M. Tian Huaigu Alsaedi Ahmed Hayat Tasawar 《The European physical journal. Special topics》2020,229(6-7):1109-1116
The European Physical Journal Special Topics - Although chaotic flows with special properties in their equilibria have been investigated widely, such an effort about chaotic maps has been... 相似文献
68.
In this work, we have probed the structural, electronic, and magnetic properties of the (111) surface of rocksalt (RS) VPo. The first-principles full-potential linearized augmented plane-wave method is used. Bulk VPo is found to be a half-metallic ferromagnet at equilibrium lattice constant (0.59 nm) with a total spin magnetic moment of 3.0 μB per formula unit. At the same equilibrium lattice constant, the V-terminated (111) surface preserves the half-metallic characteristics of the bulk VPo, however, the surface states destroy the gap in the minority spin band of the Po-terminated (111) surface. We also discuss the surface stability. 相似文献
69.
70.