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541.
Yulian Gao Boshra Mahmoudi Ali Fakhri Hamed Aghazadeh Mojgan Hosseini Hossein Ali Ebrahimi 《应用有机金属化学》2019,33(8)
A MnO2/CdTiO3 is prepared by a simple chemical method. The organic compound such as antibiotics is a contaminant found in large amounts in pharmaceutical industrial wastewater. Pharmaceutical compounds are toxic. The nano‐product was characterized by SEM, XRD, XPS, DLS and UV–vis DRS revealed that the MnO2 nanoparticles were supported on the CdTiO3 surface. The crystallite size was found as 72.11 nm, and 38.13 nm for CdTiO3, and MnCdTi‐1 nanocomposites, respectively. The prepared catalyst was used for photo‐degradation of cephalexin under UV light irradiation. The result implies the complete degradation of cephalexin was carried out at 80 min for MnCdTi‐2 nanocomposites (88.88%) due to this catalyst has the lowest band gap compared to the other catalyst. The MnO2/CdTiO3 was selected for fungicidal and bactericidal efficiency against Aspergillus flavus, and candida albicans and Escherichia coli, and Staphylococcus aureus. The MnO2/CdTiO3–2 has great activity is compared with the other MnO2/CdTiO3–0 and MnO2/CdTiO3–1 samples. 相似文献
542.
Moazami Hamid Reza Hosseiny Davarani Saied Saeed Ghassemi Nasrin Hamed Sara 《Journal of Solid State Electrochemistry》2020,24(5):1231-1238
Journal of Solid State Electrochemistry - The present work describes a facile route for the synthesis of CdMn2O4 nanoplates. The nanoplates were synthesized by cathodic electrogeneration of base... 相似文献
543.
544.
Ezzat A. Hamed 《国际化学动力学杂志》1997,29(8):599-605
The kinetics of the reactions of 2-chloro-3-nitropyridine (ortho-like) and 5-nitro (para-like) isomer with morpholine and piperidine were studied in methanol and benzene at several amine concentrations and temperatures in the range 25–45°C. The data show that k/k ratios are less than unity in methanol. The steric hindrance in the transition state of the 3-nitro (ortho-like) isomer retards o-substitution while the stability of p-quinonoid structure of the 5-nitro (para-like) isomer favors p-substitution. In benzene, the k3-NO2/k5-NO2 ratios are greater than unity. The hydrogen bonding formation between the ammonium hydrogen and the ortho-nitro group in the transition state of 3-nitro isomer favors the o-substitution. © 1997 John Wiley & Sons, Inc. 相似文献
545.
Shafie Arefeh Mohammadi-Khanaposhtani Maryam Asadi Mehdi Rahimi Nastaran Ranjbar Parviz Rashidi Ghasemi Jahan B. Larijani Bagher Mahdavi Mohammad Shafaroodi Hamed Dehpour Ahmad Reza 《Molecular diversity》2020,24(1):179-189
Molecular Diversity - A novel series of 1,2,3-triazolo-benzodiazepine derivatives 6a–o has been synthesized and evaluated in vivo for their anticonvulsant activities using by... 相似文献
546.
Manal Y. Sameeh Manal M. Khowdiary Hisham S. Nassar Mahmoud M. Abdelall Hamada H. Amer Abdelaaty Hamed Ahmed A. Elhenawy 《Molecules (Basel, Switzerland)》2022,27(3)
This work aimed to synthesize a new antihyperglycemic thiazolidinedione based on the spectral data. The DFT\B3LYP\6-311G** level of theory was used to investigate the frontier molecular orbitals (FMOs), chemical reactivity and map the molecular electrostatic potentials (MEPs) to explain how the synthesized compounds interacted with the receptor. The molecular docking simulations into the active sites of PPAR-γ and α-amylase were performed. The in vitro potency of these compounds via α-amylase and radical scavenging were evaluated. The data revealed that compounds (4–6) have higher potency than the reference drugs. The anti-diabetic and anti-hyperlipidemic activities for thiazolidine-2,4-dione have been investigated in vivo using the alloxan-induced diabetic rat model along with the 30 days of treatment protocol. The investigated compounds didn’t show obvious reduction of blood glucose during pre-treatments compared to diabetic control, while after 30 days of treatments, the blood glucose level was lower than that of the diabetic control. Compounds (4–7) were able to regulate hyperlipidemia levels (cholesterol, triglyceride, high-density lipoproteins and low- and very-low-density lipoproteins) to nearly normal value at the 30th day. 相似文献
547.
548.
Mostafa Rostaghi Mohammad Mahdi Khatibi Mohammad Reza Ashory Hamed Azami 《Entropy (Basel, Switzerland)》2021,23(11)
Bearing vibration signals typically have nonlinear components due to their interaction and coupling effects, friction, damping, and nonlinear stiffness. Bearing faults affect the signal complexity at various scales. Hence, measuring signal complexity at different scales is helpful to diagnosis of bearing faults. Numerous studies have investigated multiscale algorithms; nevertheless, multiscale algorithms using the first moment lose important complexity data. Accordingly, generalized multiscale algorithms have been recently introduced. The present research examined the use of refined composite generalized multiscale dispersion entropy (RCGMDispEn) based on the second moment (variance) and third moment (skewness) along with refined composite multiscale dispersion entropy (RCMDispEn) in bearing fault diagnosis. Moreover, multiclass FCM-ANFIS, which is a combination of adaptive network-based fuzzy inference systems (ANFIS), was developed to improve the efficiency of rotating machinery fault classification. According to the results, it is recommended that generalized multiscale algorithms based on variance and skewness be examined for diagnosis, along with multiscale algorithms, and be used to achieve an improvement in the results. The simultaneous usage of the multiscale algorithm and generalized multiscale algorithms improved the results in all three real datasets used in this study. 相似文献
549.
Majid Nazeri Abdollah Eslami Majd Reza Massudi Seyed Hassan Tavassoli Alimohammad Mesbahinia Hamed Abbasi 《Journal of Russian Laser Research》2016,37(2):164-171
We present a simple setup for laser-induced breakdown spectroscopy using the spatially resolved technique (SRLIBS). We show that, without any need for time-gated ICCD and pulse generator, the signal-to-background ratio is enhanced. We develop a homemade spectrograph with a movable slit located at its entrance to detect different parts of the plasma emission. For optimizing the position of the slit, we use the shadowgraphy technique to study the plasma expansion. In this low cost setup, with nanosecond laser pulses, we perform SRLIBS experiments on the plasma induced in air and iron. Our results show that the signal-to-background ratio for iron and air is enhanced up to 15 and 8 times, respectively. 相似文献
550.
Talie Zarei Shahriar Mirpour Hamed Nikmaram Mahmood Ghoranneviss Sahar Mirpour Davoud Dorranian 《Plasma Chemistry and Plasma Processing》2017,37(1):99-114
Effects of high frequency spark plasma discharge as a time efficiency method in order to softening the natural hard water has been investigated experimentally. A very hard water sample with 331 ± 19 mg/l of CaCO3 hardness was used. The current and voltage of each spike was about 9.6 A and 3.5 kV respectively at 16 kHz frequency with 35 μs pulse width. Hard water was treated for 2, 4, 6, and 8 min. The concentration of CaCO3, Ca2+ ions, Mg2+ ions and pH as well as water conductivity was controlled before and after treatment. The concentration of CaCO3 dropped by 70%, after 8 min treatment. During the treatment, the pH had a fluctuation about 1.5 and finally remained in neutral state. Also the elemental composition, crystalline structure and morphology of the precipitates were identified. Molecular dynamics simulation revealed that the ozone and hydroxyl play important roles in the softening of the hard water. 相似文献