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251.
A. M. El-Nagger F. S. M. Ahmed A. M. Abd El-Salam M. A. El-Gazzar 《Journal of heterocyclic chemistry》1982,19(5):1025-1028
The syntheses of different 9-(N-phthalyl- or N-tosyl- or free aminoacyl)carbazoles and the corresponding derivatives of 3,6-dinitrocarbazoles and some derivatives of 3,6-diamino-9-(N-phthalylaminoacyl)carbazoles (II-XXXII) are described. Compounds VIII, XIII-XVII and XXIII-XXVII were found to be active against a number of microorganisms. 相似文献
252.
253.
Y. M. Abd El-Aziz 《Journal of Thermal Analysis and Calorimetry》1997,50(5-6):873-878
The influence of the point defects introduced by means of Sm3+ on the thermal properties of LiKSO4 crystals was studied in the vicinity of the high-temperature phase at 708 and 940 K. The temperature dependence of the specific heat was found to vary monotonously with the Sm3+content, while the first transition temperature was unchanged. The change in the value of the specific heat was attributed to the correlation between the defect-defect interaction and the presence of internal local strain generated inside the crystal. The variation of the excess specific heat with the reduced temperature obeys the 3d Ising model. 相似文献
254.
F. M. Radwan A. M. Abd El-Hameed M. R. Mahmoud R. B. Fahim 《Journal of Thermal Analysis and Calorimetry》1987,32(3):883-891
The parent material, ammonium permanganate, was carefully decomposed in air at 120°. The product, referred to as the starting material (SM), was then subjected to thermal treatment in air for 5 hr in the temperature range 150–1200°. Chemical analysis of SM indicated that the main decomposition product of NH4MnO4 was Mn2O3, together with MnO2, NH4NO3, H2O and O2. Mn3O4 started to form at 900°. The infrared spectra of various calcination products revealed the retention of NH
4
+
in the lattice structure up to 300°, and reflected the presence of excess oxygen as coordinated O
2
–
. The TG, DTA and IRA results on SM supported the chemical analysis data. X-ray analysis was carried out for phase identification and to follow transformations and the formation of a solid solution between MnO2 and Mn2O3.
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal), 1986. 相似文献
Zusammenfassung Die Muttersubstanz, Aramoniumpermanganat, wurde in Luft bei 120° vorsichtig zersetzt. Das dabei erhaltene Ausgangsmaterial (SM) wurde danach in Luft 5 Stunden im Temperaturbereich von 150–1200° thermisch behandelt. Die chemische Analyse von SM ergab, daß als Hauptprodukt der Zersetzung von NH4MnO4, Mn2O3 auftritt neben MnO2, NH4NO3, H2O und O2. Die Bildung von Mn3O4 beginnt bei 900°. Aus Infrarotspektren verschiedener Kalzinierungsprodukte ist ersichtlich, daß in der Gitterstruktur NH 4 + bis 300° zurückgehalten wird und überschüssiger Sauerstoff in Form von koordiniertem O2 vorliegt. Die Ergebnisse der TG-, DTA- und IRA-Untersuchungen von SM bestätigen Daten der chemischen Analyse. Mittels Röntgenanalyse wurden die Phasen identifiziert und der Verlauf der Phasenübergänge und der Bildung einer festen Lösung zwischen MnO2 und Mn2O3 verfolgt.
120°. , , 5 150–1200°. , , , , . 900° Mn3O4. 300° - O 2 – . , . , .
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal), 1986. 相似文献
255.
Summary The use of Omega Chrome Black PPV for the EDTA titration of zinc, manganese, nickel, cadmium, magnesium and lead is described. The sensitivity limits of detection of the equivalence points are determined. The indicator has been found to be suitable in titrations of mixtures of manganese and zinc. 相似文献
256.
Hazim M. Ali Mohammed Gamal Mohammed M. Ghoneim Lobna Mohammed Abd Elhalim 《Molecules (Basel, Switzerland)》2022,27(3)
Combination therapy of many anthelmintic drugs has been used to achieve fast animal curing. Q-DRENCH is an oral suspension, containing four different active drugs against GIT worms in sheep, commonly used in Australia and New Zeeland. The anti-parasitic drugs are Albendazole (ALB), Levamisole HCl (LEV), Abamectin (ABA), and Closantel (CLO). The main purpose of this study is to present a new simultaneous stability-indicting HPLC-DAD method for the analysis of the four drugs. The recommended liquid system was 1 mL of Triethylamine/L water, adjusting the pH to 3.5 by glacial acetic acid: acetonitrile solvent (20:80, v/v). Isocratic elusion achieved the desired results of separation at a 2 mL/min flow rate using Zorbax C-18 as a stationary phase. Detection was performed at 210 nm. The linearity ranges were 15.15 to 93.75 μg/mL for ALB, 25 to 150 μg/mL for LEV, 30 to 150 μg/mL for ABA, and 11.7 to 140.63 μg/mL for CLO. Moreover, the final greenness score was 0.62 using the AGREE tool, which reflects the eco-friendly nature. Moreover, the four drugs were determined successfully in the presence of their stressful degradation products. This work presents the first chromatographic method for simultaneous analysis for Q-DRENCH oral suspension drugs in the presence of their stressful degradation products. 相似文献
257.
Kian-Kai Cheng Muhammad Helmi Nadri Nor Zalina Othman Siti Nor Azlina Abd Rashid Ying-Chin Lim Hong-Yeng Leong 《Molecules (Basel, Switzerland)》2022,27(11)
Michelia × alba (M. alba) is a flowering tree best known for its essential oil, which has long been used as a fragrance ingredient for perfume and cosmetics. In addition, the plant has been used in traditional medicine in Asia and dates back hundreds of years. To date, there is a limited number of publications on the bioactivities of M. alba, which focused on its tyrosinase inhibition, antimicrobial, antidiabetic, anti-inflammatory, and antioxidant activities. Nevertheless, M. alba may have additional unexplored bioactivities associated with its bioactive compounds such as linalool (72.8% in flower oil and 80.1% in leaf oil), α-terpineol (6.04% flower oil), phenylethyl alcohol (2.58% flower oil), β-pinene (2.39% flower oil), and geraniol (1.23% flower oil). Notably, these compounds have previously been reported to exhibit therapeutic activities such as anti-cancer, anti-inflammation, anti-depression, anti-ulcer, anti-hypertriglyceridemia, and anti-hypertensive activities. In this review paper, we examine and discuss the scientific evidence on the phytochemistry, bioactivities, and traditional uses of M. alba. Here, we report a total of 168 M. alba biological compounds and highlight the therapeutic potential of its key bioactive compounds. This review may provide insights into the therapeutic potential of M. alba and its biologically active components for the prevention and treatment of diseases and management of human health and wellness. 相似文献
258.
Eman Soliman Mohamed M. Ibrahim Mohamed E. El-Khouly Ibrahim El-Mehasseb Abd El-Motaleb M. Ramadan Magdy E. Mahfouz Shaban Y. Shaban Rudi van Eldik 《Molecules (Basel, Switzerland)》2022,27(11)
Two zinc(II) complexes, DBZ and DBZH4, that have (ZnN3S2) cores and differ in the bridging mode of the ligating backbone, effectively bind to BSA. The binding affinity varies as DBZ > DBZH4 and depends on the ligand structure. At low concentrations, both complexes exhibit dynamic quenching, whereas at higher concentrations they exhibit mixed (static and dynamic) quenching. The energy transfer mechanism from the BSA singlet excited state to DBZ and DBZH4, is highly likely according to steady-state fluorescence and time-correlated singlet photon counting. Molecular docking was used to support the mode of interaction of the complexes with BSA and showed that DBZ had more energy for binding. Furthermore, antibacterial testing revealed that both complexes were active but to a lesser extent than chloramphenicol. In comparison to DBZH4, DBZ has higher antibacterial activity, which is consistent with the binding constants, molecular docking, and particle size of adducts. These findings may have an impact on biomedicine. 相似文献
259.
Ragaa A. Hamouda Amera Abd El Latif Ebtihal M. Elkaw Amenah S. Alotaibi Asma Massad Alenzi Hanafy A. Hamza 《Molecules (Basel, Switzerland)》2022,27(5)
There is a very vital antioxidant extracted from microgreen alga. Chlorella vulgaris has major advantages and requires high yield worldwide. Some microalgae require vitamins for their growth promotion. This study was held to determine the impact of different vitamins including Thiamine (B1), Riboflavin (B2), Pyridoxine (B6), and Ascorbic acid (c) at concentrations of 0.02, 0.04, 0.06, and 0.08 mg/L of each. Each vitamin was added to the BG11 growth medium to determine the effect on growth, total carbohydrate, total protein, pigments content, antioxidant activities of Chlorella vulgaris. Moreover, antitumor effects of methanol extract of C. vulgaris without and with the supplement of thiamine against Human prostate cancer (PC-3), Hepatocellular carcinoma (HEPG-2), Colorectal carcinoma (HCT-116) and Epitheliod Carcinoma (Hela) was estimated in vitro. C. vulgaris supplemented with various vitamins showed a significant increase in biomass, pigment content, total protein, and total carbohydrates in comparison to the control. Thiamine was the best vitamin influencing as an antioxidant. C. vulgaris supplemented with thiamine had high antitumor effects in vitro. So, it’s necessary to add vitamins to BG11 media for enhancement of the growth and metabolites. 相似文献
260.
Shakeel Ahmad Khandy Ishtihadah Islam Kulwinder Kaur Atif Mossad Ali Alaa F. Abd El-Rehim 《Molecules (Basel, Switzerland)》2022,27(12)
This paper presents the strain effects on the structural, electronic and phonon properties of a newly proposed SrBaSn half Heusler compound. Since it is stable considering chemical thermodynamics, we tested its strength against uniform strain w.r.t phonon spectrum and it produces a direct bandgap of 0.7 eV. The direct bandgap reduces to 0.19 eV at −12% strain beyond which the structure is unstable. However, an indirect gap of 0.63 eV to 0.39 eV is observed in the range of +5% to +8% strain and afterwards the strain application destabilizes the structure. From elastic parameters, the ductile nature of this material is observed. 相似文献