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71.
Krzysztof Kozak Jadwiga Mazur Janja Vaupotič Dominik Grządziel Ivan Kobal Khaled M.H. Omran 《Isotopes in environmental and health studies》2013,49(2):274-282
Natural radioactivity is one of the essential components of the environment. Unlike the Sudety mountains area in Poland, the Tatra Mountains were not the subject of wide survey as regards the levels of natural radioactivity. Especially, the concentrations of radon (natural radioactive gas) have not been investigated there in terms of their possible negative health impact. Within the frame of bilateral cooperation between the Institute of Nuclear Physics in Kraków, Poland, and the Jo?ef Stefan Institute in Ljubljana, Slovenia, the measurements of natural radioactive elements in old uranium mines in the Tatra National Park were performed in June 2010. The investigated sites were located in Dolina Bia?ego (The Valley of the White). One of the mines is situated near the tourist path. The paper presents the results of complex measurements of natural radioactivity in both uranium drifts. The concentration of radon gas inside the mining drifts exceeded 28,000 Bq m?3. Also, very high gamma dose rates were observed (up to 5600 nSv h?1). The maximum concentrations of natural radioactive elements (potassium 40K, radium 226Ra, thorium 232Th) in rock samples amounted to 535, 2137, and 18 Bq kg?1, respectively. The effective dose rates due to radon and thoron inhalation have been assessed as 0.013 mSv h?1 (for the lowest concentration) and 0.121 mSv h?1 (for the highest concentration). 相似文献
72.
73.
A novel series of (Z)‐1‐(arylhydrazono)‐1‐(benzothiazol‐2′‐ylthio)propan‐2‐ones have been prepared and their utility as building blocks in the synthesis of novel derivatives of Pyridazin‐6(1H)‐ones, pyridazin‐6(1H)‐imines, and phthalazine incorporating a benzothiazole residue are investigated. All of the title compounds were confirmed by elemental analysis, IR, 1H NMR, 13C NMR, NOE, and mass spectrometry. The synthesized compounds are screened for their antibacterial as well as antifungal activity. All the tested compounds showed high to moderate activity against the selected microorganisms. J. Heterocyclic Chem., (2011). 相似文献
74.
Nejatbakhsh S. Anagri A. Valinataj Omran A. Pulpytel J. Bazin C. Ullah M. Mirshahi M. Rezaie H. Javadpour J. Arefi-Khonsari F. 《Plasma Chemistry and Plasma Processing》2021,41(1):245-264
Plasma Chemistry and Plasma Processing - In this research work we demonstrated that a helium/oxygen Dielectric Barrier Discharge conferred hydrophilic functional groups onto the surface, which lead... 相似文献
75.
Hayat Ullah Shoaib Khan Fazal Rahim Muhammad Taha Rashid Iqbal Maliha Sarfraz Syed Adnan Ali Shah Muhammad Sajid Mohamed F. Awad Awatif Omran Marzough Aziz Albalawi Mahmoud A. Abdelaziz Azza Al Areefy Ibrahim Jafri 《Molecules (Basel, Switzerland)》2022,27(20)
Diabetes mellitus is one of the most chronic metabolic diseases. In the past few years, our research group has synthesized and evaluated libraries of heterocyclic analogs against α-glucosidase and α-amylase enzymes and found encouraging results. The current study comprises the evaluation of benzimidazole-bearing thiosemicarbazone as antidiabetic agents. A library of fifteen derivatives (7–21) was synthesized, characterized via different spectroscopic techniques such as HREI-MS, NMR, and screened against α-glucosidase and α-amylase enzymes. All derivatives exhibited excellent to good biological inhibitory potentials. Derivatives 19 (IC50 = 1.30 ± 0.20 µM and 1.20 ± 0.20 µM) and 20 (IC50 = 1.60 ± 0.20 µM and 1.10 ± 0.01 µM) were found to be the most potent among the series when compared with standard drug acarbose (IC50 = 11.29 ± 0.07 and 11.12 ± 0.15 µM, respectively). These derivatives may potentially serve as the lead candidates for the development of new therapeutic representatives. The structure–activity relationship was carried out for all molecules which are mainly based upon the pattern of substituent/s on phenyl rings. Moreover, in silico docking studies were carried out to investigate the active binding mode of selected derivatives with the target enzymes. 相似文献
76.
O. A. Omran H. M. Moustafa 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2519-2528
A number of spiro[cyclopentane (cyclohexane, and cycloheptane)-1,4′-perhydro-[1,3,2]diazaphosphole] derivatives (3a–c, 5a–c, 11a–c, and 12a–c) and spiro-[cyclopentane (cyclohexane, and cycloheptane)-1,4′-perhydro[1,3,2]oxaazaphos-phole] derivatives (7a–c) were prepared via an interaction of 2,4-bis-(4-methoxy-phenyl)-1,3,2,4-dithiaphosphetane-2,4-disulphide (1) with substances containing two functional groups. 相似文献
77.
A. Tataroğlu Ahmed A. Al-Ghamdi Saad Bin Omran W. A. Farooq Farid El-Tantawy F. Yakuphanoglu 《Journal of Sol-Gel Science and Technology》2014,71(3):421-427
A new Schottky diode (InFe2O4/p-Si/Al) was fabricated using the sol–gel spin coating technique. The current–voltage (I–V) characteristics of the Schottky diode were investigated under various illumination intensities. The value of ideality factor (n) and zero-bias barrier height (ΦB0) for all illuminations was determined by using the forward-bias I–V measurements, and were found to be about 4.20 and 0.72 eV, respectively. The reverse current of the diode in the reverse bias increases with the increasing illumination intensities. Also, the photocurrent under illumination is higher than the dark current. In addition, the capacitance–voltage (C–V) and conductance–voltage (G–V) measurements of the diode were studied in the frequency range of 10 kHz–1 MHz. The measured values of the C decrease with the increasing frequency. The decrease in capacitance was explained on the basis of interface states. To obtain the real C and G of the diode, the measured values of C and G were corrected to eliminate the effect of series resistance. The obtained results suggest that the diode can be used as a photodiode in optoelectronic applications. 相似文献
78.
N,N′‐Diphenylpiperidine‐1‐carbohydrazonamide 1 was prepared and treated with halo compounds, active nitriles, diethylhy malonate, ketones, CS2, phenylisocyanate, phenylisothiocyanate, LR, ethyl 2‐cyano‐3,13‐dithiomethylacetate, and benzylidenenitriles to give the corresponding triazines 2–4, pyrazoles 5 and 6, triazoles 7, 8, and 10, triazaphosphole 11, and triazepines 12 – 14, respectively. 相似文献
79.
Ayman M. Atta Manar E. Abdel-Rauf Nermine E. Maysour Amani K. Gafer 《Journal of Dispersion Science and Technology》2013,34(5):583-595
Water-soluble surfactants based on rosin acids were synthesized from condensed rosin acid-formaldehyde. This was completed by esterification of series of rosin acid formaldehyde resins with poly(ethylene glycol) having different molecular weights to produce series of rosin esters. The structure of the produced resins was determined by infrared and 1HNMR analysis. The molecular weight of the produced surfactants was determined by gel permeation chromatography (GPC) technique. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration (CMC), and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (Amin), and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process were calculated and are discussed. The dispersion efficiency of the prepared surfactants as petroleum oil spill dispersants was determined and correlated with the surface activity, concentrations of the prepared surfactants and type of petroleum crude oil. 相似文献