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Arshad Sadiqa Khan Majid Hussain Iqtadar 《International Journal of Theoretical Physics》2021,60(9):3631-3650
International Journal of Theoretical Physics - The use of digital contents has increased tremendously in this modern era. In fact, people spend more time on internet than ever which urged the... 相似文献
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Kha KM Perveen S Ayattollahi SA Saba N Rashid A Firdous S Haider SM Ullah Z Rahat S Khan Z 《Natural product letters》2002,16(4):283-290
Three glycosides and a long chain alcohol were isolated from the bulbs of Polianthes tuberosa, these were identified as 3,29-dihydroxystigmast-5-ene-3-O-beta-D-galactopyranoside (1), ethyl beta-D-galactopyranoside (2), ethyl-alpha-D-galactopyranoside (3), and 1-tricosanol (4). The structures were determined by extensive spectroscopic and chemical methods. All four isolated compounds were screened for their cytotoxicity, antibacterial and antifungal activities, none of the compounds showed any significant activity. 相似文献
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Emir Valencia Inge Weiss Sadiqa Firdous Alan J. Freyer Maurice Shamma Alejandro Urzús Victor Fajardo 《Tetrahedron》1984,40(20):3957-3962
Three Chilean barberries, Mart. ex Schult., . Hook and [ulbar|B. Phil. (Berberidaceae), have yielded several new isoindolobenzazepine and protoberberine alkaloids. Novel isoindolobenzazepines are (±)-13-deoxychilenine (), pictonamine (), chileninone (), (±)-chileniimi () and (±)-palmanine (). Highly oxidized protoberberines of particular interest include (±)-O-methylprechilenine () and (±)-prepseudopalmanine (), together with 13-methoxy-8-oxyberberine (). Isoindolobenzazepine alkaloids arise biogenetically from the rearrangement of highly oxidized protoberberines. 相似文献
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The influence of indium doping on the capacitance variation with temperature and applied bias voltage of Ge2Sb2Te5 is investigated. The capacitance-voltage (C-V) measurements of In0.3Ge2Sb2Te5 and Ge2Sb2Te5 thin films were performed for a sweep of voltages from −20 to +20 V at different temperatures. The results show different capacitance behavior of In0.3Ge2Sb2Te5 and Ge2Sb2Te5 films. As the temperature increases the capacitance of the indium-doped sample decreases and becomes negative. The negative capacitance effect might be attributed to a significant increase of the film’s conductivity due to temperature and applied bias voltage. The nonlinearity in the capacitance and conductivity could be related to the nucleation mechanism as the temperature becomes close to the amorphous-crystalline transition temperature. 相似文献
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