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81.
Zubair Ahmad Mahdi Hasan Suhail Issam Ibrahim Muhammad Wissam Khayer Al-Rawi Khaulah Sulaiman Qayyum Zafar Ahmad Sazali Hamzah Zurina Shaameri 《中国物理 B》2013,(10):192-196
In this paper, we present the effect of varied illumination levels on the electrical properties of the organic blend bulk heterojuction (BHJ) photodiode. To prepare the BHJ blend, poly(2-methoxy-5(2P-ethylhexyloxy) phenyleneviny- lene (MEH-PPV) and aluminum-tris-(8-hydroxyquinoline) (Alq3) are used as donor and acceptor materials, respectively. In order to fabricate the photodiode, a 40-nm thick film of poly(3, 4-ethylendioxytbiophene):poly(styrensulfonate) (PE- DOT:PSS) is primarily deposited on a cleaned ITO coated glass substrate by spin coating technique. The organic photo- sensitive blend is later spun coated on the PEDOT:PSS layer, followed by the lithium fluoride (LiF) and aluminium (A1) thin films deposition by thermal evaporation. The optical properties of the MEH-PPV:Alq3 blend thin films are investigated using photoluminescence (PL) and UV-Vis spectroscopy. The photodiode shows good photo-current response as a function of variable illumination levels. The responsivity value - 8 mA/W at 3 V is found and the ratio of photo-current to dark current (lph/IDark) is found to be 1.24. 相似文献
82.
83.
Background
Sonchus asper (SA) is traditionally used for the treatment of various ailments associated with liver, lungs and kidneys. This study was aimed to investigate the therapeutic potential of nonpolar (hexane, SAHE; ethyl acetate, SAEE and chloroform, SACE) and polar (methanol, SAME) crude extracts of the whole plant. 相似文献84.
S. K. Durrani A. H. Qureshi S. Qayyum M. Arif 《Journal of Thermal Analysis and Calorimetry》2009,95(1):87-91
The effects of barium substitution for Bi or Sr sites on the growth of superconducting phases have been studied. The sol spray
process has been used to synthesis the Bi-Sr-Ca-Cu-O (BSCCO) and Ba-BSCCO homogeneous ceramic powders. Thermogravimetric (TG),
differential thermal analysis (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) techniques were employed
to characterize the synthesized materials. The electrical resistance was measured by classical d.c. fourprobe technique. It
has been observed that sol spray process has affected the physico-chemical properties of the materials and also avoid the
use of chelating agent as in the case of sol gel process. In addition to the Bi2Sr2CaCu2O8 (2212) phase Ba doped specimens also contained Bi2Sr2Ca2Cu3O10 (2223), BaBiO3, BaCuO2 and CuO phases.
The results revealed that the specific effect of barium-doping on either sites (Bi or Sr) seems to avoid the formation of
higher volume fraction of the low T
c phase and promoting the formation of BiBaO3, BaCuO2 and CuO along with formation of a high T
c 2223 phase. The substitution of Ba on either sites (Bi or Sr) lower the sintering temperature for the formation of high T
c (small volume fraction) however, the Ba doped specimens also contained non-superconducting phases. 相似文献
85.
Kulsoom Zahara Yamin Bibi Saadia Masood Sobia Nisa Abdul Qayyum Muhammad Ishaque Khurram Shahzad Waseem Ahmed Zahid Hussain Shah Hameed Alsamadany Seung-Hwan Yang Gyuhwa Chung 《Molecules (Basel, Switzerland)》2021,26(19)
Gui Zhen Cao is an herbal formulation that has been documented in Chinese traditional medicine as a remedy for diarrhea, dysentery, inflammation, and toxicity. The sources of this formulation (Bidens pilosa L., Bidens biternata (Lour.) Merr. & Sherff, Bidens bipinnata L.) are also listed in ethnomedicinal reports all over the world. In this study, all these plants are tested for in vitro anticandida activity. A quantitative evaluation of the phytochemicals in all these plants indicated that their vegetative parts are rich in tannins, saponins, oxalates, cyanogenic glycoside and lipids; moreover, the roots have high percentages of alkaloids, flavonoids, and phenols. The results indicated significant anticandida activity, especially for the hexane extract of B. bipinnata leaves which inhibited C. albicans (42.54%), C. glabrata (46.98%), C. tropicalis (50.89%), C. krusei (40.56%), and C. orthopsilosis (50.24%). The extract was subjected to silica gel chromatography and 220 fractions were obtained. Purification by High Performance Liquid Chromatography with Diode-Array Detection (HPLC–DAD) and Gas Chromatography tandem Mass Spectrometry (GC-MS/MS) analysis led to the identification of two anticandida compounds: dehydroabietic and linoleic acid having an inhibition of 85 and 92%, respectively. 相似文献