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71.
Mokashi Imran Khan Sher Afghan Abdullah Nur Azam Bin Azami Muhammad Hanafi Afzal Asif 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2555-2571
Journal of Thermal Analysis and Calorimetry - The use of Li-ion battery in electric vehicles is becoming extensive in the modern-day world owing to their high energy density and longer life. But... 相似文献
72.
A. Wadeasa S. L. Beegum S. Raja O. Nur M. Willander 《Applied Physics A: Materials Science & Processing》2009,95(3):807-812
We report a demonstration of heterojunction light emitting diode (LED) based on a hybrid n-ZnO-nanorod/p-polymer layered structure.
The ZnO was grown using the aqueous chemical growth (ACG) on top of the polymer(s) which were deposited on glass. The current–voltage
(I–V) behavior of the heterojunctions showed good rectifying diode characteristics. Room-temperature electroluminescence (EL)
spectra of the LEDs provided a broad emission band over a wide LED color range (430–650 nm), in which both zinc and oxygen
vacancy peaks are clearly detected. We present here luminescent devices based on the use of ZnO-nanorods in combination with
two different blended and multi-layered p-type polymers. Electroluminescence of the first batch of devices showed that white
bluish strong emission for the presently used polymers is clearly observed. We obtained a turn-on voltage of 3 V and break-down
voltage equal to −6 V for PVK-TFB blended device. The corresponding values for the NPD-PFO multilayer device were 4 V and
−14 V, respectively. The rectification factors were equal to 3 and 10 for the two devices, respectively. The films and devices
processed were characterized by scanning electron microscopy (SEM), DEKTAK 3ST Surface Profile, Semiconductor Parameter Analyzer,
photoluminescence (PL), and electroluminescence (EL). 相似文献
73.
Alraqa Shaya Y. Kaya Esra Nur Taşci Neşe Erbahar Dogan Durmuş Mahmut 《Journal of fluorescence》2022,32(5):1801-1813
Journal of Fluorescence - In this current study, the novel bis[4,5-(pyrene-2-yl)-3,6-(hexyloxy)] phthalonitrile (SPN) fluorophore has been successfully synthesized. Structural characterization of... 相似文献
74.
Gamze G
GER Ümmühan TÜRKYOLU Ezgi Nur GÜREN Süleyman YUR Abdullah Burak KARADUMAN Fatih G
GER Mehmet TEKN Gülmira
ZEK 《Turkish Journal of Chemistry》2021,45(2):387
In the present work, essential oil and fatty acids and extracts obtained from aerial parts of Phlomis linearis Boiss. & Bal. were investigated for chemical composition and biological activities. The phytochemical analyses were conducted with gas chromatography-mass spectrometry/flame ionisation detector (GC-MS/FID) and liquid chromatography-mass spectromtetry (LC-MS/MS) techniques. The extracts and essential oil were studied for α-amylase and acetylcholinesterase activities with two different spectrophotometric methods. Antimicrobial activities of the extracts were investigated by microdilution. The extracts were evaluated in vitro for cytotoxic effects against cancer and normal cell lines by MTT assay. The essential oil (EO) contained α-pinene (12.5%) and β-caryophyllene (10.7%) as main compounds. Palmitic (26.5%) and nonadecanoic acids (26.6%) were determined as fatty acids. Phytochemical analysis of the extracts found phenolic acids, phlinosides, verbascoside, and flavonoids. The extracts and essential oil demonstrated poor α-amylase inhibitory activity. The best acetylcholinesterase inhibitory activity was obtained for diethly ether extract of P. linearis (67.2 ± 3.4%) at 10 mg /mL concentration. Ethyl acetate extract found to be effective against Staphlococcus aureus at a minimum inhibitory concentration (MIC) of 156.26 µg/mL. Diethyl ether extract of P. linearis was active on A549 cell lines with an IC50 = 316 ± 4.16 µg/mL when compared with cisplatin IC50 = 24.43 ± 0.14 µg/mL. To the best of our knowledge, the present work is the first comprehensive report on anti-acetylcholinesterase, anti-α-amylase, and antimicrobial activities, as well as cytotoxic effects of P. linearis. 相似文献
75.
76.
Discharge current distributions generated underwater by spark discharges from the atmosphere to free water surfaces with conductivities in the range 0.07–10.0 S/m were investigated using a laboratory-scale electrode system consists of a discharge electrode and nine underwater grounding electrodes. Discharge emission on the water surface, which shows significant change with slight increase in conductivity, affects the current distribution in the water. The electric potential of the water surface also changes significantly with slight increase in conductivity. Results of numerical calculations of the underwater discharge current based on the water surface potential agree with the experimental results. 相似文献
77.
Annisa Nurul Aini Dunia Abdulaziz Al Farraj Endarko Endarko Agus Rubiyanto Hadi Nur Manal Mohammed Al Khulaifi Tony Hadibarata Achmad Syafiuddin 《中国化学会会志》2019,66(7):705-712
This study aims to evaluate the capability of Ageratum conyzoides and Mikania micrantha extracts to synthesize silver nanoparticles (AgNPs) and their antibacterial capability against gram‐positive and gram‐negative bacteria. Several properties of the synthesized AgNPs, including plasmonic, biomolecule bonding, shape, size, and antibacterial, were investigated. Ultraviolet–visible (UV–vis) spectroscopy was employed for characterizing their plasmonic properties. Functional groups on the produced AgNPs were investigated by Fourier‐transform infrared (FT‐IR) spectroscopy. The size and shape of the AgNPs were identified using the field‐emission scanning electron microscopy (FESEM). Inhibition zone measurement was carried out for evaluating the antibacterial capability. This study showed that the extracts of A. conyzoides and M. micrantha were able reducing agents as evidenced by the formation of the spherical AgNPs. UV–vis spectroscopy, FT‐IR spectroscopy, and FESEM confirmed the physicochemical characteristics of AgNPs. AgNPs that were synthesized using M. micrantha were slightly smaller than those produced using A. conyzoides. In general, the present work establishes that the synthesized AgNPs have antibacterial capability depending on their size and synthesis procedure. 相似文献
78.
Hakan Çiftçi Hasan Nur Testereci Zeki Öktem 《Russian Journal of Electrochemistry》2013,49(12):1160-1164
Conducting poly(2-aminothiazole) (PAT) films were electrodeposited on a platinum disc electrode surface by constant potential electrolysis of 2-aminothiazole (AT) for the stripping voltammetric determination of Ag(I). Ag(I) was preconcentrated on the polymer matrix by dipping the modified Pt electrode (PAT-Pt electrode) into Ag(I)(aq) solution. Effects of the film thickness, reduction potential, pH, preconcentration time, Ag(I) concentration and the interference of some other metal ions on the oxidation peak current of silver were studied. Cu(II) interference observed to be significant for the stripping voltammetric determination of Ag(I). The detection limit was calculated on the basis of signal to noise ratio of 3 as 2 × 10?7 mol L?1. 相似文献
79.
A capillary electrophoresis method for the separation of high-molecular-mass heparin oligosaccharides compatible with mass spectral detection was developed. Structurally defined heparin oligosaccharides ranging in size from tetrasaccharide to tetradecasaccharide were used to optimize the conditions. Applying normal and reversed polarity modes, these oligosaccharides were separated by CE under various conditions. Ammonium hydrogencarbonate (30 mM at pH 8.50) used as the running electrolyte system gave good separation efficiency and resolution in the normal polarity mode. Application of this method to the separation of complicated heparin oligosaccharide mixtures required the addition of electrolyte additives. Ammonium hydrogencarbonate (30 mM), containing triethylamine (10 mM), was useful for the separation of complex oligosaccharide mixtures. Run-to-run and day-to-day precision and limits of detection were established for these separations. 相似文献
80.
Rinda Hedwig Wahyu Setia Budi Syahrun Nur Abdulmadjid Marincan Pardede Maria Margaretha Suliyanti Tjung Jie Lie Davy Putra Kurniawan Koo Hendrik Kurniawan Kiichiro Kagawa May On Tjia 《Spectrochimica Acta Part B: Atomic Spectroscopy》2006,61(12):1285-1293
The applicability of spectrochemical analysis for liquid and powder samples of minute amount in the form of thin film was investigated using ultraviolet Nd-YAG laser (355 nm) and low-pressure ambient air. A variety of organic samples such as commercial black ink usually used for stamp pad, ginseng extract, human blood, liquid milk and ginseng powder was prepared as film deposited on the surface of an appropriate hard substrate such as copper plate or glass slide. It was demonstrated that in all cases studied, good quality spectra were obtained with very low background and free from undesirable contamination by the substrate elements, featuring ppm or even sub-ppm sensitivity and worthy of application for quantitative analysis of organic samples. The proper preparation of the films was found to be crucial in achieving the high quality spectra. It was further shown that much inferior results were obtained when the atmospheric-pressure (101 kPa) operating condition of laser-induced breakdown spectroscopy or the fundamental wavelength of the Nd-YAG laser was employed due to the excessive or improper laser ablation process. 相似文献