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121.
Yongjun Liu Nur Fadhilah Ibrahim 《Journal of Computational and Applied Mathematics》2010,235(1):286-292
In this paper we propose an iterative method to calculate the largest eigenvalue of a nonnegative tensor. We prove this method converges for any irreducible nonnegative tensor. We also apply this method to study the positive definiteness of a multivariate form. 相似文献
122.
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
123.
Esen Ayse Nur Haciyakupoglu Sevilay Erenturk Sema 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(3):677-683
Journal of Radioanalytical and Nuclear Chemistry - Proficiency testing is an important way of evaluating the analytical method used in the laboratory. In recent years, neutron activation analysis... 相似文献
124.
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
125.
126.
This study investigated the properties of immobilized β-galactosidase on polymeric beads having Schiff base. Polystyrene microspheres attached L-Alanine (FMPS-Ala) was synthesized from (4-formyl-3-methoxyphenoxymethyl)polystyrene (FMPS) and L-alanine by condensation. A coordinasyon polymer involving Ni2+(FMPS-Ala-Ni) was produced with the template method and characterized. β-galactosidase was immobilized onto the (FMPS), (FMPS-Ala) and (FMPS-Ala-Ni) complexes via covalent bonds. The Km/Vmax values were calculated as 0.343 mM/0.0259 mM min?1for free β-galactosidase and 0.104 mM/0.0126 mM min?1, 0.0617 mM/0.0417 mM min?1and 0.210 mM/0.0287 mM min?1for β-galactosidase immobilized to the (FMPS), (FMPS-Ala) and (FMPS-Ala-Ni) supports, respectively. The storage stability of (FMPS-Ala-Ni) was determined to be higher than that of the (FMPS) and (FMPS-Ala) polymers. 相似文献
127.
A kinetic spectrophotometric method has been described for the determination of metoprolol tartrate in commercial dosage forms. The procedure is based on the reaction of the drug with 1‐chloro‐2, 4‐dinitrobenzene (CDNB) in dimethylsulfoxide (DMSO) at 100 ± 1 °C. The reaction is investigated by measuring the change in absorbance with time at 420 nm. Fixed‐time (ΔA) and equilibrium methods are chosen for obtaining the calibration curves. Both calibration curves were found to be linear over the concentration range of 5‐60 μg mL?1. The regression analysis of calibration data resulted in the linear regression equations of ΔA = ?1.608 × 10?4 + 3.96 × 10?3 C and A = 7.31 × 10?4 + 1.90 × 10?2 C for fixed time (ΔA) and equilibrium methods, respectively. The limit of detection (LOD) for fixed time and equilibrium methods are 1.16 and 0.415 μg mL?1, respectively. The method has been successfully applied to the quantitation of metoprolol tartrate in commercial dosage forms. Statistical comparison of the results shows that there is no significant difference between the proposed methods and El‐Ries's spectrophotometric method. 相似文献
128.
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
129.
Norwahyu Jusoh Thiam Leng Chew Kok Keong Lau Azmi Mohd Shariff 《Separation & Purification Reviews》2016,45(4):321-344
In the early stage of membrane technology development in gas separation, utilization of polymeric membranes has gained attention due to their robustness and ease of fabrication. However, the performance of polymeric membranes is limited by the trade-off between permeability and selectivity. Meanwhile, inorganic membrane is capable to exhibit great enhancement in separation performance but unfortunately its fabrication process is hard and costly. Thus, development of mixed matrix membranes (MMMs) by incorporating inorganic fillers into the polymer matrix has become a potential alternative to overcome the limitations of polymeric and inorganic membranes in gas separation. Nevertheless, fabrication of defect-free MMMs with improved separation performance and without compromising the mechanical and thermal stability is extremely difficult and challenging. In the current review paper, various types of inorganic fillers for MMMs fabrication and recent reported efforts to tailor the underlying problems on MMMs fabrication were discussed. The future outlook to advance the performance of MMMs in gas separation especially for CO2/CH4 separation was highlighted. 相似文献
130.
Ridhuan Nur Syafinaz Mohamad Nor Noorhashimah Abdul Razak Khairunisak Lockman Zainovia Zakaria Nor Dyana 《Journal of Solid State Electrochemistry》2021,25(3):1065-1072
Journal of Solid State Electrochemistry - This work demonstrated the property enhancement of Pt nanodendrite (PtNDs)-decorated ZnO nanorods (ZnONRs) modified indium tin oxide (ITO) electrode for an... 相似文献