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911.
Hybrid plasmonic waveguides consisting of a metal plane separated from a high-index medium by a low-index spacer have recently attracted much interest. Here we show that, by suitably choosing the dimensions and material properties of the hybrid waveguide, a very compact and broadband TE-pass polarizer can be implemented. Finite-difference time-domain simulation indicates that the proposed device can provide large extinction ratio with low insertion loss for the TE mode. 相似文献
912.
Siddiquey IA Furusawa T Sato M Bahadur NM Alam MM Suzuki N 《Ultrasonics sonochemistry》2012,19(4):750-755
In this paper, we report the synthesis of silica coated ZnO nanoparticles by ultrasound irradiation of a mixture of dispersion of ZnO, tetraethoxysilane (TEOS), and ammonia in an ethanol-water solution medium. The silica coating layer formed at the initial TEOS/ZnO loading of 0.8 for 60 min ultrasonic irradiation was uniform and extended up to 3 nm from the ZnO surface as revealed from HR-TEM images. Silica coated ZnO nanoparticles demonstrated a significant inhibition of photocatalytic activity against photodegradation of methylene blue dye in aqueous solution. The effects of silica coating on the UV blocking property of ZnO nanoparticles were also studied. 相似文献
913.
S. Sankar MR. Manikandan S.D. Gopal Ram T. Mahalingam G. Ravi 《Journal of Crystal Growth》2010,312(19):2729-2733
The microbial free single crystals of α and γ glycine were grown from gel at room temperature in a new chemical route. These crystals showed a superior quality than the solution grown crystals. The metastable α-form and the stable γ-form of glycine were crystallized in silica gel by solubility reduction method. The form of crystallization is confirmed by single crystal and powder X-ray diffraction analyses. The crystals of α and γ glycine were found to crystallize in monoclinic and hexagonal crystal systems, respectively. For analyzing the functional group and thermal stability of α and γ glycine crystals, spectroscopic and thermal analyses have been carried out. The dielectric studies were performed to find the dielectric constant of the grown crystals and the results are discussed. Second harmonic generation efficiency of the crystal was measured by Kurtz’s powder method using Nd:YAG laser and it was found to be 2.68 times that of potassium dihydrogen phosphate crystals. 相似文献
914.
Mohammed F. Arshad Aftab Alam Abdullah Ayed Alshammari Mohammed Bader Alhazza Ibrahim Mohammed Alzimam Md Anish Alam Gulam Mustafa Md Salahuddin Ansari Abdulelah M. Alotaibi Abdullah A. Alotaibi Suresh Kumar Syed Mohammed Basheeruddin Asdaq Mohd. Imran Pran Kishore Deb Katharigatta N. Venugopala Shahamah Jomah 《Molecules (Basel, Switzerland)》2022,27(13)
915.
Vijayanath S. Janaki K. Gopal Ramalingam Ragupathi C. Rangasamy Baskaran Alam Mohammed Mujahid 《Journal of Solid State Electrochemistry》2023,27(1):183-194
Journal of Solid State Electrochemistry - In the present study, a novel cost-effective and efficient configuration of dye-sensitized solar cell (DSSC) with zinc oxide–multi-walled carbon... 相似文献
916.
917.
During annealing of Ni and Au, previously quenched into HCl at 203 K, annealing stages that cannot easily be explained in terns of the migration of open volume defects are observed. The contamination of the hot samples with hydrogen released from the quenching fluid is suggested as the origin of these additional annealing stages. 相似文献
918.
Michael A. Hickner Gregory J. Tudryn Todd M. Alam Michael R. Hibbs Cy H. Fujimoto 《Macromolecular Symposia》2009,279(1):59-62
Ionic clustering, water binding, and ion conductivity were studied in polymers functionalized with sulfonic acid and quaternary ammonium hydroxide groups. Small-angle x-ray scattering showed that no clustering occurred in the quaternary ammonium containing anion exchange membranes, while evidence of ionic clusters was present in both sulfonated poly(phenylene) and in Nafion, a poly(perfluorosulfonic acid). Interestingly, the water self-diffusion coefficients of the anion exchange membranes were generally greater than those observed for the sulfonated poly- (phenylene)s, and moreover, the water self diffusion coefficients in anion exchange membranes were not a strong function of diffusion time. The water binding behavior lead to increased normalized conductivity in anion exchange membranes as compared to proton exchange membranes at the highest ion exchange capacities. 相似文献
919.
920.
Syed Dilshad Alam Mirza Adil Beg Muralidhararao Bagadi Marcello Locatelli Zeid A. ALOthman Mohd Mustaqeem Imran Ali 《Journal of separation science》2023,46(21):2300582
The extraction of berberine was carried out from Berberis vulgaris, Berberis aquifolium, and Hydrastis canadensis plants using ethanol and water (70:30, v/v). The extracted berberine was characterized by ultraviolet-visible and Fourier-transform infrared spectroscopy. The purity of berberine was ascertained by thin-layer chromatography using n-propanol-formic acid-water (95:1:4) and (90:1:9) solvents. hRf values were in the range of 44–49 with compact spots (diameter 0.2–0.4 cm). HPLC was carried out using ammonium acetate buffer and acetonitrile in gradient mode with Zodiac (4.6 × 150 mm, 3 μm) column. The flow rate was 1.0 mL/min and detection was at 220 nm. The values of separation and resolution factors of the standard and the extracted berberine were in the range of 1.13–1.16 and 1.40–1.71, respectively. A comparison has shown that both thin-layer chromatography and high-performance liquid chromatography (HPLC) methods found applications in different situations and requirements. The extracted berberine samples were used to treat Leishmaniosis and the results showed better activity of berberine in comparison to the standard drug Amphotericin B. Briefly, the reported research is a novel and may be used to extract berberine from plants, separation and identification of berberine by thin layer chromatography and HPLC and to treat Leishmaniosis. 相似文献