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71.
A Fourier-synthesized 40-GHz optical pulse train was successfully synchronized to an 8-GHz optical clock generated from a mode-locked fiber ring laser. The measured timing jitter of the synchronization was 0.43 ps. 相似文献
72.
The diols (7) and (8) are cyclised to the dienes (10) and (11) with loss of the secondary hydroxyl group. 相似文献
73.
Madhukar N. Jachak Sandeep M. Bagul Muddassar A. Kazi Raghunath B. Toche 《Journal of heterocyclic chemistry》2011,48(2):295-300
Novel pyrazolo[3,4‐h][1,6]naphthyridine derivatives 6 , 8 , 9 , 11 , 13 , and 15 have been synthesized by Friedlander condensation of new 4‐amino‐3‐methyl‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyridine‐5‐carbaldehyde (o‐aminoaldehyde) 4 with active methylene ketones, such as symmetric acetone 5a , monoalkylketones 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 5k , unsymmetrical dialkyl ketones 7a , 7b , p‐bromophenylacetonitrile 10 , β‐ketoester 12a , β‐ketoamide 12b , or diethyl malonate 14 , respectively. J. Heterocyclic Chem., (2011). 相似文献
74.
We demonstrate fiber distributed feedback (DFB) lasers using Raman gain in two germanosilicate fibers. Our DFB cavities were 124 mm uniform fiber Bragg gratings with a π phase shift offset from the grating center. Our pump was at 1480 nm and the DFB lasers operated on a single longitudinal mode near 1584 nm. In a commercial Raman gain fiber, the maximum output power, linewidth, and threshold were 150 mW, 7.5 MHz, and 39 W, respectively. In a commercial highly nonlinear fiber, these figures improved to 350 mW, 4 MHz, and 4.3 W, respectively. In both lasers, more than 75% of pump power was transmitted, allowing for the possibility of substantial amplification in subsequent Raman gain fiber. 相似文献
75.
Manirul Islam Sanchita Mondal Paramita Mondal Anupam Singha Roy Kazi Tuhina Noor Salam Sumantra Paul Dildar Hossain Manir Mobarok 《Transition Metal Chemistry》2011,36(4):447-458
Immobilization of copper onto polystyrene provided a polymer-supported copper(II) catalyst, which was effective in cross-coupling
reactions between N-containing substrates and arylboronic acids using methanol as a solvent in air under base-free conditions. This catalyst
was also effective in N-arylation of imidazole with aryl halides in DMSO using K2CO3 as a base under nitrogen atmosphere. The catalyst was characterized by physico-chemical and spectroscopic techniques. The
product N-arylimidazoles and N-arylbenzimidazoles were isolated in good to excellent yields. This copper catalyst was air stable and could be recycled with
minimal loss of activity. 相似文献
76.
Investigation of viscosity and thermal conductivity of alumina nanofluids with addition of SDBS 总被引:1,自引:0,他引:1
B. LotfizadehDehkordi S. N. Kazi M. Hamdi A. Ghadimi E. Sadeghinezhad H. S. C. Metselaar 《Heat and Mass Transfer》2013,49(8):1109-1115
The present study focused on thermal conductivity and viscosity of alumina nanoparticles, at low volume concentrations of 0.01–1.0 % dispersed in the mixture of ethylene glycol and water (mass ratio, 60:40). Sodium dodeobcylbenzene sulfonate (SDBS) was applied for better dispersion and stability of alumina nanoparticles and study of its influence on both thermal conductivity and viscosity. The thermal conductivity established polynomial enhancement pattern with increase of volume concentration up to 0.1 % while linear enhancement was obtained at higher concentrations. In addition, thermal conductivity was enhanced with the rise of temperature. However, the augmentation was negligible compared to that obtained with increase of volume concentration. In contrast, viscosity data showed remarkable reduction with increase of temperature. Meanwhile, viscosity of nanofluids enhanced with loading of alumina nanoparticles. Thermal conductivity and viscosity measurements showed higher values over theoretical predictions. Results showed SDBS at different concentrations has distinct influence on thermal conductivity and viscosity of nanofluid. 相似文献
77.
Raghunath B. Toche Bhausaheb K. Ghotekar Muddassar A. Kazi Madhukar N. Jachak 《Monatshefte für Chemie / Chemical Monthly》2009,140(2):235-241
Abstract A novel method for the synthesis of 3-(2-substituted ethyl)-2-methylbenzohetero[3,2-a]pyrimidines in high yield (80–85%) was achieved, which involves a dihydrofuranone intermediate, readily obtained from β-ketolactone
to 2-aminobenzoheterocycles. The major advantage of the methodology is the high yield and product purity.
Graphical Abstract
相似文献
78.
We demonstrate a soliton self-frequency shift of approximately 120 nm in a fiber with 1.56-microm pulses generated at a 10-GHz repetition rate by an actively mode-locked laser. A highly nonlinear photonic crystal fiber with a length of only 12.6 m and a nonlinear coefficient of 62 W(-1) km(-1) is used to achieve such broadband operation. The wavelengths of the resulting sub-300-fs solitons can be tuned effectively by adjusting the input power. The maximum output power of the solitons exceeds 200 mW. 相似文献
79.
Islam Mohammad Rakibul Iftekher A. N. M. Hasan Kazi Rakibul Nayen Md. Julkar Islam Saimon Bin Hossain Aadreeta Mustafa Zareen Tahsin Tahia 《Optical and Quantum Electronics》2021,53(2):1-17
Optical and Quantum Electronics - Optical sensors are very attractive in chemical and bio-chemical applications due to some unique characteristics, such as immunity to electromagnetic interference... 相似文献
80.
Siraj Uddin Javed Iqbal Luqman Bin Safdar Saleem Ahmad Banzeer Ahsan Abbasi Raffaele Capasso Mohsin Kazi Umar Masood Quraihi 《Molecules (Basel, Switzerland)》2022,27(7)
An eco-friendly biogenic method for the synthesis of nickel oxide nanoparticles (NiONPs) using phytochemically rich Berberis pachyacantha leaf extract (BPL) was established. To achieve this purpose, 80 mL of BPL extract was used as a suitable reducing and capping agent for the synthesis of NiONPs. The synthesis of BPL-based nickel oxide nanoparticles (BPL@NiONPs) was confirmed using different microscopic and spectroscopic techniques: UV Visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray (EDX), dynamic light scattering (DLS) and scanning electron microscopy (SEM) analysis. Spectroscopically, BPL-NiONPs was found with a pure elemental composition (oxygen and nickel), average size (22.53 nm) and rhombohedral structure with multiple functional groups (-OH group and Ni-O formation) on their surface. In the next step, the BPL extract and BPL@NiONPs were further investigated for various biological activities. As compared to BPL extract, BPL@NiONPs exhibited strong biological activities. BPL@NiONPs showed remarkable antioxidant activities in terms of 2,2-diphenyl-1-picrylhydrazyl (76.08%) and total antioxidant capacity (68.74%). Antibacterial action was found against Pseudomonas aeruginosa (27 mm), Staphylococcus aureus (20 mm) and Escherichia coli (19.67 mm) at 500 µg/mL. While antifungal potentials were shown against Alternaria alternata (81.25%), Fusarium oxysporum (42.86%) and Aspergillus niger (42%) at 1000 µg/mL. Similarly, dose-dependent cytotoxicity response was confirmed against brine shrimp with IC50 value (45.08 µg/mL). Additionally, BPL@NiONPs exhibited stimulatory efficacy by enhancing seed germination rate at low concentrations (31.25 and 62.5 µg/mL). In conclusion, this study depicted that BPL extract has important phytochemicals with remarkable antioxidant activities, which successfully reduced and stabilized the BPL@NiONPs. The overall result of this study suggested that BPL@NiONPs could be used as nanomedicines and nanofertilizers in biomedical and agrarian fields. 相似文献