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排序方式: 共有543条查询结果,搜索用时 15 毫秒
31.
Gadkari Yatin U. Hatvate Navnath T. Telvekar Vikas N. 《Research on Chemical Intermediates》2021,47(10):4245-4255
Research on Chemical Intermediates - Concentrated solar radiation (CSR)-assisted synthesis of pyranopyrazole derivatives under solvent and catalyst-free condition has been reported in the present... 相似文献
32.
33.
Vikas Shringi Surendra Kothari N. L. Panwar 《Journal of Thermal Analysis and Calorimetry》2014,118(1):533-539
This investigation deals with thermodynamic analysis, which offers an alternative approach to evaluate the performance of solar dryers and thin-layer drying characteristics of garlic cloves in a developed system. The garlic cloves were dried from a moisture content of 55.5 % (w.b.) to 6.5 % (w.b.) for 8 h. The drying data obtained were fitted to five different drying kinetics models. Of these, the model suggested by Midilli et al. [28] had the best fit with the drying behavior of garlic cloves. The energy efficiency without and with recirculation of the air exiting the drying chamber during the study varied from 43.06 to 83.73 %, and 3.98 to 14.95 %, respectively, while the exergy efficiency corresponding to the energy efficiency of the drying process ranged from 5.01 to 55.30 % and 67.06 to 88.24 %, respectively. 相似文献
34.
Jagjeet Kaur Ravi Shrivastava Vikas Dubey Beena Jaykumar 《Research on Chemical Intermediates》2014,40(8):2599-2604
This paper reports thermoluminescence glow curves of Eu3+, Dy3+-doped Ba2MgSi2O7 phosphor for different UV exposure times. Kinetic data were evaluated by the peak-shape method. The glow curves shift toward higher intensity with increasing exposure time to UV at 365 nm. When the heating rate was 5 °C s?1, peaks were observed at 101.76, 109.69, 102.67, and 104.05 °C, respectively, after UV exposure for 5, 10, 15, and 20 min. The glow peaks are indicative of second-order kinetics. Different kinetic data, i.e. trap depth, order of kinetics, activation energy, and frequency factor were also calculated. To evaluate the persistence characteristics of the luminescence of the phosphor, the lifetime of the charge in the trap was calculated; it was 348, 660, 368, and 428 s for UV exposure of 5, 10, 15, and 20 min, which indicates the luminescence of the phosphor is persistent. 相似文献
35.
Sharma Abhishek K. Agrahari Gaurav Tiwari C. B. Tomar B. S. Yelgaonkar V. N. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):143-147
Journal of Radioanalytical and Nuclear Chemistry - In the traditional medicine of Iran, some herbal medicines are used for treating of high blood sugar. In this study, the concentration of Ca, Cr,... 相似文献
36.
Sharma Deepika Radha Anu Kumar Pretam Kumar Sandeep Jassal Amanpreet K. Lata Suman Vikas Pandey Sushil K. 《Transition Metal Chemistry》2020,45(8):531-544
Transition Metal Chemistry - Nickel(II) complexes with octahedral coordination stabilized by N-donor ligands corresponds to [{(ArO)2PS2}2Ni·L2] [Ar = 4-(C2H5)C6H4 (3), and... 相似文献
37.
Mandeep Kumar Arora Anish Ratra Syed Mohammed Basheeruddin Asdaq Ali A. Alshamrani Abdulkhaliq J. Alsalman Mehnaz Kamal Ritu Tomar Jagannath Sahoo Jangra Ashok Mohd Imran 《Molecules (Basel, Switzerland)》2022,27(6)
Plumbagin, a hydroxy-1,4-naphthoquinone, confers neuroprotection via antioxidant and anti-inflammatory properties. The present study aimed to assess the effect of plumbagin on behavioral and memory deficits induced by intrahippocampal administration of Quinolinic acid (QA) in male Wistar rats and reveal the associated mechanisms. QA (300 nM/4 μL in Normal saline) was administered i.c.v. in the hippocampus. QA administration caused depression-like behavior (forced swim test and tail suspension tests), anxiety-like behavior (open field test and elevated plus maze), and elevated anhedonia behavior (sucrose preference test). Furthermore, oxidative–nitrosative stress (increased nitrite content and lipid peroxidation with reduction of GSH), inflammation (increased IL-1β), cholinergic dysfunction, and mitochondrial complex (I, II, and IV) dysfunction were observed in the hippocampus region of QA-treated rats as compared to normal controls. Plumbagin (10 and 20 mg/kg; p.o.) treatment for 21 days significantly ameliorated behavioral and memory deficits in QA-administered rats. Moreover, plumbagin treatment restored the GSH level and reduced the MDA and nitrite level in the hippocampus. Furthermore, QA-induced cholinergic dysfunction and mitochondrial impairment were found to be ameliorated by plumbagin treatment. In conclusion, our results suggested that plumbagin offers a neuroprotective potential that could serve as a promising pharmacological approach to mitigate neurobehavioral changes associated with neurodegeneration. 相似文献
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39.
A lossy mode resonance (LMR)-supported fiber optic sensor in which a uniform fiber core is placed among two identical tapered regions, is investigated numerically. Indium tin oxide (ITO) and aluminum-doped zinc oxide (AZO) are considered as LMR active materials used to excite several lossy modes and gold and silver are used as surface plasmon resonance (SPR) active materials. In this probe design, a central uniform core coated with ITO/AZO is the active sensing region, whereas tapered regions are meant for bringing the incident angle close to the critical angle. The sensitivity of the present fiber optic bio-sensor is evaluated for first two LMRs utilizing both ITO and AZO separately, along with its variation with the taper ratio (TR). For ITO, the maximum sensitivity values are observed to be 18.425 μm RIU−1 (refractive index unit) and 0.825 μm RIU−1, corresponding to the first and second LMRs, respectively, at a TR of 1.6 and for AZO, equivalent values are 0.79 μm RIU−1 and 0.35 μm RIU−1, respectively, at a TR of 2.0. The results illustrate that the first LMR is more sensitive than the second LMR and the ITO-coated probe possesses greater sensitivity than the AZO-coated probe for both LMRs. Similarly, for the fiber optic SPR sensor, the maximum value of sensitivity is 5.6425 μm RIU−1, in the case of gold and 5.0615 μm RIU−1 in the case of silver, at a TR of 1.6. Hence, the result shows that the sensor with the present fiber optic probe design has around a 3-fold enhancement in sensitivity compared with conventional SPR sensors. This study will have applications in many sensing schemes where the requirement of large sensitivity is vital. 相似文献
40.
A simple, efficient, and ecofriendly procedure has been developed for the synthesis of quinoline and its derivatives in a one-pot reaction of aniline with crotonaldehyde or methyl vinyl ketone using phosphomolybdic acid as solid acid catalyst in miceller media. The catalyst was easily recycled and reused. 相似文献