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排序方式: 共有436条查询结果,搜索用时 15 毫秒
81.
Leela Prasad Kowtharapu Naresh Kumar Katari Christian A Sandoval Siva Krishna Muchakayala Vijay Kumar Rekulapally 《Journal of separation science》2022,45(10):1711-1726
Serotonin receptor antagonist drug Ondansetron hydrochloride injectable formulation containing all related substances was identified and quantified by a single, simple, sensitive, eco-friendly, and green high-performance liquid chromatography method. The disseverment of all impurities was achieved with the Discovery Cyano (250 × 4.6) mm, 5 μm column. The gradient program was composed of pH 5.7 phosphate buffer as mobile phase A and acetonitrile as mobile phase B. The flow rate, column compartment temperature, and detection wavelengths were 0.9 mL/min, 30°C, and 216 nm, respectively. The method was validated as per current regulatory guidelines. The obtained %relative standard deviation for the precision results was between 0.55 and 2.72% for all impurities. The correlation coefficient values from the linearity experiment for impurities and analyte were more than 0.995. The accuracy results were obtained between 88.4 and 113.0% for all impurities. Both sample and standard solutions showed 24 h stability at benchtop and refrigerator conditions. All impurities and analytes met the specificity and mass balance for all forced degradation conditions. Quality-by-design-based design of experiments was utilized to establish the method's robustness. Method greenness was assessed by using the current advanced tool green analytical procedure index, National Environmental Methods Index, and analytical eco-scale. 相似文献
82.
Tripathy Debajani Chakroborty Subhendu Gadtya Ankita Subhrasmita Mahaling Ram Naresh Moharana Srikanta Barik Arundhati Pal Kaushik 《The European physical journal. E, Soft matter》2023,46(3):1-13
The European Physical Journal E - We discuss the lateral dynamics of two active force dipoles, which interact with each other via hydrodynamic interactions in a thin fluid layer that is active and... 相似文献
83.
F. Albert Cotton Naresh S. Dalal Narpinder Kaur Carlos A. Murillo Mark D. Young Qinliang Zhao 《Journal of Cluster Science》2010,21(3):301-312
Oxidation of α-[Mo2(cis-DAniF)2]3(μ-F)6 with an excess of FeCp2BF4 produces the triply oxidized species {β-[Mo2(cis-DAniF)2]3(μ-F)6}(BF4)3. During the oxidation process, the conformation in the α triangular species changes from an arrangement in which two dimetal units are parallel and the third one essentially orthogonal to a structure in which all three dimetal units are parallel. Furthermore, upon removal of three electrons, the Mo–Mo distances increase by about 0.05–0.06 Å and the Mo–F bond distances decrease by 0.04 Å. The structural data, as well as EPR, are consistent with an electronically localized system and a decrease in bond order from 4 to 3.5 for each dimetal unit. 相似文献
84.
Naresh Kumar Mani Sankha Shuvra Das Sayantan Dawn Suman Chakraborty 《Electrophoresis》2020,41(7-8):615-620
Enhancing the sensitivity of colorimetric detection in paper-devices is a quintessential step in achieving frugal diagnosis. Here, we demonstrate an effective way of improving the detection sensitivity of paper-based devices, as mediated by electro-kinetic mechanisms. By directly employing blood plasma, we investigate the electro-kinetic clustering of glucose, a neutral molecule in paper devices. Under the influence of uniform electric field, dispersed glucose gets accumulated in the paper strips. Due to the combination of EOF and electrophoretic migration, we achieve twofold increase in the colour intensity for both normal and diabetic samples. This approach is robust and possesses better sensitivity than conventional colorimetric assays and can be easily extended to other body fluid based diagnosis. These results may turn out to be of profound importance in improving the quality of pathological diagnosis in low-cost paper-based point-of-care devices deployed in resource-limited settings. 相似文献
85.
86.
Naresh Kumar Shiva Prasad D.S. Misra N. Venkataramani Murtaza Bohra R. Krishnan 《Journal of magnetism and magnetic materials》2008
Yttrium iron garnet (YIG) thin films were deposited on fused quartz substrate at different substrate temperatures (Ts) varying from room temperature (RT) to 850 °C using pulsed laser deposition (PLD) technique. All the films in the as-deposited state were X-ray amorphous and non-magnetic at RT. The film deposited at RT after annealing at temperatures Ta?700 °C showed both X-ray peaks and the magnetic order. The films deposited at higher Ts (500–850 °C) and then annealed at 700 °C resulted in better-quality films with higher 4πMs value. The highest value of magnetization was for the sample deposited at 850 °C and annealed at 700 °C, which is 68% of the bulk 4πMs value. 相似文献
87.
Naresh Kumar Mahalingavelar Paramasivam Jagdeep Kumar Anamika Gusain Prasanta Kumar Hota 《Journal of fluorescence》2018,28(5):1207-1216
Various electron donor and acceptor substituted (NO2, CN, Cl, H, OCH3, NH2) p-phenyl ethenyl-E- thiophenes (1–6) were synthesized and substituent dependent optical properties (dipole moment, transition dipole moment, oscillator strength, optical band gap, hyperpolarizability) were studied using Solvatochromism and Density functional theory. It is shown that thiophene acts as a weak electron donor in presence of an electron withdrawing p-phenyl substituent (NO2, CN, Cl), whereas thiophene acts as a weak electron acceptor in presence of an electron donating p-phenyl substituent (OCH3, NH2). In comparison to ethenyl thiophene 4, the HOMO-LUMO energy band gap is decreased upon increasing the electron donating or electron withdrawing capacity of p-phenyl substituent. From the excited state dipole moment calculation, it is shown that the excited state is highly dipolar for nitro and amino compounds 1 and 6, whereas compounds 2–5 show a non-polar excited state. As compared to the ethenyl thiophene 4, the first hyperpolarizability (β) increases upon substitution either with a strong electron withdrawing or strong electron donating p-phenyl substituent. A large β value is found for p-nitro phenyl ethenyl-E-thiophene and p-amino phenyl ethenyl-E- thiophene. Overall, these studies provide useful information in understanding the optical properties of phenyl and heterocyclic based ethenyl systems. 相似文献
88.
Naresh Kumar Emani Di Wang Ting‐Fung Chung Ludmila J. Prokopeva Alexander V. Kildishev Vladimir M. Shalaev Yong P. Chen Alexandra Boltasseva 《Laser \u0026amp; Photonics Reviews》2015,9(6):650-655
Plasmon resonances in nanopatterned single‐layer graphene nanoribbons (SL‐GNRs), double‐layer graphene nanoribbons (DL‐GNRs) and triple‐layer graphene nanoribbons (TL‐GNRs) are studied experimentally using ‘realistic’ graphene samples. The existence of electrically tunable plasmons in stacked multilayer graphene nanoribbons was first experimentally verified by infrared microscopy. We find that the strength of the plasmonic resonance increases in DL‐GNRs when compared to SL‐GNRs. However, further increase was not observed in TL‐GNRs when compared to DL‐GNRs. We carried out systematic full‐wave simulations using a finite‐element technique to validate and fit experimental results, and extract the carrier‐scattering rate as a fitting parameter. The numerical simulations show remarkable agreement with experiments for an unpatterned SLG sheet, and a qualitative agreement for a patterned graphene sheet. We conclude with our perspective of the key bottlenecks in both experiments and theoretical models.
89.
Optical CDMA over FSO communication system is very effective to provide high data rate transmission with very low bit error rate and low amount of multiple access interference. In this paper, we have presented optical CDMA over FSO communication system to the range of 8000 m. The simulative results reveal that the transmission distance is limited mainly by the multi-access interference (MAI) which arises when there are number of users in the system because of the fact that one user data becomes noisy for all other users in the channel. 相似文献
90.
Studies on Synthesis of Novel Triazole Tagged Pyrazole Fused Naphthalene 5‐Thiazine‐5,5‐dioxide Derivatives,Their Antimicrobial,and Antioxidant Activity 下载免费PDF全文
G. Malla Reddy P. Nagender R. Naresh Kumar J. H. Ahn K. Pranay Kumar A. K. R. Kanugula K. V. S. Rama Krishna S. Kotamraju B. Narsaiah 《Journal of heterocyclic chemistry》2014,51(Z1):E42-E49
A series of novel triazole tagged pyrazole fused naphthalene‐5‐thiazine‐5,5‐dioxide derivatives 8 and 9 were synthesized starting from sodium salt of saccharin 1 . The structure of each intermediate and products was established on the basis of spectroscopy data. All the synthesized compounds 8 and 9 were screened against various bacterial and fungal strains but found to show no activity up to 150‐µg/mL concentration. Further screening for antioxidant property resulted promising compounds. 相似文献