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排序方式: 共有641条查询结果,搜索用时 22 毫秒
631.
632.
Rao Priyashi Patel Rohit Shukla Arpit Parmar Paritosh Rawal Rakesh M. Saraf Meenu Goswami Dweipayan 《Molecular diversity》2022,26(1):309-329
Molecular Diversity - The non-structural protein (nsp)-3 of SARS-CoV2 coronavirus is sought to be an essential target protein which is also named as papain-like protease (PLpro). This protease... 相似文献
633.
Shubham Sharma Virender Singh Vaishali Rakesh Kumar Rahul Jamra Naveen Banyal Jyoti 《Journal of heterocyclic chemistry》2024,61(2):232-284
The synthesis of pyrazole derivative using α,β-unsaturated carbonyl compounds has attracted increasing attention of the synthetic organic chemist community. Interestingly, the simplicity of the synthetic method, high reactivity, and ease of incorporating diversity into the desired prototype have contributed a lot toward the exploration of α,β-unsaturated carbonyl compounds by various research groups. Due to the tremendous pharmacological significance of pyrazole derivatives, their synthesis has been one of the leading research frontiers in recent years. As prime examples, sildenafil, zometapin, Celebrex, and rimonabant have been successfully commercialized in the market to treat various life-challenging diseases. Considering the great profile of α,β-unsaturated carbonyl compound in the synthesis of biologically active pyrazole derivatives, this review incorporates contemporary literature (2011–2022) on the synthesis of pyrazole and its derivatives using α,β-unsaturated carbonyl compound as a starting precursor. 相似文献
634.
S. Selvakumar A. Arulchakkaravarthi Rakesh Kumar S. Muralithar S. Sankar K. Sivaji 《Solid State Communications》2008,145(9-10):482-486
635.
Focusing of a singular beam by a lens in the presence of spherical aberration and defocusing is studied by using Fresnel–Kirchhoff diffraction integral for two different values of topological charge. Results of intensity distribution and encircled energy are plotted for defocused observation planes. Spherical aberration spreads the dark core and reduces the intensity at maxima. The results have been verified by the optical transfer function (OTF) approach. 相似文献
636.
R. Thangavel Rakesh Singh Moirangthem Wei‐Shan Lee Yia‐Chung Chang Pei‐Kuen Wei J. Kumar 《Journal of Raman spectroscopy : JRS》2010,41(12):1594-1600
Undoped and cesium‐doped zinc oxide (ZnO) thin films have been deposited on sapphire substrate (0001) using the sol–gel method. Films were preheated at 300 °C for 10 min and annealed at 600 and 800 °C for 1 h. The grown thin films were confirmed to be of wurtzite structure using X‐ray diffraction. Surface morphology of the films was analyzed using scanning electron microscopy. The photoluminescence (PL) spectra of ZnO showed a strong ultraviolet (UV) emission band located at 3.263 eV and a very weak visible emission associated with deep‐level defects. Cesium incorporation induced a blue shift of the optical band gap and quenching of the near‐band‐edge PL for nanocrystalline thin film at room temperatures because of the band‐filling effect of free carriers. A shift of about 10–15 cm−1 is observed for the first‐order longitudinal‐optical (LO) phonon Raman peak of the nanocrystals when compared to the LO phonon peak of bulk ZnO. The UV resonant Raman excitation at RT shows multiphonon LO modes up to fifth order. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
637.
Intensity‐Enhanced Apodization Effect on an Axially Illuminated Circular‐Column Particle‐Lens 下载免费PDF全文
Liyang Yue Bing Yan James N. Monks Rakesh Dhama Zengbo Wang Oleg V. Minin Igor V. Minin 《Annalen der Physik》2018,530(2)
A particle can function as a refractive lens to focus a plane wave, generating a narrow, high intensive, weak‐diverging beam within a sub‐wavelength volume, known as the ‘photonic nanojet’. It is known that apodization method, in the form of an amplitude pupil‐mask centrally situated on a particle‐lens, can further reduce the waist of a photonic nanojet, however, it usually lowers the intensity at the focus due to blocking the incident light. In this paper, the anomalously intensity‐enhanced apodization effect was discovered for the first time via numerical simulation of focusing of the axially illuminated circular‐column particle‐lenses, and a greater than 100% peak intensity increase was realised for the produced photonic nanojets. 相似文献
638.
639.
To the best of our knowledge, we explore, for the very first time, the performance using Raman-EDFFA hybrid amplifier for super dense multiplexing system. We evaluate the system in terms of flat gain, noise figure, and good rating quality factor for L-band. A highest flat gain of 26.01 dB is observed over a wavelength range of 1,578 to 1,640 nm with a smaller variation of 1.5 dB without using any cost influence techniques. Further, we also observe that an input power level of ?25 dB is quite suitable for acceptable amplification. 相似文献
640.
Shweta D. Dabhi Swati Gahlot Sheefa Mirza Medha Pandya Rakesh Rawal Vaibhav Kulshrestha Prafulla K. Jha 《Macromolecular Symposia》2024,413(1):2300086
Graphene and graphene oxide (GO) have garnered significant attention due to their exceptional properties. GO, enriched with various functional groups such as epoxy, hydroxyl, and carboxylic groups, has exhibited remarkable potential in biomedical applications. The combination of GO with metals has proven to be a promising platform for cellular imaging, with this study focusing on the preparation of diverse hybrids of GO with metal oxides (GO/MO) and their potential as anticancer agents. In this research, GO is functionalized with MOs like TiO2, Fe3O4, and Cu2O using specific chemical methods and investigated for the anticancer activity for the application as cancer therapeutic agent. The resulting GO/MO hybrids exhibits favorable thermal and mechanical properties. Moreover, their cytotoxicity against human lung cancer cells is assessed in vitro, revealing the promising anticancer activity of GO/MO hybrids. Notably, the GO/Cu2O hybrid demonstrates particularly high cytotoxicity in human lung cancer cells. 相似文献