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排序方式: 共有829条查询结果,搜索用时 31 毫秒
811.
Parikshit Moitra Maria Iftesum David Skrodzki Priyanka Paul Elnaz Sheikh Jennifer Lynn Gray Ketan Dighe Zach Sheffield Manas Ranjan Gartia Dipanjan Pan 《Advanced functional materials》2023,33(19):2212569
Liquid interfaces facilitate the organization of nanometer-scale biomaterials with plasmonic properties suitable for molecular diagnostics. Using hierarchical assemblage of 2D hafnium disulfide nanoplatelets and zero-dimensional spherical gold nanoparticles, the design of a multifunctional material is reported. When the target analyte is present, the nanocomposites’ self-assembling pattern changes, altering their plasmonic response. Using monkeypox virus (MPXV) as an example, the findings reveal that adding genomic DNA to the nanocomposite surface increases the agglomeration between gold nanoparticles and decreases the π-stacking distance between hafnium disulfide nanoplatelets. Further, this self-assembled nanomaterial is found to have minimal cross-reactivity toward other pathogens and a limit of detection of 7.6 pg µL−1 (i.e., 3.57 × 104 copies µL−1) toward MPXV. Overall, this study helped to gain a better understanding of the genomic organization of MPXV to chemically design and develop targeted nucleotides. The study has been validated by UV–vis spectroscopy, X-ray diffraction, scanning transmission electron microscopy, surface-enhanced Raman microscopy and electromagnetic simulation studies. To the best knowledge, this is the first study in literature reporting selective molecular detection of MPXV within a few minutes and without the use of any high-end instrumental techniques like polymerase chain reactions. 相似文献
812.
Satish Ranjan Pradhan Vishwa Mohan Behera Sushil Kumar Rathore Jnana Ranjan Senapati 《亚洲传热研究》2023,52(2):1754-1777
The present numerical study reports the combined effect of natural convection and radiation heat from a vertical cylinder with annular fins. The study involves simulation for laminar as well as turbulent regimes. For the present study, Rayleigh's number is varied in the range , emissivity in the range , and the fin spacing ratio (s/d) in the range . The radiation heat transfer has been found to share a considerable amount in the total heat transfer of the system for the laminar regime, but in the turbulent regime, its effect is minimal and can be neglected. When the fin spacing ratio is reduced, the total heat transfer increases for both the turbulent and laminar flow conditions. But the radiation heat increases with a reduction in fin spacing ratio for laminar and in case of turbulent flow radiation heat rate reduces with a reduction in s/d ratio. For the range of Rayleigh numbers considered in the present study, the Nusselt number increases with the increment of the fin spacing ratio. Thus, it can be concluded that there is a remarkable enhancement in the heat transfer rate in laminar cases with the fins. For turbulent cases, the fin efficiency lies between 40% and 50%. 相似文献
813.
Dr. Ranjan K. Mohapatra Dr. Venkataramana Kandi Dr. Sarika Verma Dr. Kuldeep Dhama 《Chembiochem : a European journal of chemical biology》2022,23(9):e202200059
The SARS-CoV-2 virus has shown increased ability to mutate over the past two years, especially in the regions of the spike protein and receptor binding sites. Omicron (B.1.1.529) is the fifth variant of concern (VOC) after the emergence of the Alpha, Beta, Gamma, and Delta VOCs of SARS-CoV-2. This new variant has now circulated in 128 countries and according to the Global Initiative on Sharing All Influenza Data (GISAID), these 128 countries have shared 650,657 Omicron genome sequences as of 26 January, 2022. In this article, we highlight the real challenges of Omicron and its different lineages. 相似文献
814.
Sunil Kumar Saikat Ranjan Maity Lokeswar Patnaik 《International Journal of Applied Ceramic Technology》2022,19(3):1678-1690
TiAlN film was deposited on Cr2O3-coated plasma-nitrided DAC-10 tool steel to obtained multilayer Cr2O3/TiAlN coating layer using cathodic arc deposition technique. The structural make-up of the coating was characterized using Atomic Force Microscopy (AFM) and X-ray diffraction methods, and the mechanical properties were evaluated using nanoindentation and nanoscratch test. The structural phases of the coating indicated the presence of crystalline CrO structure and cubic TiAlN phases. The coating showcased improved hardness (38 GPa), elastic modulus (387 GPa), and adhesion along with appreciable H/E (0.09) and H3/E2 (0.366 GPa) attributes. Further, friction-induced wear behavior of the coating was investigated against steel and Al2O3 counterbodies under dry sliding conditions. The wear behavior of the coating was greatly influenced by its hardness and deformation properties and frictional behavior of the counterbodies. More spikes and fluctuation were observed in the frictional curve against Al2O3 counterbody attributed to the emanation of TiO2, Cr2O3, and Al2O3 compounds due to dry sliding leading to the formation of flakes and delamination induced debris. Against the steel counterbody, the coating mainly formed a typical smooth glossy surface ascribed to the formation of Fe2O3 compound on the worn surface. 相似文献
815.
Pradhan Smruti Ranjan Singh Rupinder Banwait Sukhwant Singh 《Journal of Mechanical Science and Technology》2022,36(8):4197-4203
Journal of Mechanical Science and Technology - DMLS is one of the established metal powder-based 3D printing technologies commercially used for customized DC and implants for human dentistry... 相似文献
816.
Danish Khan Xiaoyuan Liu Geping Qu Amit Ranjan Nath Pengfei Xie Zong-Xiang Xu 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(11):2205926
Perovskite solar cells (PSCs) have grabbed much attention of researchers owing to their quick rise in power conversion efficiency (PCE). However, long-term stability remains a hurdle in commercialization, partly due to the inclusion of necessary hygroscopic dopants in hole transporting materials, enhancing the complexity and total cost. Generally, the efforts in designing dopant-free hole transporting materials (HTMs) are devoted toward small molecule and polymeric HTMs, where small molecule based HTMs (SM-HTMs) are dominant due to their reproducibility, facile synthesis, and low cost. Still, the state-of-art dopant-free SM-HTM has not been achieved yet, mainly because of the knowledge gap between device engineering and molecular designs. From a molecular engineering perspective, this article reviews dopant-free SM-HTMs for PSCs, outlining analyses of chemical structures with promising properties toward achieving effective, low-cost, and scalable materials for devices with higher stability. Finally, an outlook of dopant-free SM-HTMs toward commercial application and insight into the development of long-term stability PSCs devices is provided. 相似文献
817.
Frequency selective surfaces (FSSs) play an important role in wireless systems as these can be used as filters, in isolating the unwanted radiation, in microstrip patch antennas for improving the performance of these antennas and in other 5G applications. The analysis and design of the double concentric ring frequency selective surface (DCRFSS) is presented in this research. In the sub-6 GHz 5G FR1 spectrum, a computational synthesis technique for creating DCRFSS based spatial filters is proposed. The analytical tools presented in this study can be used to gain a better understanding of filtering processes and for constructing the spatial filters. Variation of the loop sizes, angles of incidence, and polarization of the concentric rings are the factors which influence the transmission coefficient as per the thorough investigation performed in this paper. A novel synthesis approach based on mathematical equations that may be used to determine the physical parameters of DCRFSS-based spatial filters is presented. The proposed synthesis technique is validated by comparing results from high frequency structure simulator (HFSS), Ansys electronic desktop circuit editor, and an experimental setup. Furthermore, the findings acquired from a unit cell are expanded to a 2 × 2 array, which shows identical performance and therefore proves its stability. 相似文献
818.
Jitendra Kumar Goyal Shubham Aggarwal Ankit Sachan Pradosh Ranjan Sahoo Sandip Ghosh Shyam Kamal 《Asian journal of control》2023,25(2):769-782
This paper presents the design of output feedback controllers for discrete-time (DT) linear systems. New sufficient LMI conditions are derived for designing static and controllers using decomposition of an auxiliary matrix. The decomposition facilitates linearization of nonlinear term of reduced size to obtain linear matrix inequality criteria. This leads to less conservative results as shown in the numerical examples. In addition, the proposed static output feedback criteria is also used for designing dynamic output feedback controllers for DT systems. Furthermore, a comparative study is also made for the proposed design method with the results existing in the literature. Finally, a DT static output feedback controller is designed for a quarter-car suspension system. Simulation results are provided to show the efficacy of the proposed design method. 相似文献
819.
Ajij Md Pratihar Sanjoy Nayak Soumya Ranjan Hanne Thomas Roy Diptendu Sinha 《Neural computing & applications》2023,35(7):4939-4956
Neural Computing and Applications - Verifying the genuineness of official documents, such as bank checks, certificates, contract forms, bonds, etc., remains a challenging task when it comes to... 相似文献
820.
Aiswarya Samal Anoop Kumar Kushwaha Debashish Das Mihir Ranjan Sahoo Nicholas A. Lanzillo Saroj Kumar Nayak 《Advanced Engineering Materials》2023,25(13):2201192
Copper-graphene (Cu/Gr) composite carries high thermal (κ) and electrical (σ) conductivities compared with pristine copper film/surface. For further improvement, strain is applied (compressive and tensile) and thickness is changed (of both copper and graphene). It is observed that electronic thermal conductivity (κe) and σ enhance from 320.72 to 869.765 W mK−1 and 5.28 × 107 to 23.01 × 107 S m−1, respectively, by applying 0.20% compressive strain. With the increase in copper thickness (three to seven layers) in Cu(111)/single-layer-graphene (SLG) heterosystem, κe increases from 320.72 to 571.81 W mK−1 while electrical resistivity (ρ ∝ (1/σ)) decreases from 0.189 × 10−7 to 0.117 × 10−7 Ωm. Furthermore, with the increase in graphene thickness (one to four layers) in seven-layer Cu(111)/multilayer-graphene (MLG) heterosystem, κe enhances upto 126% while ρ decreases upto 70% compared with the three-layer Cu(111)/SLG. A large available state near Fermi level (of Cu/Gr heterosystem) offers the conduction of more electrons from valence to conduction bands. The increasing thickness broadens this state and enhances conduction electrons. The electron localization function decreases with increasing thickness, suggesting electrons are delocalized at copper-graphene junction, resulting in an increase of free electrons that enhance κe and σ. Herein, it is useful in advancing the thermal management of electronic chips and in applying hybrid copper-graphene interconnects. 相似文献