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91.
92.
Sudipta BISWAS Satadru PRAMANIK Suman MANDAL Sudeshna SARKAR Sujata CHAUDHURI Swati DE 《材料科学前沿(英文版)》2020,14(1):24
Asymmetric patchy Ag/Cu Janus nanoparticles (NPs) were synthesized via a “seed-mediated” approach. This is the first report of synthesis of nanometer sized metal-based Janus NPs without using complicated methods. Selective adsorption of the surfactant onto the seed NPs leads to the formation of Janus type structure. Subsequently the reduction potential of Ag+/Ag0 and Cu2+/Cu0 systems directs the formation of the “patch”. The patchy Janus NPs show significant antifungal activity towards a potent rice pathogen thus offering the prospect of future application in crop protection. 相似文献
93.
Guilherme Ferreira Sumita Goswami Suman Nandy Luis Pereira Rodrigo Martins Elvira Fortunato 《Advanced functional materials》2020,30(5)
Sustainable and safe energy sources combined with cost effectiveness are major goals for society when considering the current scenario of mass production of portable and Internet of Things (IoT) devices along with the huge amount of inevitable e‐waste. The conceptual design of a self‐powered “eco‐energy” smart card based on paper promotes green and clean energy, which will bring the zero e‐waste challenge one step closer to fruition. A commercial raw filter paper is modified through a fast in situ functionalization method, resulting in a conductive cellulose fiber/polyaniline composite, which is then applied as an energy harvester based on a mechano‐responsive charge transfer mechanism through a metal/conducting polymer interface. Different electrodes are studied to optimize charge transfer based on contact energy level differences. The highest power density and current density obtained from such a paper‐based “eco‐energy” smart card device are 1.75 W m?2 and 33.5 mA m?2 respectively. This self‐powered smart energy card is also able to light up several commercial light‐emitting diodes, power on electronic devices, and charge capacitors. 相似文献
94.
Sourav Banerjee Akash Chowdhury Swastik Mukherjee Utpal Biswas 《Automatic Control and Computer Sciences》2018,52(3):208-219
Cloud computing is one of the most emerging technologies which has created a revolution in the High performance Computing (HPC) domain. The term Quality of Service (QoS) plays a vital role in the formation of more flexible integration of various technologies. The Waiting Time (WT), Turnaround Time (TAT), Context Switching (CS) and Makespan (MS) are the primary parameter that has great impact on the scheduling of cloudlets. The Proposed algorithm has improved the resource utilization system of the existing Round Robin Algorithm (RRA) and Improved Round Robin Cloudlet Scheduling Algorithm (IRRCSA) by introducing the concept of dynamically calculated Time Quantum (TQ) for each virtual machine (VM) according to the allocated cloudlets. This new approach in cloudlet scheduling drastically reduced average WT, average TAT and Number of CS of the VMs, which further enhanced the capability of cloud service providers (CSPs) to provide better QoS. 相似文献
95.
Sourav Mandal Susanne Meininger Uwe Gbureck Bikramjit Basu 《Journal of materials science. Materials in medicine》2018,29(3):29
One of the important aspects in 3D powder printing (3DPP) is the selection of binder for a specific material composition to produce scaffolds with desired microstructure and physico-chemical properties. To this end, a new powder-binder combination, namely tetracalcium phosphate (TTCP) and phytic acid (IP6) was investigated at ambient temperature, for low load bearing application. A minimal deviation (<200?µm, w.r.t. computer aided design) was observed in the final sample through optimization of 3DPP process, along with minimum strut and macro-pore size of 200 and 750?µm, respectively. Importantly, the printed scaffolds exhibited compressive strength of 4–8.5?MPa (in the range of cancellous bone) and in vitro dissolution experiments in phosphate buffered saline (PBS) upto one month revealed gradual degradation in strength property. The TTCP scaffolds are characterized to be moderately porous (~40%) with high interconnectivity, which is essential for vascularization and good osteoconductivity. Another major aim of this study was to demonstrate the failure mechanism of 3D powder-printed scaffolds using monotonic and intermittent compression coupled with micro-computed tomography (µCT) imaging. Analyzing these results, we have demonstrated the origin of crack generation and propagation under compressive loading in relation to the unique microstructure, obtained through 3DPP. These findings enable us to acquire a deeper insight of the relationship between structural attributes and failure behavior, to further tailor the 3D powder printing process for ceramic biomaterials. 相似文献
96.
Suman Rani Neetu Ahlawat Kanta Maan Sangwan Sunita Rani R. Punia Jaideep Malik 《Journal of Materials Science: Materials in Electronics》2018,29(13):10825-10833
High performance dielectric materials are highly required for practical application for energy storage technologies. In this work, high-k pristine and modified calcium copper titanate having nominal formula Ca0.95Nd0.05Cu3Ti4?xZrxO12 (x?=?0.01, 0.03 & 0.10) were synthesized and characterized for structural and dielectric properties. Single phase formation of the synthesized compositions was confirmed by X-ray diffraction patterns and further analysed using Rietveld refinement technique. Phase purity of the synthesized ceramics was further confirmed by Energy-dispersive X-ray Spectroscopy (EDX) analysis. SEM images demonstrated that grain size of the modified CCTO ceramics was controlled by Zr4+ ions due to solute drag effect. Impedance spectroscopy was employed to understand the grain, grain boundaries and electrode contribution to the dielectric response. Nyquist plots were fitted with a 2R-CPE model which confirms the non-ideality of the system. Substitution of specific concentration of Nd and Zr improved the dielectric properties of high dielectric permittivity (ε′ ~?16,902) and minimal tanδ (≤?0.10) over a wide frequency range. The giant ε′ of the investigated system was attributed to internal barrier layer capacitance (IBLC) effect and reduced tanδ accredited to enhanced grain boundaries resistance due to substitution of Zr4+ ions at Ti4+ site. 相似文献
97.
Kumari Suman Anas Mohd. Raghav D. S. Chauhan Shital Siwach P. K. Malik V. K. Singh H. K. 《Journal of Superconductivity and Novel Magnetism》2022,35(11):3225-3240
Journal of Superconductivity and Novel Magnetism - YBa2Cu3O7-δ/La1-x-yPrxCayMnO3 (YBCO/LPCMO) (x?~?0.31, y?~?0.35) bilayers with fixed ferromagnetic layer thickness... 相似文献
98.
Sourav Banerjee Mainak Adhikari Utpal Biswas 《Service Oriented Computing and Applications》2017,11(1):65-73
Cloud computing offers the proficiency to use computing and storage resources on a metered basis and reduces the investments in Information Technology domain. This paper highlights a major research issue, i.e., providing good quality of service (QoS) to the cloud users. The QoS is associated with several parameters such as completion time, response time, turnaround time (TAT), waiting time (WT), bandwidth. A new cloudlet scheduling algorithm—improved round robin cloudlet scheduling algorithm—has been proposed which improves the TAT, WT and number of context switching. It enhances the resource utilization. The experimental results are obtained by CloudSim toolkit extending few base classes and compared by classical round robin algorithm. 相似文献
99.
Vaijinath S. Kamanna Howard A. I. Newman Suman T. Patel Ahsok K. Tehim Donald T. Witiak Dennis R. Feller 《Lipids》1989,24(1):25-32
Influence of clofibrate and an aci-reductone, 4-(4-chlorophenyl)-2-hydroxytetronic acid (CHTA) on lipoproteins and apoproteins
was studied in cholesterol- plus cholic acid-fed rats. CHTA (0.4 mmol/kg body wt, twice daily) significantly lowered serum
total cholesterol and triglyceride concentrations at both 10 and 16 days, whereas clofibrate at the same dose did not alter
serum cholesterol levels, but elevated serum triglyceride concentrations at 16 days. The abnormal cholesterol-rich very low
density lipoproteins (VLDL), intermediate density lipoproteins (IDL) and low density lipoproteins (LDL) produced by cholesterol
plus cholic acid were significantly reduced in their cholesterol content by treatment with CHTA, a compound having an oxidation
reduction potential. Conversely, clofibrate administration increased VLDL-cholesterol with concomitant decreases in IDL- and
LDL-cholesterol concentrations. Administration of CHTA to cholesterol- plus cholic acid-fed rats significantly increased concentrations
of VLDL and IDL, but had no effect on HDL protein. Both CHTA and clofibrate administration to cholesterol- plus cholic acid-fed
rats significantly lowered IDL protein concentrations.
Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) studies of apoproteins revealed that clofibrate treatment
significantly reduced apoC-III and C-II in VLDL, C-II in IDL, and apoA-IV and A-I in HDL. Rats treated with CHTA significantly
raised apoC-II and C-III in HDL.
Isoelectric focusing (IEF) of VLDL apoproteins showed a significant decrease in apoC-II, C-III-0 and apoC-III-3 in clofibrate-treated
animals. Thus, the mechanism for antilipidemic action of the oxidation reduction compound, CHTA, which differs markedly from
the prototype drug, clofibrate, is independent from major apoprotein modification. 相似文献
100.
Suman Jangra Bharti Sharma Rahul Jangra Vinod Chhokar Surender Duhan 《Journal of Porous Materials》2018,25(4):945-953
In this study, first time a nanoformulation, saponin-loaded SBA-15 has been developed for an improved and continuous release. The SBA-15 nanopowder was synthesized by a hydrothermal process. Saponin was introduced into the mesoporous channels of SBA-15 and its concentration in SBA-15 was measured by UV–visible spectrophotometry. The pristine SBA-15 and saponin-loaded SBA-15 were characterized by small-angle XRD, FESEM, HRTEM, TGA, FTIR. N2 adsorption–desorption isotherms were used to measure the specific surface area and pore channel structure parameters of pristine and loaded SBA-15. Saponin release was studied in phosphate buffered saline (pH 7.4), which revealed that the release rate could be effectively controlled. The controlled drug release is highly desired for cancer treatment. The cytotoxicity of pristine and loaded SBA-15 was analyzed on Panc-I cancer cells. Both the pristine SBA-15 and saponin-loaded SBA-15 nanoparticles showed specific toxicity on the cancer cells. The preliminary results showed that saponin-loaded SBA-15 could be an effective therapeutic agent for Panc-I cancer cells. 相似文献