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Nazmul Abedin Khan Biswa Nath Bhadra Suk Woo Park Yong‐Su Han Sung Hwa Jhung 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(12)
Polyanilines (pANIs), loaded with phosphotungstic acid (PTA), are pyrolyzed to get WO3 or W2N (≈6 and ≈7 nm, respectively), which is well‐dispersed on pANI‐derived porous carbons (pDCs). Depending on the pyrolysis temperature, WO3/pDC, W2N/pDC, or W2N‐W/pDCs could be obtained selectively. pANI acts as both the precursor of pDC and the nitrogen source for the nitridation of WO3 into W2N during the pyrolysis. Importantly, W2N could be obtained from the pyrolysis without ammonia feeding. The obtained W2N/pDC is applied as a heterogeneous catalyst for the oxidative desulfurization (ODS) of liquid fuel for the first time, and the results are compared with WO3/pDC and WO3/ZrO2. The W2N/pDC is very efficient in ODS with remarkable performance compared with WO3/pDC or WO3/ZrO2, which is applied as a representative ODS catalyst. For example, W2N/pDC shows around 3.4 and 2.7 times of kinetic constant and turnover frequency (based on 5 min of reaction), respectively, compared to that of WO3/ZrO2. Moreover, the catalysts could be regenerated in a facile way. Therefore, W2N/pDC could be produced facilely from pyrolysis (without ammonia feeding) of PTA/pANI, and W2N, well‐dispersed on pDC, can be suggested as a very efficient oxidation catalyst for the desulfurization of liquid fuel. 相似文献
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Pattern Analysis and Applications - Rare association rule mining is an imperative field of data mining that attempts to identify rare correlations among the items in a database. Although numerous... 相似文献
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Rewari Sonam Nath Vandana Haldar Subhasis Deswal S. S. Gupta R. S. 《Microsystem Technologies》2019,25(5):1537-1546
Microsystem Technologies - In this paper a cylindrical Dual Metal (DM) Dielectric Engineered (DE) Gate All Around (GAA) MOSFET has been proposed to resolve a big issue of Gate Inducted Drain... 相似文献
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This investigation deals with laser remelting of plasma sprayed alumina and chromia coatings. The time-temperature history of the laser remelted zone was recorded using an infrared pyrometer during the remelting operation. Cooling rates, under varying scanning speed, were determined from the time temperature curve. Surface morphology, microstructure, and phases of the laser treated and as-sprayed coatings were characterized using scanning electron microscopy, optical microscopy, X-ray diffraction, respectively. X-ray diffraction was also employed to measure the surface residual stress of the coatings. Inherent features of plasma sprayed coatings like porosity and inter-lamellar boundary were obliterated upon laser remelting. A columnar grain growth perpendicular to the laser scanning direction was observed. The range of roughness of the as-sprayed coatings reduced from 6 to 8?µm to 1–2?µm in the remelted layers. For both coatings, more than 90% reduction in porosity was found upon laser remelting. Surface residual stress of the as-sprayed alumina and chromia coatings was found to be tensile and compressive, respectively. Within the limits of the testing condition the tensile residual stress of the remelted layers increased by up to around 500% in the alumina coatings. In the chromia coating a decrease of compressive stress by up to around 80% was recorded. In the remelted layer the tensile nature of the stress showed a tendency to increase with an increase in the cooling rate. However, the state of stress of the as-sprayed layer, i.e., tensile or compressive, was retained in the remelted layer. The residual stress was found to decrease in the remelted layer with an increase in the degree of overlap of the remelted tracks. 相似文献
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Mandal Pratap Chandra Mukherjee Imon Chatterji Biswa Nath 《Multimedia Tools and Applications》2021,80(3):3623-3644
Multimedia Tools and Applications - Data hiding is a noteworthy research topic in digital technology for years. Reversible data hiding (RDH) technique plays a vital role for confirming security of... 相似文献