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981.
In this communication, new composite desiccant materials having 37% concentration of CaCl2 have been compared for water production from atmospheric air. The vermiculite–saw wood, jute and burnt-clay have been used as host materials and CaCl2 as a hygroscopic salt. All the desiccant materials have been tested with the solar glass desiccant box type system (SGDBS) with a collector area of 0.36?m2. Design parameters for water production are: height of the glass from the desiccant bed to be 0.22?m, an inclination angle of 30°, the effective thickness of the glass as 3?mm and the number of glazing is single. It has been found that on the experimental day, the maximum amount of fresh water generated by the vermiculite–saw wood/CaCl2 is 130?ml/kg/day.  相似文献   
982.
Energy demand is the hot topic of all developing and developed countries. Energy demand has been increasing day by day at a high rate. So, it is necessary to find an alternative solution that is eco-friendly. Biodiesel can be the alternative solution for this problem. The main purpose of this paper is to test the engine performance and emission parameters of a diesel engine using pure cinnamon oil blended with diesel and using cerium oxide as a catalyst. The parameters measured are brake power, brake thermal efficiency, specific fuel conception, CO2, CO, NOx and HC.  相似文献   
983.
A series of Er~(3+) ions doped lithium lead alumino borate(LiPbAlB) glasses were synthesized via melt quench method and their structural,physical and optical properties were studied.Judd-Ofelt theory in correlation with the emission and absorption profiles was performed for the measurement of various radiative parameters for different transitions of Er~(3+) doped glasses.The as-prepared glasses show deep green(550 nm) as well as NIR(1532 nm) emission at 380 and 980 nm excitation wavelengths,respectively.The intensity of emission spectra increases with Er~(3+) ions concentration up to 1.5 mol% and beyond quenching is observed.The Dexter theory applied to the emission profiles reveals the interaction between Er~(3+)ions as dipole-dipole in nature.CIE color coordinates are found to fall in the green region of the visible spectrum.It is observed that 1.5 mol% of Er~(3+) ions concentration is optimum to exhibit the maximum quantum efficiency,branching ratios,gain bandwidth,emission cross-section,gain crosssection and aptly suitable for visible and NIR photonic applications.  相似文献   
984.
985.
LnPO4 · 0.667H2O rhabdophane has been considered as a potential material for the precipitation of actinides from radioactive waste liquid, owing to its outstanding characteristics of high actinide bearing and easy synthesis in acid solutions. However, a comprehensive understanding of the actinide occupation and the precipitation response of rhabdophane to remove actinides has yet to be established. In this study, the effect of ions concentration and pH values on the detailed precipitation reaction of CexNd1-xPO4 · 0.667H2O rhabdophane in acid solutions are systematically investigated. Some specific issues such as structural distortion and flexibility, and occupation mechanism are discussed by combining with experiments and density functional theory (DFT) calculation. The results reveal that ions concentration and pH values have a significant impact on the crystallization nucleation step before 12 h. The obtained removal rate of Nd3+ is more than 99% in pH 1–5 solutions with the ions concentration of 0.05–0.1 mol/L. Moreover, incorporating Nd in CePO4 · 0.667H2O rhabdophane will easily result in the lattice distortion in b-axis. DFT calculation and X-ray photoelectron spectroscopy (XPS) results reveal that Nd is preferentially incorporated in nonhydrated site to form a weaker binding energy of NdO8 polyhedron.  相似文献   
986.
Multilayer solar selective absorber coatings have been developed in the last few decades. The thermal stability in terms of microstructure gives an insightful understanding of the optical properties of such coatings. In this context, we extensively utilized transmission electron microscopy (TEM) analysis to establish the thermal stability of TiB2/Ti(B,N)/SiON/SiO2 coating, under thermal cycling/continuous heating to 500°C in vacuum for 250 h. In particular, this work reports the variation in the solar absorptance of TiB2/Ti(B,N)/SiON/SiO2 coating with different angles of incidence of the solar radiation. Extensive analysis using the TEM technique reveals the presence of oxide interlayers that act as diffusion barrier layers to enhance the thermal stability of the coating. Computational simulation using SCOUT software validates the measured reflectance spectrum of the developed multilayer coating. The minor changes in absorptance and emissivity after heat treatment in vacuum at 500°C, together with high solar absorptance over a broad angular variation, establish the potential application of TiB2/Ti(B,N)/SiON/SiO2 as a selective coating in concentrated solar power systems.  相似文献   
987.
SnO2-coated TiNb2O7 powders were synthesized via the solution coating method in the present research. The SnO2 layers with a thickness of 3–5 nm were homogeneously coated on the surface of TiNb2O7 particles. TiNb2O7 coated with SnO2 of 5 mol% with high Li+ diffusion coefficient delivered the discharge capacity of 319.5 mAh/g, which was 6.6% higher than that of the non-coated samples. The enhancement of capacity for the coated TiNb2O7 was owing to the low charge-transfer resistance of 17.5 Ω in contrary to the non-coated TiNb2O7 (27.8 Ω). SnO2-coated TiNb2O7 possessed an improved capacity retention of 85.2% at 5 C after 100 cycles, superior to the non-coated TiNb2O7 (79.8%). On the other hand, the excessive amounts of SnO2 coating led to the reduction in the capacity of the prepared samples. The excessive amounts of SnO2 layers suppressed the Li+ diffusion and increased the charge-transfer resistance. The obtained results in this study indicated that coating of TiNb2O7 with appropriate amounts of SnO2 significantly improved the electrochemical performance of TiNb2O7.  相似文献   
988.
Pal  Shaili  Kumar  Ajay  Kumar  Sunil  De  Arup Kumar  Prakash  Rajiv  Sinha  Indrajit 《Catalysis Letters》2022,152(11):3259-3271
Catalysis Letters - Magnetically recyclable visible light photocatalysts for the degradation of critical organic pollutants are an urgent industrial requirement. Nonetheless, one component...  相似文献   
989.
Devi  Neena  Patel  Sanjay K. S.  Kumar  Pradeep  Singh  Archana  Thakur  Nandita  Lata  Jeevan  Pandey  Deepak  Thakur  Vikram  Chand  Duni 《Catalysis Letters》2022,152(4):944-953
Catalysis Letters - In this study, Rhodococcus pyridinivorans cells containing hyperactive acyltransferase was immobilized on various macromolecules based-polymeric matrices and used to improve...  相似文献   
990.
Journal of Inorganic and Organometallic Polymers and Materials - We serendipitously designed one novel 1D hetero-binuclear Zn(II)-Pb(II) coordination polymer, namely...  相似文献   
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