One-step synthesis of bifunctional iron-doped manganese oxide nanorods for rechargeable zinc–air batteries

2019 ◽  
Vol 9 (5) ◽  
pp. 1245-1254 ◽  
Author(s):  
Ankita Mathur ◽  
Aditi Halder

Iron doped MnO2 nanorods are successfully synthesized via one step hydrothermal method. The nanorods shows remarkable high bifunctional electrocatalytic activity for oxygen reduction as well as oxygen evolution reaction. For practical applications, a solid-state zinc–air battery was made for powering a light emitting diode.

Author(s):  
Yan Zhang ◽  
Yanjie Liang ◽  
Shihai Miao ◽  
Dongxun Chen ◽  
Shao Yan ◽  
...  

A series of Cr3+-doped BaMSi3O9 (M = Zr, Sn, Hf) near-infrared emitting phosphors with tunable luminescence properties have been successfully synthesized by using a simple solid-state reaction method. The developed...


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3886
Author(s):  
Arwa Almusa ◽  
António H.S. Delgado ◽  
Paul Ashley ◽  
Anne M. Young

The of this study aim was to develop a rapid method to determine the chemical composition, solvent evaporation rates, and polymerization kinetics of dental adhesives. Single-component, acetone-containing adhesives One-Step (OS; Bisco, USA), Optibond Universal (OU; Kerr, USA), and G-Bond (GB; GC, Japan) were studied. Filler levels were determined gravimetrically. Monomers and solvents were quantified by comparing their pure Attenuated Total Reflectance-Fourier Transform Infra-Red (ATR–FTIR) spectra, summed in different ratios, with those of the adhesives. Spectral changes at 37 °C, throughout passive evaporation for 5 min, then polymerisation initiated by 20 s, and blue light emitting diode (LED) (600 mW/cm2) exposure (n = 3) were determined. Evaporation and polymerisation extent versus time and final changes were calculated using acetone (1360 cm−1) and methacrylate (1320 cm−1) peaks. OS, OU, and GB filler contents were 0, 9.6, and 5.3%. FTIR suggested OS and OU were Bis-GMA based, GB was urethane dimethacrylate (UDMA) based, and that each had a different diluent and acidic monomers and possible UDMA/acetone interactions. Furthermore, initial acetone percentages were all 40−50%. After 5 min drying, they were 0% for OS and OU but 10% for GB. Whilst OS had no water, that in OU declined from 18 to 10% and in GB from 25 to 20% upon drying. Evaporation extents were 50% of final levels at 23, 25, and 113 s for OS, OU, and GB, respectively. Polymerisation extents were all 50 and 80% of final levels before 10 and at 20 s of light exposure, respectively. Final monomer polymerisation levels were 68, 69, and 88% for OS, OU, and GB, respectively. An appreciation of initial and final adhesive chemistry is important for understanding the properties. The rates of evaporation and polymerisation provide indications of relative required drying and light cure times. UDMA/acetone interactions might explain the considerably greater drying time of GB.


Author(s):  
Xin Yu Gao ◽  
Xingwei Sun ◽  
Jia Hui Guo ◽  
Ya Nan Teng ◽  
Lei Liu ◽  
...  

The exploration of bifunctional oxygen electrode towards oxygen evolution reaction (OER) activity and oxygen reduction reaction (ORR) is the bottlenecks for the development of rechargeable zinc-air battery as a clean...


1974 ◽  
Vol 20 (9) ◽  
pp. 1135-1137 ◽  
Author(s):  
R Fesler ◽  
Th Clerbaux

Abstract A small, easily-built photometer is described, in which a solid-state light-emitting diode is used as the light source and a phototransistor as the detector. The detector response is kept constant by modulating the diode intensity in proportion to the absorption characteristics of the sample being analyzed. Linearity and stability are good, even with turbid solutions (drift is <0.001 absorbance unit per hour). A typical application of this photometer is the continuous measurement of the percentage of oxyhemoglobin (0 to 100 %) in blood. For hemoglobin concentrations from 3 to 18 g/dl, the relation between oxyhemoglobin as estimated with this diode photometer and by a galvanic method (LEX-O2-CON) was: SO2LED = 0.993 SO2 % LEX + 0.69;r = 0.9975; n = 129; Syx = 1.59.


RSC Advances ◽  
2016 ◽  
Vol 6 (86) ◽  
pp. 82824-82831 ◽  
Author(s):  
Hua Yu ◽  
Degang Deng ◽  
Youjie Hua ◽  
Chenxia Li ◽  
Shiqing Xu

An emission-tunable phosphor, Eu2+-activated LiSr(4−x−y)Cax(BO3)3:yEu2+ phosphor, was synthesized by high temperature solid state reaction.


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