Preparation of polyacrylonitrile-based activated carbon fiber for CS2 adsorption

Research on Chemical Intermediates - Polyacrylonitrile (PAN)-based activated carbon fiber (ACF) was prepared by CO2 and KOH activation method, respectively, and used for the adsorption of CS2 at...     

Thermodynamic analysis of an ejector–vapour compressor cascade refrigeration system

Using the framework of the first and second law of thermodynamics, an ejector–vapour compressor cascade refrigeration system is studied. The criteria for refrigerant selection are examined, with R134a and R410A selected as the refrigerant for the ejector and compressor sub-cycle, respectively. The effects of generator temperature, evaporator temperature, condenser temperature, intercooler temperature and intercooler temperature difference are examined. The results demonstrate that a combined cycle can improve 30.8% when compared to the COP of single compressor cycle and 122% when compared to the single ejector cycle. In addition, intercooler temperature can be set at 26.5 °C for minimizing total exergy loss.

     

Salicyaldehyde-based fluorescent sensors with high sensitivity for amino acids

Structurally simple salicylaldehyde-based fluoreseent sensors for amino acids have been obtained by one-step or two-step synthesis.These sensors show significant fluorescence enhancement in the presence of many amino acids at concentrations as low as 10~5 mol/L.The reversible reaction of the aldehydes with amino acids to form imines in aqueous solution is proposed to account for the observed fluorescence enhancement.     

Effects of size and location of distal tear on hemodynamics and wave propagation in type B aortic dissection

Applied Mathematics and Mechanics - The type B aortic dissection (TBAD) is a perilous disease with high morbidity and mortality rates. The hemodynamics of TBAD in different scenarios has been...     

Probing interfacial interactions of nafion ionomer: Thermal expansion of nafion thin films on substrates of different hydrophilicity/hydrophobicity

Interfacial interactions of Nafion ionomer with superhydrophilic (Pt, Au), hydrophilic (SiO₂), and hydrophobic (graphene, octyltrichlorosilane [OTS]‐modified SiO₂) is investigated, using in situ thermal ellipsometry, by quantification of substrate‐ and thickness‐dependent thermal properties of the ultrathin Nafion films of nominal thickness ranging 25–135 nm. For sub‐50 nm thin Nafion films, the thermal expansion coefficient of films decreased in the order of most hydrophobic to most hydrophilic substrate: OTS > graphene > SiO₂ > Au > Pt, implying weaker interpolymer and polymer–substrate interactions for films on hydrophobic substrates. Expansion coefficient of films on SiO₂, graphene, and OTS‐modified SiO₂ decreased with thickness whereas that of films on Au and Pt substrates increased with thickness. Above ~100 nm of thickness, films on all substrates converged toward a common value representative of bulk Nafion. Thermal transition temperature was found to be higher for films on hydrophilic SiO₂ than that for films on hydrophobic graphene and OTS‐modified SiO₂ but was not discernible for films on Au and Pt substrates. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 343–352     

Efficient Pyrazolo[5,4-f]quinoxaline Functionalized Os(II) Based Emitter with an Electroluminescence Peak Maximum at 811 nm

Upon fusing the pyrazinyl pyrazole entity in giving pyrazolo[3,4-f]quinoxaline chelate, the corresponding Os(II) based NIR emitter exhibited “invisible” and efficient electroluminescence with a peak maximum at 811 nm. A maximum external quantum efficiency of 0.97 % and a suppressed efficiency roll-off till a current density of 300 mA cm⁻² was also exhibited.