Delta bilirubin (B delta), isolated from serum, has an absorption maximum near 440 nm and a molar absorptivity of 72,000 L mol-1cm-1 in either Tris HCl (0.1 mol/L, pH 8.5) or phosphate (0.13 mol/L, pH 7.4) buffer. This absorptivity exceeds by approximately 50% and 59%, respectively, that of unconjugated bilirubin in the same buffers. This finding suggests that substantial errors can be incurred...

An extraction-spectrophotometric method for the determination of trace amounts of ammonium ion is described. Ammonium ion is effectively extracted as a neutral ternary complex NH . DB 18C6. calmagite at pH 3.0 into chloroform, followed by spectrophotometric determination at =48 5 nm. Molar absorptivity of the ternary complex at this wavelength is 1.08 10 mol cm . Beer's law is obeyed over...

A simple and sensitive extractive- spectrophotometric method for thedeterrnination of trace amounts of vanadium(V) is reported. The method is based on the quantitative extraction of the anion complex of V(V) with 4-(2-pyridy1azo)-resorcinol with tetrabutylammonium perchlorate into chloroform, followed by spectrophotometric measurements at 554 nm. Beer's law is obeyed over the concentration ...

Fluid dynamics models for laser material processing with metal fusion in conduction mode generally assume a constant absorptivity. This parameter is known to govern the process. However, it used be pre-set by extrapolating absorptance measurements made at different conditions or adjusted reproduce experimental bead shapes. In this study new approach developed. It consists predicting as function...

Abstract Self-ignition coal gangue (SCG) used as one of precursors to fabricate autoclaved aerated concrete (AAC). Aiming at studying water absorptivity and frost resistance performance SCG-based AAC (SCGAAC), three-period absorption tests freeze-thaw were carried out the corresponding results recorded analyzed. In order modify SCGAAC, foam stabilizer was applied adjust pore structure while cal...

Organic aerosol (OA) emissions from wildfires across the western United States have significant impacts on climate and air quality. Brown carbon (BrC)—the light-absorbing component of OA—has been at the...

Perfect metamaterial absorbers have attracted researchers’ attention in solar energy harvesting and utilization. An ideal absorber should provide high absorption, be ultra-wideband, insensitive to polarization incident angles, which brings challenges research. In this paper, we proposed optimized an ultra-wideband based on Ti-Al2O3 cross elliptical disk arrays obtain the absorption of energy. T...