China 
Africa 
Explore chapters and articles related to this topic
Capillary Electrophoresis
Published in Grinberg Nelu, Rodriguez Sonia, Ewing’s Analytical Instrumentation Handbook, Fourth Edition, 2019
Zwitterionic buffers such as Bicine, Tricine, CAPS, MES, and Tris are used particularly for protein and peptide separations. Some buffers, such as MES, Tricine, and glycylglycine, bind calcium, manganese, copper, and magnesium ions. Metal binding may be useful, or it may interfere with the subsequent separations. The advantage of the zwitterionic buffer is low conductivity when the buffer is adjusted to its pI. This provides for low current draw and reduced Joule heating, allowing higher buffer concentrations to be used. High buffer concentrations are sometimes useful to minimize interaction between the solute and the capillary wall. Alternatively, high field strengths can be used to speed up the separation. Mobility matc hing between the BGE and sample has been proposed to improve the peak symmetry when the sample concentration is high [11].
Some physiological characteristics to estimate species potential as a mine reclamation ground cover
Published in International Journal of Mining, Reclamation and Environment, 2019
Eddy Nurtjahya, Jennifer A. Franklin
The pH of mine spoils can be widely variable, and while spoils below a pH of 5 are often treated to increase pH, the treatment of high pH spoils is more difficult and revegetation may rely on the selection of tolerant plant species. To test the influence of pH on germination, seeds were germinated on Whatman filter paper in 9-cm sterile plastic Petri dishes, using 50 seeds per dish. The paper was moistened with 3–6 ml of solution at pH 5, 6, 7, 8, 9, 10 or deionised water as a control. Because the upper pH limits for germination are not known for these species, a pH up to 10 was used to ensure the identification of the upper limit of each species range. A 2 mM solution of MES [2–(N–morpholino) ethanesulphonic acid] was adjusted to pH 5 or 6 with 1 N NaOH. A 2 mM solution of HEPES [N–2–hydroxymethyl) piperazine–Nʹ – (2–ethanesulphonic acid)] was adjusted to pH 7 or 8 with 1 N NaOH. A pH 9 or 10 buffer was prepared with 2 mM tricine [N–tris(hydroxymethyl) methylglycine] and adjusted with 1 N NaOH. Petri dishes were sealed with parafilm and placed in a growth chamber with a 12-h temperature cycle of 25 °C/35 °C, a 24-h photoperiod with lighting provided by cool white fluorescent bulbs. Germination was determined by the emergence of radicle, and was assessed every 2–3 days. At each assessment period seeds with radicles emerged were counted and removed and the dish was sealed and returned to the chamber until no further germination was recorded between one assessment period and the next. This test assessed only germination, and establishment was assessed in the greenhouse tests. The experimental design was completely randomised with one factor (pH) and was composed of three replicate dishes for each species and pH treatment.