In the analytical expression of the PEMFC polarization curve, Eq. (16) , the independent variables are the current density, the temperature and the pressure, while the dependent variable is the voltage. Moreover there are a few constants, that usually are called parameters, and some of these are often unknown.
In particularly cold areas, Trachelospermum jasminoides is best grown in patio containers of loam based compost, such as John Innes No.2, that can be moved to a protected position over winter. Provide the twining stems with an appropriate support such as trellis, wires or a free standing climbing frame.row star jasmine plants in frost-free conditions until large enough to plant outdoors. When they are well grown, plant Trachelospermum jasminoides in fertile, well drained soil in sun or semi-shade. Choose a sheltered position that is protected from cold winter winds.
Alice Aks - CA, Zone 9. After reading all of the above, I was going to mention temperature changes. Here in my colder climate, I get some red rose petals that have that black edge on them. Most of the time it is due to a light frost that gets on the roses on some cold evenings. The edges of the petals get frost bitten and look black and disfigured a bit. How heavy a frost and the timing can cause more of the black edges too. Stan the Roseman Bearrose1954 - Colorado, Zone 5.