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In this study, a well-known Weakest Bound Electron Potential Model (WBEPM) was used to determine the exited-state ionization potential of lithium-like elements for different iso-spectrum series such as 1s2 2p1 P1/2, 1s2 3s2 S1/2 , 1s2 3d2 D1/2, 1s2 4s2 S1/2, 1s2 4p2 P1/2, and 1s2 4d2 D1/2 having nuclear charges from Z = 3 to Z = 18. On the other hand, to utilize relativistic correction, Briet-Pauli approximation has also been applied to the ionization potential using a fourth-order polynomial expression in the nuclear charge Z. The deviation within the range of 0.1% has been observed between estimated and experimental values that are quite remarkable. Furthermore, new ionization potentials were proposed for iso-series with Z ranging from 19 to 30.

In this research, we computed transition probabilities, line strength, and oscillator strengths of more than 5000 transitions in C IV. Very few values of these spectroscopic characteristics were previously known and reported. The calculation method, based on a combination of the weakest bound electron model and numerical approximation, shows reliable values because the correlation between known and calculated values is high. The transition probabilities calculated in this work are compared with known values of the NIST database and those found in literature, and a reasonably good agreement has been observed. The lifetime of Rydberg levels ns, np, nd, nf, ng has been reported up to n = 25. A general sixth-degree polynomial was developed, generating C IV lifetimes with reasonable accuracy. Most of the results presented are new.

Boron is an essential micronutrient necessary for plant growth at optimum concentration. However, at high concentrations boron affects plant growth and is toxic to cells. Aqueous extract of plant-derived smoke has been used as a growth regulator for the last two decades to improve seed germination and seedling vigor. It has been established that plant-derived smoke possesses some compounds that act like plant growth hormones. The present research was the first comprehensive attempt to investigate the alleviation of boron stress with plant-derived smoke aqueous extract on Sorghum (Sorghum bicolor) seed. Smoke extracts of five plants, i.e. Cymbopogon jwarancusa, Eucalyptus camaldulensis, Peganum harmala, Datura alba and Melia azedarach each with six dilutions (Concentrated, 1:100, 1:200, 1:300, 1:400 and 1:500) were used. While boron solutions at concentrations of 5, 10, 15, 20 and 25 ppm were used for stress. Among the dilutions of smoke, 1:500 of E. camaldulensis significantly increased germination percentage, root and shoot length, number of secondary roots and fresh weight of root and shoot while, boron stress reduced growth of Sorghum. It was observed that combined effect of boron solution and E. camaldulensis smoke extract overcome inhibition and significantly improved plant growth. Present research work investigated that the smoke solution has the potential to alleviate boron toxicity by reducing the uptake of boron by maintaining integrity of plant cell wall. The present investigation suggested that plant derived smoke has the potential to alleviate boron stress and can be used to overcome yield losses caused by boron stress to plants.