Zaheer Uddin

New even and odd parity levels of neutral praseodymium

The hyperfine (hf) structure of some spectral lines of the praseodymium atom has been investigated by the laser-induced fluorescence method in a hollow cathode discharge lamp. We report the discovery of 18 new energy levels of even parity and 22 new energy levels of odd parity and their magnetic dipole hf interaction constants A. Using these newly discovered levels, 268 lines were classified by means of laser spectroscopy, 97 of them by laser excitation and 171 via laser-induced fluorescence. In addition, 23 lines, observed in a Fourier transform spectrum, were classified by means of their wavenumbers and their hf patterns.

Determination of Weibull Parameter by Four Numerical Methods and Prediction of Wind Speed in Jiwani (Balochistan)

In this paper we determine the Weibull parameters (k and c) using four methods. Method of Moments, Empirical Method, Energy Pattern Method and Maximum likelihood Method have been employed to determine and compare the values of k and c. The daily wind speed data (obtained from Karachi Meteorological office) of Jiwani (Balochistan, Pakistan) town over a period of 10 years (1998-2007) is used to estimate the Weibull parameters. The mean wind speed was predicted using k and c by four methods. A significant agreement is found in measured and predicted mean wind speed.

Investigation of Pr I lines by a simulation of their hyperfine patterns: discovery of new levels

Hyperfine structure (hf) patterns of unclassified spectral lines of the praseodymium atom, as appear in a high-resolution Fourier transform spectrum, have been simulated. In this way, the J-values and hf constants of the levels involved in the transitions were determined. Assuming that so far only one unknown level is participating in the transition, these constants were used to identify the known level. The second unknown level was found by performing subtraction or addition of the wave number of the transition to the wave number of the known level. The existence of the new level was then checked by explaining other unclassified lines with respect to the wave number and the hf pattern. In this way, 19 new levels of the praseodymium atom were discovered and are presented in this paper. In some cases, the accuracy of the hf constants was improved by laser-induced fluorescence spectroscopy.

Laser Spectroscopic Investigations of Praseodymium I Transitions: New Energy Levels

We report the discovery of about 140 new energy levels of the neutral praseodymium atom, found by means of laser-induced fluorescence spectroscopy. Their energy has been determined with an uncertainty of 0.010 cm−1 using a wave number calibrated Fourier-transform spectrum.

Comparison of Wind Energy Potential for Coastal Locations: Pasni and Gwadar

A comparative study for the wind power density of the two investigated coastal sites viz. Pasni and Gwadar is presented in this paper. Pasni and Gwadar are located along the coast belt of Balochistan in Arabian Sea. Investigations are performed on daily wind speed data recorded at 12:00 UTC, obtained from Pakistan Meteorological Department (PMD) for a period five years, i.e. from 2003 to 2007. The recorded wind speed data distribution is fitted to the Weibull distribution function described by two fitting parameters i.e. scale (c) and shape (k). The Weibull parameters are numerically calculated using the Method of Moment (MoM). Monthly mean wind speeds for the two stations are predicted and wind power densities are calculated for the two stations. Comparison of the wind power densities of the investigated sites reveals a higher wind energy yield for Pasni as compared to Gwadar. The highest wind power density is predicted for the month of May.

New Odd Levels of Pr I with Low Angular Momentum

Ten new odd levels, of praseodymium I (Pr I), having angular momentum less than 3.5, have been discovered through Fourier transform spectroscopy and presented in this paper. The discovered levels not only explain previously known lines, but also explain some new lines of Pr I. All the new levels together explain fifty-six atomic lines. Previously known classifications of two of the lines of Pr are incorrect, new classifications of these lines have been suggested.

An Initial Tidal Power Resource Estimation at Jhari Creek of Indus Delta, Sindh, Pakistan

Energy crisis in Pakistan is one of the severe challenges the country is facing today. Electricity is essential part of our daily life and its shortage has severely affected the economy and the other segments of society. This shortfall of electricity is increasing day by day and situation becomes worst especially in summer. The energy crisis are caused due to disproportionate dependence on non-renewable energy resources. The most effective solution that has been found to overcome such crisis is the use of tidal energy, because tidal energy has a significant advantage over many other forms of renewable energy as it is almost perfectly predicted over long time horizons. Therefore, first time an attempt has been made to estimate the tidal energy resources at Jhari creek of Indus Delta, Sindh, Pakistan. For this purpose real time tidal data is acquired from Pakistan Navy and tidal resources are estimated. Potential power density is calculated for the duration of four months May-August 2013 and found that highest potential mean spring power density was observed in June 2013 that was 1.67 W/m 2 .

Estimation of Diffuse Solar Radiation from Clearness Index for Multan, Southern Punjab, Pakistan

Empirical correlations have been developed for Multan for the estimation of Diffuse Solar Radiation (DSR) as a function of clearness index (K T ). The diffuse solar radiation are also estimated by the relationship as given by Liu and Jorden, Page and Iqbal. All these correlation shows a peak value of diffuse solar radiation for the months of July & August (monsoon months). The diffuse to global (total) radiation ratio is 0.317. The presently developed correlation are fine agreement with the result obtained by earlier models. It is inferred from the result that solar energy has bright prospects as far as its application and utilization is concerned.