Semiempirical calculation of van der Waals coefficients for alkali-metal and alkaline-earth-metal atoms

The van der Waals coefficients, C-6, C-8, and C-10 for the alkali-metal (Li, Na, K, and Rb) and alkaline-earth-metal (Be, Mg, Ca, and Sr) atoms are estimated by a combination of ab initio and semiempirical methods. Polarizabilities and atom-wall coefficients are given as a diagnostic check, and the lowest order nonadiabatic dispersion coefficient, D-8 and the three-body coefficient, C-9 are also presented. The dispersion coefficients are in agreement with the available relativistic many-body perturbation theory calculations. The contribution from the core was included by using constrained sum rules involving the core polarizability and Hartree-Fock expectation values to estimate the f-value distribution

Interaction Potentials for He-F- and Ne-F-

[[abstract]]Ab initio potential energy curves for the interaction of a fluoride anion with a He atom and a Ne atom are obtained by supermolecular CCSD(T) calculations, that is, coupled cluster calculations in the space of single and double substitutions corrected noniteratively for triple substitutions. The computations include full counterpoise corrections and employ large basis sets with bond functions. The CCSD(T) potential energy curves have significantly deeper wells than their many-body perturbation theory counterparts. Fits to functional forms that reproduce the CCSD(T) points with an average absolute error less than 0.3% are reported. � 1998 American Institute of Physics

Analysis of an economic order quantity and reorder point inventory control model for Siba group of companies in Utu Ikot Ekpenyong Ikot Ekpene, Akwa Ibom state-Nigeria

As a result of today’s uncertain economy, Companies are searching for alternative ways to stay competitive. SIBA group has been faced with an ineffective forecasting method that has led to multiple product stock outs. The issue faced has caused sales loss as well as profit loss,. This research goes through the process of analyzing the company’s current forecasting model and recommending an inventory control model to help her solve her current issue. As a result, an Economic Order Quantity (EOQ) and a Reorder Point was recommended along with two forecasting techniques to help her reduce her product stock outs. In addition, a cost estimate was done to compare both her current model and the recommended models. As a result, SIBA group, would be able to reduce her overall total cost from ₦1,005,335 to ₦181,155.8. This was a cost reduction of approximately 82 , which summed to a total saving of about ₦836,190 per quarter

The Seroprevalence of Hepatitis B Surface Antigen (HBsAG) and Human Immuno-deficiency Virus (HIV) Among Pregnant Women in Calabar, Cross River State, Nigeria.

The seroprevalence of Hepatitis B surface antigen (HBsAg) and Human Immuno-deficiency Virus (HIV) and their co-infection was investigated among pregnant women in Calabar, Cross River State, Nigeria. Serum samples from 562 pregnant women aged 19-49 years attending antenatal clinics in the University of Calabar Teaching Hospital (UCTH) and the General Hospital (GH) Calabar were tested for HBsAg and HIV using standard proprietory reagents. Thirty –eight (6.8%) of the women were seropositive for HIV; 8(1.4%), for HBsAg and 5(0.9%) for both HIV and HBsAg. Significant infection rates for HBV, HIV and HBV/HIV co-infections were associated with age groups, education, occupation, trimester and parity (P<0.05) of the subjects. The higher seropositivity rates for HIV and HBV co-infection in pregnant women suggests high endemicity in the general population. The need to properly screen, diagnose and effectively treat all pre/post natal women to prevent transmission to others and serious pregnancy outcomes is hereby advocated.Keywords: HBsAg, HIV, Co-infection, Pregnant women, Calabar, Nigeria