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New synthesized borosilicate glass system within the molar percentages 50 B2O3 - (14-X) SiO2 - (20+X) Li2O-15 Na2O-1Al2O3 with X=0, 1, 2, 3, 4, 5 mol % was investigated. The amorphous identity of the samples has been checked by X-ray diffraction (XRD). The decrease of the molar volume (Vm) with increasing Li2O amount led to an increase in the calculated oxygen packing density (O.P.D). The packing density of the specimens increased also with the inclusion of Li2O. The Fourier transform infrared (FTIR) showed the transformation of BO3 to BO4 units that increased the rigidity of the prepared glass series. The ultrasound wave velocities (longitudinal (vl) and shear (vs)) were assigned by the pulse-echo technique. Both (vl ) and ( ps ) increased with increasing Li2O content because of increasing the rigidity of the glass host. The elastic Longitudinal (L), Young's (E), Bulk (B) and Shear (S) moduli besides the Micro-hardness (H) were calculated and all increased with increasing Li2O content. Ultrasonic mean velocity (vmean) and softening temperature (Tsm) increased while Poisson's ratio (σm) decreased with the same gradient of X. The theoretical model proposed by (Makishima-Mackenzie) and bond compression model were employed for the prepared glasses. The results from both models showed correspondence with the experimentally obtained values. The impedance spectroscopy was applied to investigate the electrochemical mode of the present glass system and to measure the conductance for all the system samples. [ABSTRACT FROM AUTHOR]

The article reports on the prevalence of neural tube defects (NTD) among babies delivered at Omdurman Maternity Hospital in Khartoum, Sudan. According to the authors, between February 2003 and January 2004, there were 64 babies born with open NTDs. The authors report that delivery of babies with open NTDs remain a significant problem in the country.