الفهرس 
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Abstract
The main aim of this work is to prepare sodium borate glasses which contain substantial amounts of copper oxide reached to 25 mol%. The CuO is added frequently to glass at the expense of Na2O with concentration ranged between 0–25 mol%. Up to specific CuO concentration (22.5 mol%), the obtained glasses are transparent and free from crystals of precipitated copper oxide. The added CuO can possess some useful advantages to borate glasses; for example, it lowers the coefficient of thermal expansion of the investigated materials and increases its hardness. It was found that the desirable borate glass can dissolve a relatively high concentration of CuO which reaches 25 mol%. Under some circumstances, the hardness is cautiously increased with increasing the Cu/Na ratio, since the increase of the CuO and decrease Na2O content results in reducing the expansion coefficient of the glass and increasing the hardness number of the investigated glasses.The NMR structural investigation, using the advantages of 23Na and 11B magnetic resonances, has revealed that CuO acts mainly as an intermediate (network former and modifier). CuO has the priority to be modified by Na2O, compared with B2O3, to yield CuO4 groups. Therefore, the concentration of the modified copper is increased at the expense of the modified BO4 species. Hence, the concentration of the BO4 is therefore decreased with increasing CuO/Na2O molar ratio.