Preheat the oven to 350 degrees F (175 degrees C). Grease a 9×5-inch loaf pan. Stir flour, baking powder, nuts, and salt together in a bowl.
Beat 1 cup sugar and butter together in a separate large bowl until fluffy; beat in eggs one at a time. Stir in 1/2 cup orange juice and orange zest. Pour in flour mixture, and stir until moistened; transfer into prepared loaf pan.
Bake in the preheated oven until a toothpick inserted into the center of the loaf comes out clean, about 1 hour. Remove loaf from oven, but not from pan.
Combine 1/2 cup orange juice with 1/4 cup sugar in a small saucepan. Heat and stir to dissolve sugar. Spoon glaze over hot loaf. Let stand in pan for 10 minutes before removing loaf to a rack to cool.