It seems that new scientific discoveries nearly always bring to mankind a blessing. It is the new scientific discoveries that bring human beings from primitive caves gradually to cozy and comfortable dwelling houses, from shabby cotton clothes to various good-quality wearing apparel, from simple food to various kinds of nutritious foods. It is the new scientific discoveries that change people's ways of living, make people communicate more easily and broaden mankind's vision to the global village. Indeed, new scientific discoveries have fundamentally changed our earth and greatly improved living standard of the inhabitants on it.