第七章碳杂重键的加成(Addition to Carbon -HeteroMultiple Bonds) 一.反应机理 碱催化机理 酸催化机理 二.羰基活性 1.底物 电子效应 空间效应 2.亲核试剂 试剂的亲核性的强度 试剂的可极化度大小 空间效应

Two Kinds of Underlying Assets · Investment assets: held for investment purposes by a significant numbers of investors. Examples: stocks, bonds, gold. Three different situations: 1. The asset provides no income 2. The asset provides a known dollar income 3. The asset provides a known dividend yield Consumption assets: held primarily for consumption. Examples: commodities such as copper, oil and live hogs

oissue: bring out (esp. sth. printed and /or official) for the notice of the public发布,发行 -----The school issued a statement about its plans to the press. ---th newsletter(简报) is issued three times a year. -----The Ministry of Finance has decided to issue new government bonds(债券)