一硝酸酯

The method is characterized in that the acid solution of one of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid and hydriodic acid is divided into two portions; aniline monomer and ammonium persulfate are respectively added; then aniline monomer solution and ammonium persulfate solution can be prepared.

一种乙酸松油酯的制备方法，其特征是，将盐酸、硫酸、硝酸、磷酸、氢碘酸中任一种酸溶液分成两等份，并分别加入苯胺单体和过硫酸铵，形成苯胺溶液和过硫酸铵溶液。

Isosorbide mononitrate is a drug used principally in the treatment of angina pectoris and acts by dilating the blood vessels ao as to reduce the blood pressure.

单硝酸异山梨酯是一种主要用于治疗心绞痛的药物，通过扩张血管来降低血压。

Compounds 3a-3d, 4a-4d, 5a-5d, 6a-6e and 7a-7e were prepared with a new efficient method, in which the aromatic amines were diazotized with isoamyl nitrite in EtONa/EtOH under refluxing condition, and mono -, bis -and tetrakis -substituted calix [4] arenes were obtained respectively as main product by diazo-coupling in different molar ratio to calix [4] arene.

一，提出了一个有效的新方法合成含有芳香偶氮基团的杯[4]芳烃衍生物3a-3d；4a-4d；5a-5d；6a-6e和7a-7e：即在非水溶剂乙醇中用亚硝酸异戊酯，在强碱乙醇钠存在下对芳香胺进行重氮化，得到芳香重氮酸盐沉淀，过滤，然后加入杯[4]芳烃的四氢呋喃溶液，通入CO〓气体调节溶液的pH值为7-9，使其发生偶联反应。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。