次磷酸次磷酸

Points, calculate the MOLARITIES of hydrochloric and phosphoric acids in the

从样品的体积以及第一次和第二次等当点的差异，计算样品中氢氯酸和磷酸

In order to obtain reasonable processing parameter of electroless nickel plating, the influences of the concentration of reductants NaH_2PO_2 and complex agents DL-lactic acid, stabilizers ,pH value and temperature on the deposition rate , the content of P and stability of the plating solution were studied.

在化学镀镍的工艺中，研究了次亚磷酸钠和络合剂乳酸的浓度、pH值、稳定剂和温度等工艺参数等对沉积速度和镀镍层含磷量的影响，找出了合理的化学镀镍工艺：还原剂的浓度为25 g/l~ 30g/l，络合剂乳酸的浓度为8ml/l ~ 12 ml/l，pH值的范围为4.6 ~ 4.9，选择作稳定剂，温度为85℃左右。

The cross-coupling reaction of DOPO with halogenated phenols were achieved for the first time, novel phenolic hydroxyl-containing reactive-type DOPO-based flame retardants used in epoxy resins were synthesized; the cross-coupling reactions of 2\'-hydroxybiphenyl-2-ylphosphinic acid or diphenyl phosphine oxide with halogenated phenols were studied according to the above result, new reactive-type flame retardants used in epoxy resins were synthesized.

采用Pd催化的方法首次实现了DOPO与卤代酚的交叉偶联，合成了新型含酚羟基的反应型DOPO基环氧树脂阻燃剂；在此基础上实现了2-(2-羟基苯基)苯基次磷酸和二苯基氧化膦与卤代酚的偶联，合成了新型反应型有机磷环氧树脂阻燃剂。

On the basis of electroplating and immersion plating tin, and through large numbers of experiments, a new process of electroless plating tin in acid chloride bath solutions including SnCl2 2H2O, NaH2PO2 H2O, special complexing agent, additive agent, stabilizing agent and antioxidant, was established.

本文是在电镀锡、浸镀锡工艺配方的基础上，通过大量的试验，确立了一种以氯化亚锡、次亚磷酸钠和特定的络合剂、添加剂、稳定剂，抗氧化剂为基本镀液组成的酸性氯化物化学镀锡体系，成功地在铜上实现了锡的连续自催化沉积，获得了性能优异的半光亮银白色锡镀层。

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。