钒酸

The kinetic parameters of vanadium catalytic oxidation of azomethine H by bromate have been determined by using spectrophotometric method .

以酸性介质中痕量钒催化溴酸钾氧化甲亚胺 H显色反应为对象，利用光度法研究了反应的动力学参数。

In the work, three P-Mo-V heteropoly acids with different Vanadium number have been synthesized by acidification- etherization. Their component and structure have been confirmed by ICP-AES and TGA. They have been characterized by FT IR, XRD and UV. FT IR demonstrates their Keggin structure.

本文采用酸化—醚化法合成了三种不同钒原子数的P-Mo-V三元杂多酸，并用ICP-AES和TGA确定其化学组成和结构，用FT IR、XRD和UV等手段对其结构和性质进行了表征。

Iron is recovered in the form of jarosite and ferric hydroxide that the concentrations of them determinate with dichromate method are

其中铁以黄铁钒和氢氧化铁的形式回收利用，经GB/T 223.7-2002重铬酸钾滴定法滴定其铁含量分别为72.37％，62.0％己达到可综合利用的水平。

The mechanism of vanadium removal from ammonium molybdate solution by ion-exchange was studied.

摘 要：对钼酸盐溶液离子交换钼钒分离机理进行研究。

This paper introduces the use of vanadium-ammonium molybdate colorimetric method to estimate the phosphorus content in the manganese ore.

用钒—钼酸铵比色法测定锰矿中的磷含量，测定结果表明：相对偏差小于 2 %，测定范围 0 1～ 1 0 %方法简便快速，可满足生产要

Mixed-addenda heteropolyacid ; catalysis ; 2-octanol ; hexa noic acid

磷、钼、钒多元杂多酸；催化作用；仲辛醇；己酸

Phosphorus in the sample reacts with the vanadomolybdate/ammonium molybdate reagent and a bright yellow colour is formed.

样品中的磷与钼酸亚钒/钼酸铵反应形成亮黄色。

Methods:Vanadium was determined by dual-wavelength catalytic spectrophotometric method which was based on the vanadium catalyzing oxidation of acridine orange and acid chrome blue K by potassium bromate in 0.010 mol/L H2SO4 medium.

在硫酸介质中，利用钒催化溴酸钾氧化吖啶橙和酸性铬蓝K褪色反应，分别在476 nm和556 nm处测量催化体系和非催化体系的吸光度的变化，用双波长催化光度法测定痕量钒。

The net cement with bentonite can form hydrogen key which can improve the felt of the systematic and are wail for eventual strength; The main mechanism of J-85 accelerator to accelerate concrete coagulating are in alkalescence condition to make aluminate and gypsum link and block the building of calcium and aluminium sulphate around cement granule; Polypropylene acid can improve early strength of cement through altering the thickness of hydroxide in cement grout.

添加膨润土后的水泥净浆中形成了氢键，提高了体系的粘结性，对后期强度发展有利； J-85速凝剂加速混凝土凝结的主要机理就是在碱性条件下，使铝酸盐和石膏结合，阻碍水泥颗粒周围的硫铝酸钙即钙钒石的生成，从而使水泥迅速凝结；聚丙烯酸通过改变水泥浆体中羟基的浓度从而提高水泥试块初期强度。

The conversion and selectivity of oxidation of 2-octano l to hexanoic acid by nitric acid using the mixed-addenda heteropolyacid H15- xPMoxV12-xO40·nH2O(n=20-40)as the catalys t were studied.

采用磷、钼、钒系列多元杂多酸作为硝酸氧化仲辛醇制己酸的催化剂，对其催化性能和选择性进行了实验研究。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。