硫酸

Several mixed control samples of manganic manganous oxide, manganese dioxide and manganese sulfate with various sulfur content were prepared by adding sulfuric acid with known concentration into high pure manganic manganous oxide. Then they were dried and mixed, and the content of sulfur was determined by high frequency infrared ray carbon sulfur analyzer.

向高纯四氧化三锰中加入已知浓度的硫酸，制备不同含硫量的四氧化三锰、二氧化锰、硫酸锰的混合物控制样，将制备好的控制样干燥、混匀后，用高频红外碳硫分析仪分析控制样中的硫含量。

Using manganous sulfate(MnSO4) as raw material,ammonium hydrogen carbonate(NH4HCO3) as precipitating agent and sodium dodecyl sulfate as particle size controller and through the process of quick addition of MnSO4 and NH4HCO3 solutions at same time,monodisperse submicron manganous carbonate(MnCO3) spherical particles were prepared by controlling suitable reaction crystallization conditions.

以硫酸锰为锰源，碳酸氢铵为沉淀剂，十二烷基硫酸钠为粒径控制剂，采用硫酸锰和碳酸氢铵两种溶液快速同时加入的方式，通过控制合适的反应结晶条件，制备出亚微米级单分散球形碳酸锰颗粒。借助扫描电镜、X射线衍射、粒度分析仪等研究了反应结晶条件对碳酸锰粒径和形貌的影响。

In this article, anthrone-sulfuric method and phenol-sulfuric method were used to test quantificationally Medicago sativa polysaccharides content, and made sure which one is the better method.

采用蒽酮－硫酸法和苯酚－硫酸法测定了苜蓿芽多糖含量，并比较了2种方法的适用性。

As for acetalation, we research the effects of acid kinds, acid quantity, temperature solvents on it and get the conclusions that the optimized acid is sulfuric acid, the optimized temperature is 65 °C, the reaction time is five hours, and the material ratio of sulfuric acid to methylglyoxal to methanol is 0.028:1:6.837.

在醛保护一步中，研究了酸种类、酸用量、温度及其溶剂的影响，得到了本反应的较好条件是：酸为浓硫酸，反应温度为65℃，反应时间为5小时，浓硫酸：丙酮醛：甲醇的配比为0.028：1：6.837，反应收率可达81%。

Using the improved method, the standard molal enthalpies of solution ＝－29.18 kJ·mol－1 in pure water and ＝－25.79 kJ·mol－1 in aqueous sulfuric acid were obtained, respectively.

借助VOSO4水溶液的离子缔合平衡和硫酸的二级解离平衡，改进了Archer方法，并用这种改进的方法分别估算了VOSO4·2.76H2O在水中的标准摩尔溶解焓＝－29.18 kJ·mol－1，以及在0.5 mol·kg－1硫酸水溶液中的标准摩尔溶解焓＝－25.79 kJ·mol－1。

Myristic monoethanolamide ammonium sulfatewas synthesized from myristic acid and monoethanolamide with sulfamic acid as sulfating agent .

在芳烃类溶剂与羰基化合物催化剂存在下，以肉豆蔻酸和乙醇胺为原料，氨基磺酸作硫酸化剂，制备了肉豆蔻酸单乙醇酰胺硫酸酯铵盐。

In order to solve these problems, first, activated carbon which was deashed by hydrochloride was modified through using concentrated sulfuric acid, concentrated nitric acid, hydrogen peroxide and potassium permanganate in the paper, the result showed that the modification of activated carbon is best through using concentrated sulfuric acid under 250℃ through analyzing the desulfurization efficiency and acidic oxygenous group on surface.

对上述问题，本文首先采用浓硫酸、浓硝酸、双氧水和高锰酸钾等氧化剂对盐酸脱灰后的活性炭进行化学改性，通过对改性活性炭的脱硫效果及其表面酸性含氧基团分析，得出在250℃的温度下采用浓硫酸改性活性炭效果最好。

In order to improve the electro-catalytic activity of platinum based catalyst to methanol oxidation, in this thesis, firstly prepare heteropoly acid modified Pt/GC electrode with different concentration by cyclic voltammetry method, and then test the cyclic voltammetry curves individually in vitriolic and methanol solution. The study shows the best concentration for both phosphomolybdic acid and phosphotungstic acid is 1×10~(-3)mol/L. And find the more heteropoly acid modified on electrode, the lower peak-up potential towards methanol because of the existence of oxygenous species.

为了改善铂基催化剂氧化甲醇的催化活性，本论文首先通过循环伏安扫描法制备了不同浓度磷钼酸和磷钨酸修饰的Pt/GC电极，通过研究Pt/GC电极在修饰前后在硫酸溶液中及含甲醇的硫酸溶液中的循环伏安行为发现，磷钼酸和磷钨酸均能在PtRu/C电极上发生氧化还原反应，而且杂多酸修饰浓度对Pt/GC电极氧化甲醇的催化活性有很大影响。

Ferric sulfate and sulfuric acid was used to catalyze the conversion of palmitic acid to methyl esters.

棕榈酸制备生物柴油采用酸催化法，比较了硫酸和硫酸铁两种催化剂的效果。

The result indicated that: the amount of the excess HF formed direct ratio to the yield of phosphorus pentafluoride and the optimum amount of the excess HF used is about 35%; the trickling rate of oleum shouldnt make the temperature of hexafluorophosphoric acid exceed 25 ℃ and the amount of oleum is 110% to 125% that of stoichiometry so that the content of phosphorus pentafluoride can be achieved 90%; the time and temperature of heating hexafluorophosphoric acid influenced both the yield and the content of phosphorus pentafluoride, and the optimum time should be about 30 minutes and the proper temperature was 148 to 153℃; when alcohol used asrefrigerant, the content of phosphorus pentafluoride was 94.03%, and the content can be up to 97.38%, provided that using liquid nitrogen as refrigerant.

通过实验发现，氟化氢用量与五氟化磷的产率成正比，最佳过量百分率宜在35％左右；发烟硫酸的滴加速度不能使中间产物温度大于25℃，发烟硫酸用量大于理论量10％～25％时，得到的五氟化磷纯度高于90％；六氟磷酸的加热温度对五氟化磷的产率和纯度均有影响，宜在148～153℃的范围内，加热时间应在30分钟左右；用工业酒精做冷凝介质得到的五氟化磷纯度最高只能到达94.03％，使用液氮做冷凝介质可以使五氟化磷的纯度达97.38％以上。

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％。