上标

Diels-Alder reaction between β-myrcene and maleic anhydride catalyzed by SO(superscript 2- subscript 4)/TiO2-ZrO2 solid superacid was investigated.

研究了SO(上标 2-下标 4)/TiO2-ZrO2型固体超强酸催化剂的制备及其催化β-月桂烯与马来酸酐的Diels-Alder反应，通过GC、GC-MS和红外分析，确定其主产物为4-（4-甲基－3-戊烯基）－4-环己烯-1，2-酸酐。

Octadecyl acrylate was synthesized by melt esterification from octadecyl alcohol and acrylic acid using solid super acid as catalyst.

以丙烯酸和十八碳醇为原料，采用固体超强酸SO(上标 2-下标 4)-/TiO2为催化剂及直接酯化法制备丙烯酸十八酯。

The EMPA results indicate that the main chemical compositions of the "Lvlongjing" sampe are SiO2 and MgO, followed by Al2O3 and FeO, and the chemical formula is calculated and projected to be in the area of penninite according to Fe(superscript 2+)/R(superscript 2+) and atomicity of Si.

电子探针结果表明，该&绿龙晶&样品的主要化学成分为SiO2和MgO，其次为Al2O3和FeO；计算其晶体化学式并根据Fe(上标 2+)/R(下标 2+)和Si的原子数量进行投影，恰好落于叶绿泥石的区域范围。

Pentaerythrityl tetraacetate was synthesized from acetic acid and pentaerythrite, catalyzed by SO(superscript 2- subscript 4)/TiO2-La2O3 rare-earth solid superacid. Various factors affecting the reaction were discussed.

以稀土固体超强酸SO(上标 2-下标 4)/TiO2-La2O3为催化剂，乙酸和季戊四醇为原料合成季戊四醇四乙酸酯，并考察了影响反应的因素。

SO(superscript 2- subscript 4)-TiO2/γ-Al2O3 solid superacid catalyst has good catalytic activity in the synthesis of other acetals.

SO(上标 2-下标 4)-TiO2/γ-Al2O3新型固体超强酸催化剂在其它缩醛的合成中也具有良好的催化活性。

In this paper, the dissents in groundwater analytical data from a ministerial professional laboratory during 1991 to 2000 were summarized. The factors resulting in the dissents, their characteristics and causes, as well as prevention measures were discussed. During the 10 years, dissents of 12 parameters including H2SiO3, Sr, NO2(superscript -), I(superscript -), SO(superscript 2- subscript 4) and etc. were found and most of the parameters are very important in research of hydrogeology, hydro-geochemistry, groundwater environment and groundwater exploration.

通过对国土资源部某专业实验测试中心10年质量异议资料的分析，总结了地下水水质检测中容易产生质量异议的检测参数，分析了这些参数的特点，探讨了质量异议产生的原因和预防措施。1991~2000年间该实验室共有H2SiO3、Sr、NO2、I、SO(上标 2-下标 4)等12项检测参数出现质量异议，大多为水文地质、水文地球化学、地下水环境质量研究和地下水开发利用所关心的关键参数。

OBJECTIVE To study the effects of aloe-emodin and emodin on scavenging superoxide anion free radical O(superscript – subscript 2 and hydroxy free radical.

目的：研究芦荟大黄素和芦荟素对超氧阴离子自由基O(上标–下标 2、羟自由基的清除作用。

Aloe-emodin and emodin have strong clearing function on O(superscript – subscript 2) and OH, and the clearance is obviously related to the concentration.

芦荟大黄素、芦荟素对O(上标–下标 2)、OH均有较强清除能力，且清除能力与浓度呈明显的量效关系。

Br(superscript -) and NO3(superscript -) have a stronger inhibitory effect on the photolytic decoloration of direct sky blue than SO(superscript 2- subscript 4), NO2(superscript -) and Cl(superscript -). The coexistence of two different anions has a synergistic inhibition effect on the photolysis decoloration.

与SO(上标 2-下标 4)、NO2、Cl相比BR和NO3对脱色作用抑制最显著，而且两者能形成协同作用抑制光解脱色。

Fe2O3/SO(superscript 2- subscript 4) solid super acid was obtained by dissolving iron nitrate in ammonia, dipping the resultant iron hydroxide in sulfuric acid, filtration and calcination.

硝酸铁溶于氨水得到Fe3后再用硫酸浸泡，经过滤、焙烧制得固体超强酸催化剂Fe2O3/SO(上标 2-下标 4)。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。