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The results showed that the amorphous iron oxide has highly catalytic activity. The intermediate products are pyrocatechin, hydroquinone, benzoquinone and low-grade fatty acid. The mechanism of catalyst oxidation is assumed that the free radical OH attacks benzene cycle at the adjacent position and para-position of OH on phenol so that the benzene cycle is opened and low-grade fatty acid is produced and transformed into CO2 and H2O.

结果表明,非晶铁氧化物催化剂在催化氧化降解苯酚时具有较高的催化活性,苯酚降解的中间产物有:对苯二酚、邻苯二酚、苯醌和低级脂肪酸,其降解机理是羟基自由基攻击苯环上OH的部位或对位而使苯环开环,生成低级脂肪酸,并最终转化成二氧化碳和水,从而使苯酚得以降解。

The study of fluorescence spectrum proved that the excited phenylenerings of amorphous PES copolymer with high density phenylenerings in its main chain could form an excimer with the surrounding unexcited phenylenerings, and the emission peak intensity of excimer was strengthened with the increase of aging time.

荧光光谱的研究证明,非晶态聚醚砜共聚物由于主链苯环密度较高,苯环受激处于激发态时易与周围激态苯环相互作用形成激基缔合物,缔合物发射峰的强度随老化时间增加而增强。

The study of fluorescence spectrum proved that the excited phenylene-rings of amorphous PES copolymer with high density phenylene-rings in its main chain could form an excimer with the surrounding unexcited phenylene-rings, and the emission peak intensity of excimer was strengthened with the increase of aging time.

荧光光谱的研究证明,非晶态聚醚砜共聚物由于主链苯环密度较高,苯环受激处于激发态时易与周围激态苯环相互作用形成激基缔合物,缔合物发射峰的强度随老化时间增加而增强。

So, the aromaticity of acenaphthenyl groups in C_2 gum should be the least. In order to explain the reason, quantum chemical calculation is utilized. The optimized geometrical structrures of condensed aromatics in C_1 gum, C_2 gum and C_3 gum are calculated at B3LYP/6-31G* levels. We find that some phenyl groups in acenaphthenyl groups are coplanar and have the largest conjugated structure.

为了解释其原因,我们利用量子力学方法进行了计算,研究了三种稠环基团在B3LYP/6-31G*基组水平下优化得到的几何结构,发现苊式多苯基苯基中的萘环和中间的苯环共面,电子离域性最大,而其他二者所有苯环都不共面,发生了明显地扭曲;同时,在优化几何结构的基础上,对三种化合物进行了前线分子轨道的分析,利用密度泛函理论方法(density function theory,DFT)计算了稠环基团的最高占有轨道和最低未占轨道之间的能量差,即能隙,发现C_2胶上苊式多苯基苯基的Eg最小,解释了C_2胶具有最好的辐射保护效果的原因。

Understand the mechnism of aromatic electrophilic substitution reactions and the characteristics of the benzonium ion; grasp halogenation, nitration, sulfonation, Friedel-Crafts alkylation and acylation reactions; understand the effect of substituents on reactivity and orientation; know the side-chain reactions of alkylbenzenes and alkenyl benzenes; be familiar with the synthetic methods and application of derivatives of benzene.

了解苯环亲电取代反应机理及苯正离子的特性;掌握苯环卤化、硝化、磺化、Friedel-Crafts 烷基化和酰基化反应及取代效应;了解烷基苯、烯基苯的支链反应和苯衍生物的合成应用。

In order to develop an useful synthestic process, we have synthesized amides with various substitutents. The isoquinoline skeleton was constructed through Bischler-Napieralski reaction, followed by asymmetric reduction of the imine intermediates with a Ru complex to form the only chiral center. Finally, we connected the two phenyl groups by Heck reaction and effectively obtained optically active aporphine alkaloids.

为了发展一套实用的合成方法,我们首先制备於苯环上具有不同种取代基的苯乙醯胺,接著透过Bischler-Napieralski反应进行分子内合环,并利用钌金属对亚胺中间体进行不对称的还原反应,建立出产物中唯一的光学活性中心,最后再利用Heck反应连结两个苯环,就可以顺利得到具有光学选择性的阿朴吩类天然物。

Synthesis process Molecular Formula:〓 Molecular Weight: 394 Chemicla name: N-(2, 3-dihydro-2, 7-dimethyl-benzofuran-1-acyl)-N'-tert-butylN'-(3, 5-dimethyl benzoyl) hydrazine Structural formula:〓 This article define a synthesis method of JS118 with (2, 3-dihydro-2, 7-dimethylbenzofuranyl)-6-formic acid, tert-butyl hydrazine hydrochloride acid and 3, 5-dimethyl benzoic acid as main intermediate through four steps of reaction involving, acyl chloridation condensation and so on.

本文主要的研究工作内容:(1)以N-特丁基双酰肼为先导结构,利用分子等排原理和类同合成法进行先导设计,有目的、有选择地重点改变R〓、R〓基团,将具有不同取代基的苯环以及呋喃环、苯并呋喃环、吡咯环、吡啶环等杂环、稠杂环与先导结构进行有机的组合。

And the ability of antioxidant of polyhydroxy benzamides don't have too many differences with Trolox (IC50 =13.90 μg/ml), the substition of hydroxy group at amino benzene ring doesn't affect the whole ability of antioxidant apparently, but while the single hydroxy group at carboxylic acid benzene ring, they are apparently decrease to scavenge the ability of free radical, as a result, the hydroxy at amino benzene ring substitutes its function, without the hydroxy group, the ability of antioxidant is worst, but it upgrades its function while the hydroxy and amino are in the ortho-position or para-position.

而当多酚醯胺化合物其抗氧化能力与Trolox差不多时(IC50 =13.90 μg/ml),胺基苯环上之羟基取代对整体抗氧化能力影响不明显,但在羧酸苯环上具单羟基时,其清除自由基能力明显下降,使得胺基苯环上羟基取代发挥了影响力,无羟基取代时,抗氧化能力最差,而羟基与胺基互为邻位或是对位时较间位有提升效果。

The results showed that the MS2 fragmentation pathways of DASSSB were affected by the character and position of substitutes on salicylidene phenyl. The C=N cleaving to form fragmentation ion [M+H-283](superscript +) was dominant for DASSSB compounds with electron-donating group on the C4 of the salicylidene phenyl; while fragmentation ion [M+H-254] (superscript +) forming by C-C cleavage of the β-position of C=N was dominant for DASSSB compounds with electron-withdrawing group on the C5 of the salicylidene phenyl.

结果显示,这些化合物的ESI-MS/MS裂解方式与它们分子中水杨醛苯环上取代基的性质和位置有关:当水杨醛苯环上4位连接供电子取代基时,分子以CN双键断裂为主,生成[M+H-283]碎片离子;当水杨醛苯环上5位连接吸电子取代基时,分子以CN双键β位的C-C键发生断裂为主,生成[M+H-254]碎片离子。

The results of calculation will be fundmentally consistent with the experimental values.In addition, we calculated dibenzene chromium and its derivatives, ferroceneand its derivatives. The former had higher symmetry. We studied the substituenteffects by calculating their NMR spectra. The results show that: when we add asubstitute group on one ring of dibenzene chromium, the substitute group will affecttwo benzene rings. The effect is similar to the effect of branched alkanes, namely:the effect on neighbouring groups has transmissibility. Furthermore, the nearer theneighbouring group is, the stronger the effect is. This effect is observed not only onthe substituted ring, but also on the unsubstituted ring.

此外,我们重点计算了二苯铬及其衍生物和二茂铁及其衍生物的核磁共振谱,其中二苯铬及其衍生物选择的是对称性较好的体系,通过计算其核磁共振四川师范大学硕士学位论文谱,探讨其取代基效应,结果表明:在二苯铬的一个环上引入取代基后,取代基对两个苯环的影响,类似于支链院烃引入取代基后的影响:即对邻近基团的影响有传递性,并且对离得近的作用强,对离得远的作用弱,这种作用不仅体现在连有取代基的环上,也体现在没有带取代基的环上。

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推荐网络例句

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称;三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起,称之为挽歌体诗人或者史诗诗人,他们被称为诗人,似乎只是因为遵守格律写作,而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。

This is not paper type of business,it's people business,with such huge money involved.

这不是纸上谈兵式的交易,这是人与人的业务,而且涉及金额巨大。