substituent

简明释义

英[sʌbˈstɪtjʊənt]美[sʌbˈstɪtʃʊənt]

adj. 被代替的；可代分子的

n. 取代基；取代者

英英释义

单词用法

同义词

反义词

例句

1.The absorption, emission maximum and the fluorescence lifetime changed as the Hammett substituent constant in folding linear.

最大吸收、最大发射、及荧光寿命与取代基的哈密顿取代基常数呈折线关系。

2.Furthermore, the migration ability of substituent of ketone had a significant impact on selectivity.

同时，迁移集团的迁移能力也对反应的选择性有很大的影响。

3.The healthy soy sauce was produced with mixed strain fermentation through using oat and residual biomass of beer substituent for soybean powder.

对以燕麦和啤酒废弃生物质替代部分豆粕为原料，利用混合菌种发酵酿造保健酱油进行了研究。

4.Excellent selectivity was obtained for the separations of polar position isomers. The benzamide substituent group on crown ether makes the stationa…

由于冠醚上引入苯甲酰胺取代基，因而对苯胺类及不经衍生化的碱性化合物能特殊选择性地分离。

5.In this paper, the correlations of the formation of dimers with solvent polarity, concentration, nature of substituent group and central metal were investigated.

本文探讨了有关二聚体的形成与溶剂极性、溶液浓度、取代基团性质及络合金属原子的关系。

6.The results show that the formation of dimers depends on the nature of substituent group, dielectric constant of solvent, and concentration.

结果表明二聚体的形成取决于取代基团的性质以及溶剂的介电常数与溶液浓度。

7.The presence of a methyl substituent 取代基 can influence the boiling point of the compound.

甲基取代基的存在可以影响化合物的沸点。

8.The reactivity of the compound can change based on the nature of the substituent 取代基 attached.

化合物的反应性可以根据附加的取代基的性质而变化。

9.Different substituents 取代基 can lead to different isomers in a chemical compound.

不同的取代基可以导致化学化合物中的不同异构体。

10.In organic chemistry, a substituent 取代基 can significantly alter the properties of a molecule.

在有机化学中，一个取代基可以显著改变分子的性质。

11.When analyzing the reaction, we must consider each substituent 取代基 on the aromatic ring.

在分析反应时，我们必须考虑芳香环上的每个取代基。

作文

In the field of chemistry, understanding the concept of a substituent is crucial for analyzing molecular structures and their reactivity. A substituent refers to an atom or group of atoms that replaces a hydrogen atom in a hydrocarbon chain or ring. This replacement can significantly alter the chemical properties and behavior of the molecule. For instance, in organic chemistry, when we examine aromatic compounds, the presence of different substituents on a benzene ring can lead to various reactions and products. Each substituent has its own unique characteristics that influence the overall properties of the compound. To illustrate this, let’s consider the case of toluene, which is essentially a methyl group (-CH3) attached to a benzene ring. Here, the methyl group acts as a substituent. When we introduce different substituents, such as nitro (-NO2) or amino (-NH2) groups, we can observe changes in the reactivity of the toluene. The presence of a nitro group, for example, makes the compound more electrophilic, thereby increasing its susceptibility to nucleophilic attack. This transformation is vital in synthetic organic chemistry, where chemists often manipulate substituents to achieve desired outcomes in reactions. Moreover, the positioning of substituents on a benzene ring can lead to ortho, meta, or para substitution patterns, each with distinct chemical implications. Understanding these patterns is essential for predicting the behavior of molecules in various chemical reactions. The study of substituents extends beyond simple hydrocarbons; it encompasses complex biological molecules as well. For instance, in pharmaceuticals, the effectiveness of a drug can often be traced back to the specific substituents present in its structure. By modifying these substituents, chemists can enhance the drug's efficacy or reduce side effects, demonstrating the practical importance of this concept in real-world applications. In summary, the role of substituents in chemistry cannot be overstated. They are fundamental components that not only define the structure of molecules but also dictate their chemical behavior and reactivity. Whether in academic research or industrial applications, a thorough understanding of substituents allows chemists to innovate and create new compounds with tailored properties. As we continue to explore the vast world of chemistry, the significance of substituents will undoubtedly remain a pivotal focus, guiding our understanding of molecular interactions and the development of new materials and drugs. Thus, mastering the concept of substituents is essential for anyone aspiring to excel in the field of chemistry, as it lays the groundwork for further exploration and discovery. In conclusion, the term substituent (取代基) plays a vital role in the comprehension of chemical structures and reactions. By studying how different substituents interact within molecules, we gain invaluable insights into the nature of chemical reactivity and the design of new compounds. This knowledge is not only academically enriching but also practically applicable in various scientific and industrial fields, making it an indispensable part of the chemistry curriculum.

在化学领域，理解取代基的概念对于分析分子结构及其反应性至关重要。取代基指的是在烃链或环中替代氢原子的原子或原子团。这种替代可以显著改变分子的化学性质和行为。例如，在有机化学中，当我们研究芳香化合物时，苯环上不同的取代基的存在可能导致各种反应和产物。每个取代基都有其独特的特性，影响化合物的整体性质。为了说明这一点，让我们考虑甲苯的例子，甲苯本质上是一个甲基（-CH3）附着在苯环上。在这里，甲基作为一个取代基。当我们引入不同的取代基，如硝基（-NO2）或氨基（-NH2）时，我们可以观察到甲苯的反应性发生变化。例如，硝基的存在使得化合物更具亲电性，从而增加了其对亲核攻击的敏感性。这种转变在合成有机化学中至关重要，化学家们常常操纵取代基以实现反应中的预期结果。此外，取代基在苯环上的位置可以导致邻位、间位或对位取代模式，每种模式都有不同的化学意义。理解这些模式对于预测分子在各种化学反应中的行为至关重要。取代基的研究不仅限于简单的烃；它还涵盖复杂的生物分子。例如，在制药行业，药物的有效性往往可以追溯到其结构中具体的取代基。通过修改这些取代基，化学家们可以增强药物的疗效或减少副作用，这表明这一概念在现实应用中的重要性。总之，取代基在化学中的作用不可低估。它们不仅定义了分子的结构，而且决定了它们的化学行为和反应性。无论是在学术研究还是工业应用中，彻底理解取代基使化学家能够创新并创造具有特定性质的新化合物。随着我们继续探索广阔的化学世界，取代基的重要性无疑将继续成为一个关键焦点，引导我们理解分子相互作用以及新材料和药物的开发。因此，掌握取代基的概念对于任何希望在化学领域取得成功的人来说都是必不可少的，因为这为进一步探索和发现奠定了基础。最后，术语取代基在理解化学结构和反应中发挥着至关重要的作用。通过研究不同的取代基在分子中的相互作用，我们获得了对化学反应性及新化合物设计的宝贵见解。这一知识不仅在学术上令人振奋，而且在各个科学和工业领域中具有实际应用，使其成为化学课程中不可或缺的一部分。