检索结果-南通市图书馆

Key Role of Some Specific Occupied Molecular Orbitals of Short Chain n-Alkanes in Their Surface Tension and reaction rate constants with Hydroxyl Radicals: DFT Study

引用

International Journal of Organic Chemistry 2021年第1期11卷 1-13页

作者： Mikhail Yu Gorbachev Natalia N. Gorinchoy Ion Arsene Department of Physical and Quantum Chemistry Institute of Chemistry Academy of Sciences of Moldova Kishinev Republic of Moldova

Basing on the DFT calculations we propose the new theoretical model which describes both the surface tension σ of the short chain n-alkanes at their normal boiling points and their reaction rate constants with hydroxyl radicals OH• (at 297 ± 2 K) on the basis of their molecular orbital electronic characteristics. It has been shown that intermolecular dispersion attraction within the surface liquid monolayer of these compounds, as well as their reaction rate constants k with OH• radicals are determined by the energies Eorb of the specific occupied molecular orbitals which are the same in the determination of both the above physico-chemical characteristics of the studied n-alkanes. The received regression equations confirm the theoretically found dependences between the quantities of σ and k and the module |Eorb|. For the compounds under study this fact indicates the key role of their electronic structure particularities in determination of both the physical (surface tension) and the chemical (reaction rate constants) properties.

关键词： Surface Tension reaction rate constants n-Alkanes Hydroxyl Radicals Dispersion Attraction Orbital Controlled Interactions DFT Calculations

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Orbital Nature of Solubility of Shot Chain n-Alkanes in Water and Their reaction rate constants with Nitronium Cations: A DFT Study

引用

International Journal of Organic Chemistry 2022年第2期12卷 92-101页

作者： Mikhail Yu. Gorbachev Natalia N. Gorinchoy Department of Physical and Quantum Chemistry Institute of Chemistry Academy of Sciences of Moldova Kishinev Republic of Moldova

The new theoretical models describe both the solubility S of the shot chain n-alkanes in water at 298.15 K, and their reaction rate constants k with nitronium cation NO2+ at 293.15 K on the basis of their molecular orbital characteristics. It is shown that both the quantities S and k are determined by the energies Eorb of the specific virtual (for S) and occupied (for k) molecular orbitals of these n-alkanes. The obtained regression equations confirm the theoretically found dependences of S and k on the absolute value of Eorb. This fact demonstrates that the electronic structure particularities of the studied n-alkanes play a crucial role in both their above-mentioned physicochemical properties.

关键词： Solubility in Water reaction rate constants n-Alkanes Nitronium Cations Orbital Controlled Interactions DFT Calculations

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Evaluating the effects of granular and membrane filtrations on chlorine demand in drinking water

引用

Journal of Environmental Sciences 2009年第1期21卷 23-29页

作者： Veeriah Jegatheesan Seung Hyun Kim C. K. Joo GAO Baoyu School of Engineering James Cook University Townsville QLD 4811 Australia. Department of Civil Engineering Kyungnam University 631-701 Masan Korea Chilseo Water Treatment Plant Haman 637-940 Korea School of Environmental Science and Engineering Shandong University Jinan 250100 China

In this study, chlorine decay experiments were conducted for the raw water from Nakdong River that is treated by Chllseo Water Treatment Plant （CWTP） situated in Haman, Korea as well as the effluents from sand and granular activated carbon （GAC） filters of CWTP and fitted using a chlorine decay model. The model estimated the fast and slow reacting nitrogenous as well as organic/inorganic compounds that were present in the water. It was found that the chlorine demand due to fast and slow reacting （FRA and SRA） organic/inorganic substances was not reduced significantly by sand as well as GAC filters. However, the treated effluents from those filters contained FRA and SRA that are less reactive and had small reaction rate constants. For the effluents from microfiltration, ultrafiltration, and nanofiltration the chlorine demand because FRA and SRA were further reduced but the reaction rate constants were larger compared to those of sand and GAC filter effluents. This has implications in the formation of disinfection by products （DBPs）. If DBPs are assumed to form due to the interactions between chlorine and SRA, then it is possible that the DBP formation potential in the effluents from membrane filtrations could be higher than that in the effluents from granular media filters.

关键词： chlorine decay model initial concentration nitrogenous compounds organic and inorganic compounds reaction rate constants

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Kinetics and mechanism of titanium hydride powder and aluminum melt reaction

引用

International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 165-172页

作者： Ali Rasooli Mehdi Divandari Hamid Reza Shahverdi Mohammad Ali Boutorabi School of Metallurgy and Materials Engineering Member of Center of Excellence for Advanced Material and Processing (CEAMP) Iran University of Science and Technology Tehran 16844 Iran Department of Materials Faculty of Engineering Tarbiat Modaress University Tehran 14115-143 Iran

Based on the measurement of the released hydrogen gas pressure （PH2）, the reaction kinetics between TiH2 powder and pure aluminum melt was studied at various temperatures. After cooling the samples, the interface of TiH2 powder and aluminum melt was studied. The results show that the-time curves have three regions; in the first and second regions, the rate of reaction conforms zero and one order, respectively; in the third region, the hydrogen gas pressure remains constant and the rate of reaction reaches zero. The main factors that control the rate of reaction in the first and second regions are the penetration of hydrogen atoms in the titanium lattice and the chemical reaction between molten aluminum and titanium, respectively. According to the main factors that control the rate of reaction, three temperature ranges are considered for the reaction mechanism：（a） 700-750°C, （b） 750-800°C, and （c） 800-1000°C. In the first temperature range, the reaction is mostly under the control of chemical reaction; at the temperature range of 750 to 800°C, the reaction is controlled by the diffusion and chemical reaction; at the third temperature range （800-1000°C）, the dominant controlling mechanism is diffusion.

关键词： titanium hydride aluminum reaction kinetics reaction rate constants

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Role of water on the H-abstraction from methanol by ClO

引用

Journal of Environmental Sciences 2018年第9期30卷 89-98页

作者： Shanshan Tang Narcisse T.Tsona Junyao Li Lin Du Environment Research Institute Shandong University Jinan 250100 China

The influence of a single water molecule on the reaction mechanism and kinetics of hydrogen abstraction from methanol （CH3OH） by the CIO radical has been investigated using ab initio calculations. The reaction proceeds through two channels： abstraction of the hydroxyl H-atom and methyl H-atom of CH30H by CIO, leading to the formation of CH30 ＋ HOC1 （＋H20） and CH20H ＋ HOC1 （＋ H20）, respectively. In both cases, pre- and post-reactive complexes were located at the entrance and exit channel on the potential energy surfaces. Results indicate that the formation of CH2OH ＋ HOC1 （＋H20） is predominant over the formation of CH30 ＋ HOC1 （＋H20）, with ambient rate constants of 3.07 x 10^-19 and 3.01 x 10^-23 cm^3/（***）, respectively, for the reaction without water. Over the temperature range 216.7-298.2 K, the presence of water is seen to effectively lower the rate constants for the most favorable pathways by 4-6 orders of magnitude in both cases. It is therefore concluded that water plays an inhibitive role on the CH30H ＋ ClO reaction under tropospheric conditions.

关键词： Radical-molecule complex H-abstraction reaction reaction rate constants Quantum chemical calculations

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：