物理化学期刊(英文)最新文献_第9页

Products and Kinetics of the Reaction of Monomeric Target Bis-(Acetylacetonato) Copper(II) with Transmetalator Bis-(Diethoxydithiophosphato) Zinc(II) in Methylene Chloride 单体靶物双(乙酰丙酮)铜(II)与转金属物双(二氧基二硫代磷酸)锌(II)在二氯甲烷中的反应产物及动力学

物理化学期刊(英文) Pub Date : 2015-05-08 DOI: 10.4236/OJPC.2015.52005

H. Abo-Eldahab

引用次数: 0

Interconversion between Planar-Triangle, Trigonal-Pyramid and Tetrahedral Configurations of Boron (B(OH)3 -B(OH)4- ), Carbon (CH3+ -CH3X) and for the Group 15 Elements as Nitrogen (NH3-NH4+ ). A Modelling Description with Ab Initio Results and Pressure-Induced Experimental Evidence 硼(B(OH)3 -B(OH)4-)、碳(CH3+ - ch3x)和15族元素氮(NH3-NH4+)的平面三角形、三角金字塔和四面体构型之间的相互转化。具有从头算结果和压力诱导实验证据的模型描述

物理化学期刊(英文) Pub Date : 2015-01-20 DOI: 10.4236/OJPC.2015.51001

H. Buck

{"title":"Interconversion between Planar-Triangle, Trigonal-Pyramid and Tetrahedral Configurations of Boron (B(OH)3 -B(OH)4- ), Carbon (CH3+ -CH3X) and for the Group 15 Elements as Nitrogen (NH3-NH4+ ). A Modelling Description with Ab Initio Results and Pressure-Induced Experimental Evidence","authors":"H. Buck","doi":"10.4236/OJPC.2015.51001","DOIUrl":"https://doi.org/10.4236/OJPC.2015.51001","url":null,"abstract":"Recently a mechanistic understanding of the pressure-and/or temperature-induced coordination change of boron in a borosilicate glass has been demonstrated by Edwards et al. In situ high-pressure 11B solid-state NMR spectroscopy has been used in combination with ab initio calculations in order to obtain insight in the molecular geometry for the pressure-induced conversion. The results indicate a deformation of the B(OH)3 planar triangle, under isotropic stress, into a trigonal pyramid that serves as a precursor for the formation of a tetrahedral boron configuration. From our point of view, the deformation controlling the out-of-plane transition of boron accompanied with a D3h into C3v geometric change is an interesting transformation because it matches with our molecular description based on Van’t Hoff modelling for the tetrahedral change of carbon in CH3X by substitution of X with nucleophiles via a trigonal bipyramid state in which the transferred carbon is present as a methyl planar triangle “cation”. Van’t Hoff modelling and ab initio calculations have been also applied on the dynamics of the out-of-plane geometry of a transient positively charged carbon in a trigonal pyramidal configuration into a planar trivalent carbon cation. Finally the same model is also used for the C3v trigonal pyramidal configurations as NH3 of the group 15 elements in their nucleophilic abilities.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":"05 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70501665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Thermochemical Parameters of Tetramethylthiourea Adducts of Certain Metal(II) Bromides 某些金属(II)溴化物四甲基硫脲加合物的热化学参数

物理化学期刊(英文) Pub Date : 2015-01-20 DOI: 10.4236/OJPC.2015.51002

P. Dunstan

引用次数: 0

The Relation between the Heat of Melting Point, Boiling Point, and the Activation Energy of Self-Diffusion in Accordance with the Concept of Randomized Particles 基于随机粒子概念的熔点热、沸点热与自扩散活化能的关系

物理化学期刊(英文) Pub Date : 2014-10-15 DOI: 10.4236/OJPC.2014.44019

V. P. Malyshev, A. Makasheva

引用次数: 4

Effect of Chloride Concentration on the Corrosion Rate of Maraging Steel 氯化物浓度对马氏体时效钢腐蚀速率的影响

物理化学期刊(英文) Pub Date : 2014-10-15 DOI: 10.4236/OJPC.2014.44018

H. E. Desouky, H. Abo-Eldahab

引用次数: 10

Comparative Isotherms Studies on Adsorptive Removal of Congo Red from Wastewater by Watermelon Rinds and Neem-Tree Leaves 西瓜皮和尼姆树叶吸附去除废水中刚果红的比较等温线研究

物理化学期刊(英文) Pub Date : 2014-10-15 DOI: 10.4236/OJPC.2014.44017

M. Ibrahim, Sadiq Sani

{"title":"Comparative Isotherms Studies on Adsorptive Removal of Congo Red from Wastewater by Watermelon Rinds and Neem-Tree Leaves","authors":"M. Ibrahim, Sadiq Sani","doi":"10.4236/OJPC.2014.44017","DOIUrl":"https://doi.org/10.4236/OJPC.2014.44017","url":null,"abstract":"Equilibrium adsorption studies for detoxification of Congo Red (CR) dye from single component model wastewater by powdered watermelon rinds and neem leaves adsorbents were carried out with the view to test the applicability of the adsorption process to Langmuir, Freundlich, Temkin, Dubinin-Radushkevich and Harkins-Jura isotherm models. The values of correlation coefficient, R2 (0.9359 - 0.9998), showed that all the experimental data fitted the linear plots of the tested isotherm models. Dubinin-Radushkevich’s monolayer maximum adsorption capacity qD (20.72 - 26.06 mg/g) is better than Langmuir’s qm (18.62 - 24.75 mg/g) for both adsorbents with the capacities higher for adsorption on watermelon rind than on neem leaves. Values of Langmuir separation factor (RL) suggest unfavourable adsorption processes (i.e. chemisorption) of the dye on both the adsorbents, while Freundlich constant (nF) indicates unfavourable process only for CR adsorption onto neem leaves. The Dubinin-Radushkevich’s mean free energy of adsorption, E (0.29 - 0.32 kJ/mol), suggests physical adsorption processes. Values for Temkin’s heat of adsorption, bT (-0.95 to 0.74 kJ/mol), also show physical adsorption process.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":"04 1","pages":"139-146"},"PeriodicalIF":0.0,"publicationDate":"2014-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70501648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 72

The Even-Odd Rule on Single Covalent-Bonded Structural Formulas as a Modification of Classical Structural Formulas of Multiple-Bonded Ions and Molecules 单共价键结构式的奇偶规则作为多键离子和分子经典结构式的修正

物理化学期刊(英文) Pub Date : 2014-10-15 DOI: 10.4236/OJPC.2014.44020

G. Auvert

{"title":"The Even-Odd Rule on Single Covalent-Bonded Structural Formulas as a Modification of Classical Structural Formulas of Multiple-Bonded Ions and Molecules","authors":"G. Auvert","doi":"10.4236/OJPC.2014.44020","DOIUrl":"https://doi.org/10.4236/OJPC.2014.44020","url":null,"abstract":"In organic chemistry, as defined by Abegg, Kossel, Lewis and Langmuir, compounds are normally represented using structural formulas called Lewis structures. In these structures, the octet rule is used to define the number of covalent bonds that each atom forms with its neighbors and multiple bonds are frequent. Lewis’ octet rule has unfortunately shown limitations very early when applied to non-organic compounds: most of them remain incompatible with the “rule of eight” and location of charges is uncertain. In an attempt to unify structural formulas of octet and non-octet molecules or single-charge ions, an even-odd rule was recently proposed, together with a procedure to locate charge precisely. This even-odd rule has introduced a charge-dependent effective-valence number calculated for each atom. With this number and the number of covalent bonds of each element, two even numbers are calculated. These numbers are both used to understand and draw structuralformulas of single-covalent-bonded compounds. In the present paper, a procedure is proposed to adjust structural formulas of compounds that are commonly represented with multiple bonds. In order to keep them compatible with the even-odd rule, they will be represented using only single covalent bonds. The procedure will then describe the consequences of bond simplification on charges locations. The newly obtained representations are compared to their conventional structural formulas, i.e. single-bond representation vs. multiple-bond structures. Throughout the comparison process, charges are precisely located and assigned to specific atoms. After discussion of particular cases of compounds, the paper finally concludes that a rule limiting representations of multiplecovalent bonds to single covalent bonds, seems to be suitable for numerous known compounds.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":"04 1","pages":"173-184"},"PeriodicalIF":0.0,"publicationDate":"2014-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70502025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Coherence of the Even-Odd Rule with an Effective-Valence Isoelectronicity Rule for Chemical Structural Formulas: Application to Known and Unknown Single-Covalent-Bonded Compounds 化学结构式偶奇规则与有效价等电子规则的相干性:在已知和未知单共价键化合物中的应用

物理化学期刊(英文) Pub Date : 2014-07-29 DOI: 10.4236/OJPC.2014.43015

G. Auvert

{"title":"Coherence of the Even-Odd Rule with an Effective-Valence Isoelectronicity Rule for Chemical Structural Formulas: Application to Known and Unknown Single-Covalent-Bonded Compounds","authors":"G. Auvert","doi":"10.4236/OJPC.2014.43015","DOIUrl":"https://doi.org/10.4236/OJPC.2014.43015","url":null,"abstract":"Ions or molecules are said \u0000to be isoelectronic if they are composed of different elements but have the \u0000same number of electrons, the same number of covalent bonds and the same \u0000structure. This criterion is unfortunately not sufficient to ensure that a \u0000chemical structure is a valid chemical compound. In a previous article, a \u0000procedure has been described to draw 2D valid structural formulas: the even-odd \u0000rule. This rule has been applied first to single-bonded molecules then to \u0000single-charged single-bonded ions. It covers hypovalent, hypervalent or classic \u0000Lewis’ octet compounds. The funding principle of the even-odd rule is that each \u0000atom of the compound possesses an outer-shell filled only with pairs of \u0000electrons. The application of this rule guarantees validity of any \u0000single-covalent-bond chemical structure. In the present paper, this even-odd \u0000rule and its electron-pair criterion are checked for coherence with an \u0000effective-valence isoelectronic rule using numerous known compounds having \u0000single-covalent-bond connections. The test addresses Lewis’ octet ions or \u0000molecules as well as hypovalent and hypervalent compounds. The article \u0000concludes that the even-odd rule and the effective-valence isoelectronicity \u0000rule are coherent for known single-covalent-bond chemical compounds.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":"4 1","pages":"126-133"},"PeriodicalIF":0.0,"publicationDate":"2014-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70501248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Characterization and Adsorption Study of Thymol on Pillared Bentonite 百里香酚在膨润土上的表征及吸附研究

物理化学期刊(英文) Pub Date : 2014-07-29 DOI: 10.4236/OJPC.2014.43013

M. E. miz, S. Salhi, Ikrame Chraibi, A. Bachiri, M. Fauconnier, A. Tahani

{"title":"Characterization and Adsorption Study of Thymol on Pillared Bentonite","authors":"M. E. miz, S. Salhi, Ikrame Chraibi, A. Bachiri, M. Fauconnier, A. Tahani","doi":"10.4236/OJPC.2014.43013","DOIUrl":"https://doi.org/10.4236/OJPC.2014.43013","url":null,"abstract":"Pillared clay (PILC) was prepared from Moroccan clay and \u0000characterized, and its aqueous thymol adsorption capacities were studied using \u0000a batch equilibrium technique. So, we tested the encapsulation of thymol by \u0000aluminum pillared clay (PILC). The PILCs displayed a total surface area of 270 \u0000m2/g, a total pore volume of 0.246 cm3/g and an average \u0000pore diameter of 8.9 A, which corresponds to the size of Al13 forming the pillars between the clay \u0000layers. The adsorption capacity shown by the PILCs for thymol from water is \u0000close to 319 mg?g-1 for \u0000low solid/liquid ratio (0.2%). This result suggests that the PILCs have both \u0000hydrophobic and hydrophilic characteristics, as a result of the presence of \u0000silanol and siloxane groups formed during the pillaring and calcination of the \u0000PILCs. The experimental data were analyzed by the Freundlich and the Langmuir \u0000isotherm types for low values of equilibrium concentration. The rise of the \u0000isotherm in this range of concentrations was related to the affinity of thymol \u0000for clay sites, and the equilibrium data fitted well with the Freundlich model \u0000with maximum adsorption capacity of 319.51 mg/g for a ratio RS/L = 0.2%. Pseudo-first and \u0000pseudo-second-order kinetic models were tested with the experimental data and \u0000pseudo-first order kinetics was the best for the adsorption of thymol with \u0000coefficients of correlation R2 ≥0.986, and the adsorption was rapid with 90% of \u0000the thymol adsorbed within the first 20 min.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":"4 1","pages":"98-116"},"PeriodicalIF":0.0,"publicationDate":"2014-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4236/OJPC.2014.43013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70501543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 26

Comparative Study of Physical Properties of In-Use Surfactant-Grafted Polyacrylamides for Oilfield 油田用表面活性剂接枝聚丙烯酰胺物性比较研究

物理化学期刊(英文) Pub Date : 2014-07-29 DOI: 10.4236/OJPC.2014.43016

Tingting Jiang, Haiyu Wang, Baohui Wang

引用次数: 1