物理化学期刊(英文)最新文献

{"title":"Thermodynamic Study and Spectroscopic Analysis of a Charge-Transfer Complex between 3,5-Diamino-1,2,4-Triazole and 6-Methyl-1,3,5-Triazine-2,4-Diamine with Chloranilic Acid","authors":"K. Al-Ahmary, Ashwaq Alharbi","doi":"10.4236/ojpc.2020.101002","DOIUrl":"https://doi.org/10.4236/ojpc.2020.101002","url":null,"abstract":"Studying of charge-transfer (CT) \u0000and proton transfer interactions is essential due to their important role in \u0000many biological field and industrial applications. The current work will add \u0000more information’s about the nature of interaction between \u00003,5-diamino-1,2,4-triazole (DAT) and 6-methyl-1,3,5-triazine-2,4-diamine (MTDA) with 3,6-dichloro-2,5-dihydroxy-p-benzoquinone (chloranilic acid CLA) \u0000which was studied spectrophotometrically in Ethanol (EtOH) and Methanol (MeOH) \u0000solvents at different temperatures. The molecular composition of the formed \u0000complexes was studied by applying continuous variation and spectrophotometric \u0000titration methods and found to be 1:1 charge transfer complex for both Complex \u0000(DAT:CLA) and (MTDA:CLA) which are produced. Minimum-Maximum \u0000absorbance’s method has been applied to calculate the formation constant KCT and molecular \u0000extinction coefficient (e); they recorded \u0000high values confirming high stability of the produced complexes. Oscillator \u0000strength (f), transition dipole moment (μ), \u0000ionization potential (IP) \u0000and dissociation energy (W) of the formed CT-complexes were also \u0000determined and evaluated; they showed solvent dependency. It is concluded \u0000that the formation constant (KCT) of the complexes is found to depend on the \u0000nature of both electron acceptor and donors and on the polarity of solvents.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45211943","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}

{"title":"Taking into Account Density Fluctuations in a Solvent in a Model of Dissolution","authors":"I. A. Ar'ev","doi":"10.4236/ojpc.2019.94012","DOIUrl":"https://doi.org/10.4236/ojpc.2019.94012","url":null,"abstract":"Earlier it was shown by different authors that there are cavities (vacancies, holes) in any liquid. The cavities should play a prominent role in dissolution processes. Nevertheless this fact was ignored in previous model of dissolution. The sizes of the cavities in different solvents containing benzene molecules were determined using solvent induced spectral shift method. The measurements of S1←S0 benzene transition spectral shifts permit to conclude that 1) macroscopic excess volumes play an almost negligible role in processes of benzene dissolution in very different solvents and 2) the minimal size of the cavity in water able to accommodate benzene molecule coincides with the solute size. Generalization of this conclusion to other nonpolar aromatics leads to evaluation contraction of the solutes under aqueous solvent influence permits to predict the solubility values of other aromatics in water and to evaluate effect of enhancement hydrate cell around these molecules on solubility.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44384711","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}

{"title":"Electrochemical Study of the Synergistic Effect of Two Copper Corrosion Inhibitors, Nicotinic Acid (NAC) and Nicotinamide (NAM) in Two Different Media","authors":"Y. S. Brou, N. H. Coulibaly, N. Y. S. Diki, J. Creus, A. Trokourey","doi":"10.4236/ojpc.2019.94011","DOIUrl":"https://doi.org/10.4236/ojpc.2019.94011","url":null,"abstract":"Inhibitive properties of NAC and NAM as well as their mixture have been investigated in two different corrosive media through potentiodynamic polarization and electrochemical impedance spectroscopy at 298 K. These electrochemical measurements indicate that the inhibition efficiency increases with the concentration for each of the inhibitors used separately as well as for their mixture. In both cases, the combination behaves as mixed type inhibitor with a great cathodic tendency. NaCl 3.5% highlights an antagonist effect of NAM which reduces the effectiveness of NAC whereas HNO3 1M shows a synergistic effect between them.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47041006","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}

{"title":"Dipole Moments of the Bioactive Constituents Present in Flutab Drug by Ab-Initio Calculations","authors":"Raghad Alajlani, Amal Alssadi","doi":"10.4236/ojpc.2019.94013","DOIUrl":"https://doi.org/10.4236/ojpc.2019.94013","url":null,"abstract":"Many of the technology and computational chemistry applications are used to study drugs and their biological effects. Flutab® drug contains Paracetamol, Diphenhydramine and Pseudoephedrine. Ab-initio calculations were performed at DFT/B3LYP and HF methods with three basis sets, namely, STO-3G, 3-21G, and 6-31G(d) in order to calculate the dipole moments of the three constituents of Flutab® drug. The Diphenhydramine compound was found to be the most stable constituent, with the lowest value of dipole moment.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49337573","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}

{"title":"One-Electron-Addition to Pentavalent Phosphorus with the Phosphorus-Chlorine Bond as Acceptor Introducing a Fundamental Distinction in Substitution Mechanism between SN2(P) and SN2(C)","authors":"H. Buck","doi":"10.4236/ojpc.2019.93010","DOIUrl":"https://doi.org/10.4236/ojpc.2019.93010","url":null,"abstract":"An electron-addition, under single-crystal \u0000conditions, to pentavalent phosphorus compounds as Cl-P (=O, S) Y, Z with the P-Cl bond as electron-accepting group, is selected as an \u0000additional model for SN2(P) like reactions. It is demonstrated that the geometric information stored in the tetrahedral \u0000configuration (substrate) can be transmitted in the corresponding trigonal \u0000bipyramidal (TBP) state for nucleophilic substitution. In this article, we \u0000focus on these specific mechanistic aspects of carbon and phosphorus. We \u0000consider our study as a contribution to the significance of these (bio)chemical \u0000intermediates.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48239075","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}

{"title":"Clusters: Viscosity Cause?","authors":"V. P. Malyshev, A. Makasheva","doi":"10.4236/OJPC.2019.93007","DOIUrl":"https://doi.org/10.4236/OJPC.2019.93007","url":null,"abstract":"The significance of the work is determined by the need to develop a cluster theory of the liquid state of a substance in order to more deeply substantiate the viscosity, which is still expressed by empirical parameters within the framework of ideal ideas about the stratified flow of a liquid. According to the reference data on the dynamic viscosity of the melts for chlorides of the first group of the Periodic System, the approximating dependences in the form of cluster-associate and Frenkel’s models were constructed at various temperatures. The first model is based on taking into account the share of particles that cannot overcome the thermal melting barrier and thus serve to form virtual clusters and associates while preserving the structural motifs of the solid phase. In the framework of the cluster-associate viscosity model developed by the authors, these formations determine the melt viscosity and serve as flow units to which the energy of fluid motion is applied. The Frenkel’s model allows us to estimate the activation energy of fluidity. Calculations show that by comparing this energy with the degree of cluster association obtained in the framework of the cluster-associate model, a fairly close linear correlation is obtained, and the proportionality coefficient has the meaning of the activation energy per cluster. This energy does not go beyond the van der Waals energy of the unsaturated intermolecular bond characteristic of the interaction of particles in a liquid. This confirms the earlier established by the authors a similar pattern for melts of simple substances, based on the understanding of fluidity as a consequence of the destruction of cluster associates while preserving the clusters themselves.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49001710","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}

{"title":"Thermochemical Characterization of Casamance Biomass Residues for Production of Combustibles Briquettes","authors":"Mamadou Bâ, L. Ndiaye, I. Youm","doi":"10.4236/OJPC.2019.93009","DOIUrl":"https://doi.org/10.4236/OJPC.2019.93009","url":null,"abstract":"The \u0000development of alternatives energies illustrates the common interest of all \u0000countries in reducing greenhouse gas emissions and combating climate change. \u0000Thermochemical treatment of municipal solid waste, agricultural and forestry \u0000wastes is a major challenge for this XXIst century to replace \u0000petroleum fuels. Thermogravimetric analysis (TGA) makes it possible to \u0000elucidate the thermal behavior of Casamance (Senegal) biomass residues, mass \u0000losses and decomposition rate, under inert (N2) atmosphere and oxidizing \u0000(O2) atmosphere. Carbonization and briquetting techniques of these various residues encountered in this part of Senegal country, \u0000by densification in order to produce fuel briquettes (call biochars) will be \u0000used to improve stoves for cooking. Samples used in this study are peanuts \u0000shells (PNS), cashew nut shells (CNS), palm nut shells (PLS) and millet stems \u0000(MS). Elemental and approximate analyses make it possible to determine the CHNSO* composition, volatile matter, \u0000fixed carbon and ashes content of the samples used. Higher heating values (HHV) \u0000of the former residues are ranging from 28.60 MJ·kg-1, 26.51 MJ·kg-1, 29.69 MJ·kg-1 and 24.93 MJ·kg-1 respectively. The chars are obtained by slow pyrolysis with a heating \u0000rate of 5°C·min-1 from ambient temperature up to 800°C under inert atmosphere. The morphology of the \u0000samples is different for the four biomasses studied, from biomass in the form \u0000of wood fibers to a more compact biomass. \u0000The parietal composition of different samples presented was determined by Van \u0000Soest method using neutral detergents (NDS), acid detergent (ADS) and sulfuric \u0000acid (H2SO4, 72%); to solubilize successively extractable, \u0000hemicellulose and cellulose respectively; lignin was obtained by balance (Table 2). The samples show a high level of cellulose, this pseudo-component is \u0000very rich in carbon directly linked to the calorific value, whose values vary \u0000from 32.35%; 24.20%; 34.94% and 39.67% for PNS, PLS, CNS and MS respectively.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43887829","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}

{"title":"A Graph Theoretical Interpretation of Different Types of Energies of Elementary Particles, Atoms and Molecules","authors":"J. Gálvez","doi":"10.4236/OJPC.2019.92003","DOIUrl":"https://doi.org/10.4236/OJPC.2019.92003","url":null,"abstract":"The present work illustrates a predictive method, based on graph theory, for different types of energy of subatomic particles, atoms and molecules, to be specific, the mass defect of the first thirteen elements of the periodic table, the rotational and vibrational energies of simple molecules (such as , H2, FH and CO) as well as the electronic energy of both atoms and molecules (conjugated alkenes). It is shown that such a diverse group of energies can be expressed as a function of few simple graph-theoretical descriptors, resulting from assigning graphs to every wave function. Since these descriptors are closely related to the topology of the graph, it makes sense to wonder about the meaning of such relation between energy and topology and suggests points of view helping to formulate novel hypotheses about this relation.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49054024","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}

{"title":"Basic Steps in Chemical Dissociation of Gaseous Molecules Using an Even-Odd Rule, a Specifically Adapted Periodic Table and a Covalent Bonding Rule","authors":"G. Auvert","doi":"10.4236/OJPC.2019.92006","DOIUrl":"https://doi.org/10.4236/OJPC.2019.92006","url":null,"abstract":"When writing equations of chemical dissociation, students and scholars are taught two fundamental rules to balance the equation. On both sides of the equation, the types of elements and their quantity are conserved, as well as the global electrical charge. This paper introduces additional methods during dissociation of gaseous compounds, to precisely describe how electrical charges locally move and how bonding structures are modified. Specific rules revolving around electrons pairs displacements are developed and applied to about 150 dissociations of small gaseous molecules using atoms from the three first rows of the periodic table. Results obtained tend to demonstrate the relevance of these tools for chemists.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49173994","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}

{"title":"The Interaction(s) between Calf-Skin Hyaluronic Acid (Hyaluronan) and Dermal Type I Calf-Skin Collagen under 254 nm UV Radiation: Ability of Hyaluronan to Alter Qualitative and Quantitative Dimerization of Collagen Tyrosine Residues","authors":"J. Menter, Latoya Freeman, Ortega Edukye","doi":"10.4236/OJPC.2019.92004","DOIUrl":"https://doi.org/10.4236/OJPC.2019.92004","url":null,"abstract":"The extracellular matrix (ECM) is the non-cellular component present within all tissues and organs, providing not only essential physical scaffolding for the cellular constituents and initiating crucial biochemical and biomechanical cues, required for tissue morphogenesis, differentiation and homeostasis. Roughly divided into two groups, these are 1) the main fibrous ECM proteins: collagens, elastins, fibronectins and laminins. 2) Classification of proteoglycans (PGs) is based on their location and binding. Although many different molecular interactions are possible, they depend on the cells’ condition (i.e. “Normal”, Aged, Wounded/Fibrotic, and cancerous). There is little or no data that addresses the influence of the surrounding ECM on dityrosine formation. As a simpler model, we have replaced total PG with hyaluronan (HA) and have used purified calf-skin collagen tyrosine, which forms dityrosine (A2) under 254 nm UV in buffered solution and (near) physiological temperatures. Our results reveal a complicated temperature dependence involving factors relating to collagen HA structure, and collagen’s photochemical activation parameters.","PeriodicalId":59839,"journal":{"name":"物理化学期刊(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46381955","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}