Current physical chemistry最新文献

{"title":"Acknowledgements to Reviewers","authors":"","doi":"10.2174/187794681303230818104529","DOIUrl":"https://doi.org/10.2174/187794681303230818104529","url":null,"abstract":"","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":"86 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136172311","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":"Effect of Laterally Substituted Methoxy Group on the Liquid Crystalline Behavior of Novel Ester Molecules","authors":"Neha Baku, Jwalant Travadi, Kartik Ladva","doi":"10.2174/1877946813666230809121625","DOIUrl":"https://doi.org/10.2174/1877946813666230809121625","url":null,"abstract":"Background: The aim of this research is to study the effect of length-to-width ratio on mesomorphism to enhance the understanding of its potential applications. This will be achieved by synthesizing a unique and innovative series of identical ester molecules, including lateral methoxy groups and terminal ethyl benzoate groups. In this research, we aim to find new insights into the relationship between molecular structures and mesomorphic behaviors, which could have significant implications for the development of advanced materials with adapted properties. Objective: The objective of the study is to investigate the mesophase behavior of new ester mesogens and determine how they are influenced by lateral methoxy groups. By identifying the underlying perspectives and relationships between these variables, we hope to better understand the unique properties and potential applications of these materials. Method: In this research work, the focus is on the synthesis of ethyl(E)-4-((3-(4-alkoxy-3-methoxyphenyl)acryloyl)oxy)benzoate, which is prepared from Steglich esterification method by using (E)-3-(4-alkoxy-3-methoxyphenyl)acrylic acid and ethyl 4-hydroxybenzoate. Synthesis processes involve precise reaction sequences designed to ensure maximum yield and purity of the final product. By providing a detailed report on the experimental process, this study contributes to the ongoing research efforts aimed at the development of innovative compounds with various applications in liquid crystals. Result: A new set of liquid crystal derivatives has been synthesized and studied to investigate the effect of molecular structure on the behavior of liquid crystals, with particular attention to the group -OCH3 located laterally. This series was composed of 12 derivatives (C1-C16). Among them, the first six derivatives (C1-C6) did not have the characteristics of a liquid crystal, while the remaining derivatives (C7 and C8) had a monotropic behavior, and C10-C16 had an enantiotropic smectogenic liquid crystal behavior without exhibition of the nematic phase. The average thermal stability of the smectic property was 87.33 °C, and the mesophase range was 2 °C to 14 °C. The molecular structure was confirmed by analytical and spectral analysis. The properties of liquid crystals of this new series were compared with those of other known structurally similar homologous series. The transition temperatures were determined with an optical polarizing microscope equipped with a heating phase. Conclusion: The mesomorphic thermal and optical properties of the compounds have been validated by DSC and POM techniques. The result shows that the length of the alkyl chain has a significant influence on the mesomorphic characteristics and thermal stability of the different mesophases. Evaluation of the compounds studied indicates that the molecules are sensitive to their lateral substituent, which influences the thermal characteristics and stability of the mesophase.","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135647526","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":"Drug Polymorphism: An Important Pre-formulation Tool in the Formulation Development of a Dosage Form","authors":"Shaweta Sharma, Prateek Singh, P. Sharma, Aftab Alam","doi":"10.2174/1877946813666230822113606","DOIUrl":"https://doi.org/10.2174/1877946813666230822113606","url":null,"abstract":"\u0000\u0000Polymorphism permits solids to have two or multiple crystal structures with varying orientations or conformations, and polymorph drug dissolution and solubility vary. Polymorphism influences drug efficacy, bioavailability and toxicity. Various parameters can regulate polymorph crystallization, including supersaturation phase, temperature, stirring rate, solvent addition rate, seed crystal, additives and pH. To characterize and monitor polymorphs, various analytical approaches are available, including powder X-Ray diffraction / X-Ray diffraction (PXRD/XRD), also called as Gold Standard method, differential scanning calorimetry (DSC), Infrared spectroscopy (IR), and microscopical studies. To prevent polymorphic change during production, distribution, and storage, formulation with the most stable form in the marketed product is considered. In addition, by monitoring each phase of raw material processing, polymorphisms can be controlled during dosage form manufacturing. \u0000The objective of this review is to provide concise information on drug polymorphism, their characterization process, their effect on the stability of dosage forms, factors controlling polymorphism in the crystallization process, some case studies on polymorphs, control of polymorphism during the formulation of successful dosage forms and some of the regulatory considerations regarding polymorphs.\u0000Various databases like Pubmed/Medline, Google Scholar and Web of Science of all English language articles were searched, and relevant information was collected regarding the importance of polymorphism in formulation development.\u0000From a vast literature survey, it was found that polymorphism is a very important tool in a pre-formulation study that provides information about the fate of a drug molecule in its journey.\u0000From the present study, it was concluded that the polymorphism property of a drug should be taken into consideration at the pre-formulation stage since it is a very important tool for the formulation of a successful dosage form with stability and efficacy.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48308396","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":"Doping Induced Optical Band Gap Modification Of Potassium Dihydrogen Phosphate","authors":"Vijeesh P, Muneer E.M, Shifa K, A. V, V. R","doi":"10.2174/1877946813666230727104555","DOIUrl":"https://doi.org/10.2174/1877946813666230727104555","url":null,"abstract":"\u0000\u0000Potassium dihydrogen phosphate (KDP) is an excellent nonlinear optical material that has many potential applications, such as laser frequency conversion, Q-switches, Pockels cells, 3-D optical data storage devices, etc. Doping enhances various optical parameters of KDP. Doping changes in the absorbance and dopants such as aspartic acid, succinic acid, glycine, and L-alanine improved the optical band gap of the sample.\u0000\u0000\u0000\u0000KDP is a non-linear optic material that has many important applications. Many researchers all over the world are trying to improve its optical properties.\u0000\u0000\u0000\u0000To synthesise pure KDP and KDP doped with aspartic acid, succinic acid, glycine, and L-alanine. Also, to study the temperature stability of the grown samples using TGA, DTA, and DSC analysis,\u0000\u0000\u0000\u0000Growth from solution at low temperatures is used for the growth of crystals. TGA, DTA, and DSC are used to analyse the stability of the samples against temperature variations.\u0000\u0000\u0000\u0000KDP crystals of good quality were grown using the slow cooling solution growth technique. Determined their band gap using the Tauc Plot. Significant variations in the optical bandgap are noticed. Also, the TGA, DTA, and DSC characterizations were done.\u0000\u0000\u0000\u0000KDP solution and grown crystals of good quality were synthesized. The variation in the bandgap on\u0000doping is a significant result as the modifications in bandgap enable the sample to be used in a more enhanced\u0000applications. Also, the doped samples were stable for variations in temperature, like the pure KDP.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44174614","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":"Biopolymers and their Nanocomposites: current status and future prospects","authors":"N. Aggarwal, Dipti Dhiman, N. Kaur, H. Kaur, Sonika Arti","doi":"10.2174/1877946813666230726125759","DOIUrl":"https://doi.org/10.2174/1877946813666230726125759","url":null,"abstract":"\u0000\u0000For many years, petroleum-based polymers have been successfully enhanced by the addition of nanoparticles as additives. Carbon nanotubes, graphene, nanoclays, 2-D layered materials, and cellulose nano whiskers are a few of the several nano-reinforcements that are currently being researched. In comparison to unmodified polymer resin, the use of these nanofillers with bio-based polymers could improve a wide range of physical properties, including barrier, flame resistance, thermal stability, solvent uptake, and rate of biodegradability. This nano-reinforcement is a very appealing method to create new functional biomaterials for a variety of applications because these enhancements are typically achieved at minimal filler content. In Fig. 1, the interaction of biopolymers with nanocomposites is shown as improving the functionality of electronic, photonic and optical devices.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44030902","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":"Preparation and Characterisation and performance of Copper (II) surfactant as Cu(II) complex","authors":"Vandana Sukhadia, Rashmi Sharma, Asha Meena","doi":"10.2174/1877946813666230720111013","DOIUrl":"https://doi.org/10.2174/1877946813666230720111013","url":null,"abstract":"\u0000\u0000Organic synthesis, under environment-friendly circumstances, has a great impact on sustainable development. In this perspective, visible light photocatalysis has emerged as a green model, as this offers an energy-efficient pathway towards organic conversion. Light has been used as an energy source in this study, which is also a green approach to a sustainable environment.\u0000\u0000\u0000\u0000An investigation of the effects of various physical parameters, like the amount of complex, catalyst dose, and varying polarity of solvent methanol-benzene, on the photocatalytic degradation of surfactant as copper (II) mustard 2-amino 6-methyl benzothiazole complex has been carried out under the UV-visible light source. Biocidal activities of Staphylococcus aureus have also been studied in this work.\u0000\u0000\u0000\u0000The rate of percent degradation has been found to increase with an increase in the range of parameters.\u0000\u0000\u0000\u0000This study provides a deeper experimental knowledge of the photocatalysis processes as well as microbial activities of the copper (II) mustard 2-amino 6-methyl benzothiazole complex. This article deals with advances in photocatalytic methods under non-aqueous media over the past few years.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46824313","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":"Physicochemical Properties of Cetrimonium Bromide in Electrolytes and Nonelectrolyte Environments","authors":"T. Joshi, Riddhi H. Joshi, Nikunj N. Dave","doi":"10.2174/1877946813666230720164941","DOIUrl":"https://doi.org/10.2174/1877946813666230720164941","url":null,"abstract":"\u0000\u0000The physicochemical properties, including the thermodynamics of micellization studies, received much attention. Cationic surfactant cetrimonium bromide (C16TABr) in electrolytes (sodium chloride and sodium salicylate) and nonelectrolyte (Ethylene glycol) in an aqueous solution were examined, and interesting results were obtained. The present investigation aims to identify a suitable combination of cationic surfactant cetrimonium bromideelectrolytes and nonelectrolytes having the ability to alter the size or shape of the micellar system using available methods.\u0000\u0000\u0000\u0000Surface tension, conductivity, viscosity, ultrasonic velocity, and dynamic light scattering (DLS) methods at different temperatures (303-323K) were used during the experimental research work.\u0000\u0000\u0000\u0000The experimental results pointed out that the incorporation of electrolytes and nonelectrolyte into the cationic surfactant affects the physicochemical properties such as critical micelle concentration (CMC), surface tension (ST), degree of ionization (α), degree of counterion binding (β), standard Gibbs free energy of micellization (ΔGom), standard entropy of micellization (ΔSom), standard heat of micellization (ΔHom), viscosities, and acoustic parameters. Dynamic light scattering (DLS) measurements reveal exciting facts related to the size and shape transformation of the mixed micellar assembly. Structure modification can be obtained by choosing the combination of cationic surfactant cetrimonium bromide + electrolytes (sodium chloride and sodium salicylate) and nonelectrolyte (Ethylene glycol) ratio.\u0000\u0000\u0000\u0000From this it is concluded that an electrolyte concentration such as NaCl above a threshold value leads to an increase in micelle size. The entropy of micellization goes down when a structure-breaker (EG) is added to the water phase, and this is because the structure of the water is changed near hydrophobic groups. The physicochemical features of cetrimonium bromide (C16TABr) show unique behaviour under the influence of micelle-driven and micelle-forbidden systems.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45059049","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":"Why Thermodynamic Entropy And Statistical Entropy Are Two Different Physical Quantities","authors":"A. Paglietti","doi":"10.2174/1877946813666230622161503","DOIUrl":"https://doi.org/10.2174/1877946813666230622161503","url":null,"abstract":"\u0000\u0000Historically, the coincidence of classical thermodynamic entropy and statistical entropy is based on an assumption (the so-called Boltzmann-Planck relation).\u0000The study shows that the Boltzmann-Planck relation is not valid in general.\u0000\u0000\u0000\u0000The study demonstrates that thermodynamic entropy is a physical entity distinct from statistical entropy.\u0000\u0000\u0000\u0000Initially, the entropy of ideal gases was examined and demonstrated to be independent of the gas volume. The ideal gas's true entropy was then expressed correctly.\u0000\u0000\u0000\u0000The Boltzmann-Planck entropy equation is demonstrated to be incapable of describing the thermodynamic entropy of ideal gases.\u0000\u0000\u0000\u0000In general, the Boltzmann-Planck entropy cannot be considered a statistical interpretation of the thermodynamic entropy. The two entropies represent two different physical quantities. The physical quantity that enters the second law of thermodynamics is the thermodynamic entropy, not the statistical entropy. \u0000The study advocates for a fundamental rethinking of today's statistical understanding of thermodynamics.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41412268","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":"Interactions Among Temperature, pH, and Agitation May Cause Instability in an Oil-in-water Emulsion","authors":"Saeid Hatam, Sina Mohammadinejad, G. Hatam","doi":"10.2174/1877946813666230614124625","DOIUrl":"https://doi.org/10.2174/1877946813666230614124625","url":null,"abstract":"\u0000\u0000Two key features of an emulsion, stability and viscosity, are not only considered dependent on ingredient quantities but also delicately affected by emulsification conditions, such as pH, temperature, and mixing conditions. In the laboratory, we formulated an O/W emulsion made up of 41% water, 9.8% silicon (polydimethylsiloxane), 22.1% liquid sucrose (700 mg/ml), 22.1% light liquid paraffin, and 1.5 to 5% paraffin emulsifier by volume % purposed for large-scale production as a rubber coating for decorative purposes. This emulsion became faulty after large-scale production, while it was fine on the laboratory scale. This study investigated the probability of a complicated interaction among pH, temperature, solutes, and agitation intensity on the stability and viscosity of our emulsion by focusing on sugar degradation effects on these parameters. This emulsion was made in two different temperatures and agitation rates, and the emulsification time was 20 minutes for all samples. The critical roles of appropriate pH regulators or buffers in the stability were also investigated. It was found that applying intense agitations at 1500 rpm during emulsifications in high temperatures may lead to absurdly high emulsion viscosity, accompanied by a sharp pH fall.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45705010","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":"Micellar Effect On The Oxidation Of Anisaldehyde By Quinolinium Dichromate In Aqueous Acidic Media: A Kinetic Study","authors":"M. Yadav, M. Meena, B. Meena, Kamini Meena","doi":"10.2174/1877946813666230602092010","DOIUrl":"https://doi.org/10.2174/1877946813666230602092010","url":null,"abstract":"\u0000\u0000Oxidation of p-anisaldehyde by Quinolinium dichromate (QDC) in the aqueous acetic acid medium in the presence of sulphuric acid using surfactants.\u0000\u0000\u0000\u0000The oxidation studies of anisaldehyde is very important as the oxidized products are used as a synthetic intermediate for the preparation of a variety of drugs. Quinolinium dichromate (QDC) has emerged as a very useful and versatile oxidant. Micellar medium enhances the reaction rate.\u0000\u0000\u0000\u00001. To study the kinetics of the reaction, which includes the determination of order, rate, and activation parameters. 2. Spectral characterization of QDC by NMR and the kinetic study of the reaction mechanism is done through UV – A visible spectrophotometer. 3. Solvent effect for the oxidation of anisaldehyde by QDC. 4. Determination of critical micelle concentration (CMC) of used surfactants (CTAB and SDS).\u0000\u0000\u0000\u0000The reactions were followed at constant temperature and were followed by monitoring the UV – Visible spectrophotometer (Double Beam – 2203) in a quartz cuvette of 1 cm path length by following the absorbance decay of Cr (VI) at 440 nm\u0000\u0000\u0000\u0000KINETIC RESULTS: 1. The reaction follows first-order dependence on p-anisaldehyde and QDC. 2. The reaction is found to be acid-catalysed. A plot of log [k] versus log [H+] was found to be a straight line with a slope of 1.07. EFFECT OF SOLVENT: The rate of reaction increases with the increase in acetic acid proportion in the medium, which suggests that the reactions were of the ion–dipole type. MICELLAR EFFECT: 1. Experimental results demonstrated that anionic surfactant SDS catalysed and accelerated the study more effectively than CTAB, which is a cationic surfactant, and the rate of reaction increases with an increase in the concentration of the SDS while in the case of CTAB, the rate decreases with an increase in its concentration. 2. CMC values of CTAB and SDS were 3.9 mM and 8.2 mM, respectively.\u0000\u0000\u0000\u0000The value of negative ΔS (entropy of activation) and positive ΔH (enthalpy of activation) suggests the formation of more ordered activated complexes, and the transition state is highly solvated. SPECTROSCOPIC ANALYSIS 1.NMR characterisation of synthesised QDC shows a resemblance with pure QDC. 2. Effect of oxidant QDC, p-anisaldehyde and acid was studied by considering the spectra of the reaction mixture and varying their concentration.\u0000","PeriodicalId":89671,"journal":{"name":"Current physical chemistry","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45553827","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}