Pub Date : 2024-07-08DOI: 10.3390/compounds4030028
Sofya Efimova, F. Lazar, J. Chopart, François Debray, A. Daltin
The electrodeposition of copper (Cu), silver (Ag), and their alloys has been a subject of interest since the 19th century. Primarily due to their exceptional features such as good mechanical hardness and electrical conductivity, high resistance to corrosion, and electromigration, Cu–Ag electrodeposits continue to be investigated and developed to improve their properties for different applications. This paper reviews the state of the art in the field of electroplated Cu–Ag alloys in an aqueous solution, with particular emphasis on the observed properties and variety of electrochemical processes used to produce high-quality materials. Moreover, this review paper focuses on the experimental conditions employed for Cu–Ag electrodeposition, intending to understand the basis and manipulate the processes to obtain coatings with superior characteristics and for attractive usage. Finally, the most trending applications of these coatings are discussed depending on different parameters of electrodeposition to provide prospects for potential research.
{"title":"Electrodeposition of Copper-Silver Alloys from Aqueous Solutions: A Prospective Process for Miscellaneous Usages","authors":"Sofya Efimova, F. Lazar, J. Chopart, François Debray, A. Daltin","doi":"10.3390/compounds4030028","DOIUrl":"https://doi.org/10.3390/compounds4030028","url":null,"abstract":"The electrodeposition of copper (Cu), silver (Ag), and their alloys has been a subject of interest since the 19th century. Primarily due to their exceptional features such as good mechanical hardness and electrical conductivity, high resistance to corrosion, and electromigration, Cu–Ag electrodeposits continue to be investigated and developed to improve their properties for different applications. This paper reviews the state of the art in the field of electroplated Cu–Ag alloys in an aqueous solution, with particular emphasis on the observed properties and variety of electrochemical processes used to produce high-quality materials. Moreover, this review paper focuses on the experimental conditions employed for Cu–Ag electrodeposition, intending to understand the basis and manipulate the processes to obtain coatings with superior characteristics and for attractive usage. Finally, the most trending applications of these coatings are discussed depending on different parameters of electrodeposition to provide prospects for potential research.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":" 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141668662","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}
Pub Date : 2024-07-02DOI: 10.3390/compounds4030027
D. Dionysopoulos
Dental erosion represents the gradual and irreversible depletion of dental hard tissues due to a chemical process, independent of bacterial influence. It has emerged as a notable clinical concern in recent years, primarily attributed to substantial lifestyle shifts resulting in the heightened intake and frequency of acid-containing foods and beverages. Apart from the extrinsic erosive agents derived from external sources, such as dietary habits or medication, intrinsic erosive agents may exist due to pathological reasons with the contents of the stomach including gastric juice, mainly composed of hydrochloric acid, being their sole source. Currently, bioactive materials are used in various forms for the prevention of dental erosion. Such materials include, among others, bioactive glasses (BAGs). BAGs are a type of glass that, when in contact with biological fluids, can elicit a specific biological response. When they come into contact with bodily fluids, they can initiate a series of processes, including the formation of a hydroxyapatite layer on the glass surface. This bioactivity is particularly advantageous in medical and dental applications, where BAGs are used for bone regeneration, tissue repair, and dental restorative or preventive techniques. The aim of this literature review was to analyze and discuss the role of BAGs in protecting the tooth structures from dental erosion. The analysis of the existing literature regarding this topic indicated that the use of BAGs in preventive treatments against tooth erosion can be useful in dental practice. Further clinical evidence is necessary to confirm the effectiveness of the particular preventive measures.
牙蚀是指牙齿硬组织因化学过程而逐渐出现的不可逆转的损耗，与细菌的影响无关。近年来，它已成为临床上一个值得关注的问题，这主要归因于生活方式的重大转变，导致含酸食物和饮料的摄入量和频率增加。除了来自饮食习惯或药物等外部来源的外源性侵蚀因子外，内源性侵蚀因子也可能因病理原因而存在，其唯一来源是胃内容物，包括主要由盐酸组成的胃液。目前，生物活性材料以各种形式用于预防牙齿腐蚀。这些材料包括生物活性玻璃（BAGs）等。生物活性玻璃是一种玻璃，当与生物液体接触时，可引起特定的生物反应。当它们与体液接触时，可以启动一系列过程，包括在玻璃表面形成羟基磷灰石层。这种生物活性在医疗和牙科应用中尤其具有优势，BAG 可用于骨再生、组织修复、牙科修复或预防技术。本文献综述旨在分析和讨论 BAG 在保护牙齿结构免受牙齿侵蚀方面的作用。对有关该主题的现有文献进行的分析表明，在牙科实践中使用 BAGs 对牙齿侵蚀进行预防性治疗是有用的。要确认特定预防措施的有效性，还需要进一步的临床证据。
{"title":"The Role of Bioactive Glasses in Dental Erosion―A Narrative Review","authors":"D. Dionysopoulos","doi":"10.3390/compounds4030027","DOIUrl":"https://doi.org/10.3390/compounds4030027","url":null,"abstract":"Dental erosion represents the gradual and irreversible depletion of dental hard tissues due to a chemical process, independent of bacterial influence. It has emerged as a notable clinical concern in recent years, primarily attributed to substantial lifestyle shifts resulting in the heightened intake and frequency of acid-containing foods and beverages. Apart from the extrinsic erosive agents derived from external sources, such as dietary habits or medication, intrinsic erosive agents may exist due to pathological reasons with the contents of the stomach including gastric juice, mainly composed of hydrochloric acid, being their sole source. Currently, bioactive materials are used in various forms for the prevention of dental erosion. Such materials include, among others, bioactive glasses (BAGs). BAGs are a type of glass that, when in contact with biological fluids, can elicit a specific biological response. When they come into contact with bodily fluids, they can initiate a series of processes, including the formation of a hydroxyapatite layer on the glass surface. This bioactivity is particularly advantageous in medical and dental applications, where BAGs are used for bone regeneration, tissue repair, and dental restorative or preventive techniques. The aim of this literature review was to analyze and discuss the role of BAGs in protecting the tooth structures from dental erosion. The analysis of the existing literature regarding this topic indicated that the use of BAGs in preventive treatments against tooth erosion can be useful in dental practice. Further clinical evidence is necessary to confirm the effectiveness of the particular preventive measures.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":"319 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141686670","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}
Pub Date : 2024-06-10DOI: 10.3390/compounds4020022
Maurizio D’Auria, R. Lorenz, R. Racioppi, V. Romano
SPME analysis of the scent of Epipactis microphylla showed the presence of limonene as the main component of the scent. Other components were 2,4,4,6,6,8,8-heptamethyl-1-nonene, pentadecane, and heptadecane. The scent of Epipactis palustris was characterized by pentadecane, 2,4,4,6,6,8,8-heptamethyl-1-nonene, and heptadecane. The scent of Neottia nidus avis showed the presence of kaur-16-ene as the main component of the scent. Other components were heinecosane, tetradecane, pentadecane, hexadecane, heptadecane, and 5,9,13-trimethyl-4,8,12-tetradecanal. The scent of Neottia ovata is due to pentadecane, hexadecane, and heptadecane. The scent of Limodorum abortivum showed the presence of 2,4,4,6,6,8,8-heptamethyl-1-nonene, pentadecane, hexadecane, heptadecane, and 2-(dodecyloxy)-ethanol.
{"title":"Determination of Volatile Organic Compounds in Some Epipactis, Neottia, and Limodorum Orchids Growing in Basilicata (Southern Italy)","authors":"Maurizio D’Auria, R. Lorenz, R. Racioppi, V. Romano","doi":"10.3390/compounds4020022","DOIUrl":"https://doi.org/10.3390/compounds4020022","url":null,"abstract":"SPME analysis of the scent of Epipactis microphylla showed the presence of limonene as the main component of the scent. Other components were 2,4,4,6,6,8,8-heptamethyl-1-nonene, pentadecane, and heptadecane. The scent of Epipactis palustris was characterized by pentadecane, 2,4,4,6,6,8,8-heptamethyl-1-nonene, and heptadecane. The scent of Neottia nidus avis showed the presence of kaur-16-ene as the main component of the scent. Other components were heinecosane, tetradecane, pentadecane, hexadecane, heptadecane, and 5,9,13-trimethyl-4,8,12-tetradecanal. The scent of Neottia ovata is due to pentadecane, hexadecane, and heptadecane. The scent of Limodorum abortivum showed the presence of 2,4,4,6,6,8,8-heptamethyl-1-nonene, pentadecane, hexadecane, heptadecane, and 2-(dodecyloxy)-ethanol.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":" 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141363583","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}
Pub Date : 2024-06-10DOI: 10.3390/compounds4020023
A. Tsoupras, Sofia Pafli, Charilaos Stylianoudakis, K. Ladomenou, C. Demopoulos, A. Philippopoulos
Inflammation and thrombosis are implicated in several chronic disorders. Recent studies have outlined the way in which several compounds can offer protection against inflammation. Within this comprehensive review the so-far reported anti-inflammatory health-promoting effects of several metal-based complexes, both in vitro and in vivo, are thoroughly presented. These metal-based compounds usually interfere with various biochemical processes associated with the inflammatory response and thrombus formation and become capable of inhibiting these biochemical pathways with proposed health benefits. Emphasis is given to the multifaceted actions of metal-based complexes that have exhibited potent anti-inflammatory and antithrombotic activities against the inflammatory mediator, platelet-activating factor (PAF), and its thrombo-inflammatory signaling, as well as on their anti-platelet and antitumor health promoting properties. Furthermore, the enhancement of the anti-inflammatory potency of well-established bioactive compounds by their incorporation as ligands in several metal-based complexes is discussed. Metal-based complexes bearing natural anti-inflammatory bioactives are also outlined. Characteristic examples of both free and metal-based porphyrins are explored. These compounds are recognized to have anti-inflammatory and antithrombotic assets, in addition to other pleiotropic advantages including antibacterial or anticancer actions. Additionally, applications of metal complexes in various models of inflammatory and thrombotic complications are demonstrated. The combined results of this study show that further research is required towards the preparation of several metal-based complexes with improved pharmacological profiles. Finally, restrictions on the application of these metal-based compounds are also covered, along with their prospects for the future and the need for additional study in order to improve their efficacy and safety.
{"title":"Anti-Inflammatory and Antithrombotic Potential of Metal-Based Complexes and Porphyrins","authors":"A. Tsoupras, Sofia Pafli, Charilaos Stylianoudakis, K. Ladomenou, C. Demopoulos, A. Philippopoulos","doi":"10.3390/compounds4020023","DOIUrl":"https://doi.org/10.3390/compounds4020023","url":null,"abstract":"Inflammation and thrombosis are implicated in several chronic disorders. Recent studies have outlined the way in which several compounds can offer protection against inflammation. Within this comprehensive review the so-far reported anti-inflammatory health-promoting effects of several metal-based complexes, both in vitro and in vivo, are thoroughly presented. These metal-based compounds usually interfere with various biochemical processes associated with the inflammatory response and thrombus formation and become capable of inhibiting these biochemical pathways with proposed health benefits. Emphasis is given to the multifaceted actions of metal-based complexes that have exhibited potent anti-inflammatory and antithrombotic activities against the inflammatory mediator, platelet-activating factor (PAF), and its thrombo-inflammatory signaling, as well as on their anti-platelet and antitumor health promoting properties. Furthermore, the enhancement of the anti-inflammatory potency of well-established bioactive compounds by their incorporation as ligands in several metal-based complexes is discussed. Metal-based complexes bearing natural anti-inflammatory bioactives are also outlined. Characteristic examples of both free and metal-based porphyrins are explored. These compounds are recognized to have anti-inflammatory and antithrombotic assets, in addition to other pleiotropic advantages including antibacterial or anticancer actions. Additionally, applications of metal complexes in various models of inflammatory and thrombotic complications are demonstrated. The combined results of this study show that further research is required towards the preparation of several metal-based complexes with improved pharmacological profiles. Finally, restrictions on the application of these metal-based compounds are also covered, along with their prospects for the future and the need for additional study in order to improve their efficacy and safety.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":"103 29","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141361394","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}
Pub Date : 2024-06-06DOI: 10.3390/compounds4020021
J. Mejuto
Compounds was born in 2021 as an interdisciplinary journal with a clear vocation towards the scientific community and a tool to present its scientific achievements in an open access format that would allow a rapid and efficient dissemination of its scientific results in the field of chemistry [...]
{"title":"Feature Papers in Compounds (2022–2023)","authors":"J. Mejuto","doi":"10.3390/compounds4020021","DOIUrl":"https://doi.org/10.3390/compounds4020021","url":null,"abstract":"Compounds was born in 2021 as an interdisciplinary journal with a clear vocation towards the scientific community and a tool to present its scientific achievements in an open access format that would allow a rapid and efficient dissemination of its scientific results in the field of chemistry [...]","PeriodicalId":10621,"journal":{"name":"Compounds","volume":"26 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141379952","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}
Pub Date : 2024-05-13DOI: 10.3390/compounds4020019
Anton Soria-Lopez, Raquel Rodriguez-Fernández, Juan C. Mejuto
The basic hydrolysis of Malachite Green (MG) in the presence of β-Cyclodextrin (β-CD) has been studied using UV-Vis spectroscopic techniques and at 20 °C. β-CD was found to catalyze the basic hydrolysis. Indeed, this basic hydrolysis is catalyzed by the interaction cyclodextrin hydroxyl group, in its deprotonated form with the carbocation in the host-guest complex. The proposed model has been successfully applied to a reaction catalyzed by CD. It considers two simultaneous pathways in the aqueous medium involving free hydroxyl ions and the substrate-CD complex. The model allows us to obtain the kinetic parameters including the bimolecular rate constant between MG and HO− in bulk water (kw = 1.47 ± 0.01 mol−1s−1), the rate constant between MG and the deprotonated hydroxyl group of β-CD inside the host-guest complex (kCD = 0.25 ± 0.03 s−1) and the binding constant of MG inside the β-CD (KS = 2500 ± 50). This behavior is like the hydrolysis of Cristal Violet (CV) in the same reaction media.
{"title":"Alkaline Fading of Malachite Green in β-Cyclodextrins","authors":"Anton Soria-Lopez, Raquel Rodriguez-Fernández, Juan C. Mejuto","doi":"10.3390/compounds4020019","DOIUrl":"https://doi.org/10.3390/compounds4020019","url":null,"abstract":"The basic hydrolysis of Malachite Green (MG) in the presence of β-Cyclodextrin (β-CD) has been studied using UV-Vis spectroscopic techniques and at 20 °C. β-CD was found to catalyze the basic hydrolysis. Indeed, this basic hydrolysis is catalyzed by the interaction cyclodextrin hydroxyl group, in its deprotonated form with the carbocation in the host-guest complex. The proposed model has been successfully applied to a reaction catalyzed by CD. It considers two simultaneous pathways in the aqueous medium involving free hydroxyl ions and the substrate-CD complex. The model allows us to obtain the kinetic parameters including the bimolecular rate constant between MG and HO− in bulk water (kw = 1.47 ± 0.01 mol−1s−1), the rate constant between MG and the deprotonated hydroxyl group of β-CD inside the host-guest complex (kCD = 0.25 ± 0.03 s−1) and the binding constant of MG inside the β-CD (KS = 2500 ± 50). This behavior is like the hydrolysis of Cristal Violet (CV) in the same reaction media.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":"59 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140983461","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}
Pub Date : 2024-05-08DOI: 10.3390/compounds4020018
V. D. Makhaev, Larisa A. Petrova, Gennadii V. Shilov, Sergey M. Aldoshin
The reaction of ZrCl4 or HfCl4 with excess 2-methylpropanoic acid when boiling under reflux has been studied. The formation of polynuclear Zr and Hf complexes of the composition M2O(i-C3H7CO2)6 during prolonged reflux of the reaction mixtures was found. The complexes are very sensitive to hydrolysis, forming hexanuclear [M6(O)4(OH)4(i-C3H7CO2)12]. The reactions have a general character for aliphatic acids and can be used as an alternative to the known methods for the synthesis of polynuclear carboxylate clusters of Group 4 metals. The crystal and molecular structures of previously undescribed {[Hf6(μ3-O)4(μ3-OH)4(i-C3H7CO2)12(H2O)]·3i-C3H7COOH} have been determined. The molecular structure is a completely asymmetric hexanuclear cluster containing six Hf(IV) atoms united by a 4:4 μ3-O/OH system of bridges, and stabilized by twelve 2-methylpropanoate ligands, eight of which are bidentate bridging, three are chelating, and one is monodentate. The crystal structure of the complex includes three independent solvating 2-methylpropanoic acid molecules. The obtained IR spectroscopy data make it possible to determine the type of complexes in the reaction mixture. The results of the study may be useful for improving the catalytic systems for ethylene oligomerization.
{"title":"New Data on the Reactions of Zirconium and Hafnium Tetrachlorides with Aliphatic Acids","authors":"V. D. Makhaev, Larisa A. Petrova, Gennadii V. Shilov, Sergey M. Aldoshin","doi":"10.3390/compounds4020018","DOIUrl":"https://doi.org/10.3390/compounds4020018","url":null,"abstract":"The reaction of ZrCl4 or HfCl4 with excess 2-methylpropanoic acid when boiling under reflux has been studied. The formation of polynuclear Zr and Hf complexes of the composition M2O(i-C3H7CO2)6 during prolonged reflux of the reaction mixtures was found. The complexes are very sensitive to hydrolysis, forming hexanuclear [M6(O)4(OH)4(i-C3H7CO2)12]. The reactions have a general character for aliphatic acids and can be used as an alternative to the known methods for the synthesis of polynuclear carboxylate clusters of Group 4 metals. The crystal and molecular structures of previously undescribed {[Hf6(μ3-O)4(μ3-OH)4(i-C3H7CO2)12(H2O)]·3i-C3H7COOH} have been determined. The molecular structure is a completely asymmetric hexanuclear cluster containing six Hf(IV) atoms united by a 4:4 μ3-O/OH system of bridges, and stabilized by twelve 2-methylpropanoate ligands, eight of which are bidentate bridging, three are chelating, and one is monodentate. The crystal structure of the complex includes three independent solvating 2-methylpropanoic acid molecules. The obtained IR spectroscopy data make it possible to determine the type of complexes in the reaction mixture. The results of the study may be useful for improving the catalytic systems for ethylene oligomerization.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":" 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140998817","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}
Pub Date : 2024-04-18DOI: 10.3390/compounds4020016
Katiana Belsi, Xenia Vogiatzi, D. Palaiogiannis, Theodoros G. Chatzimitakos, S. Lalas, D. Makris
The citrus processing industry is responsible for the generation of large volumes of waste side streams, represented principally by fruit peels. These tissues are exceptionally rich in polyphenolic bioactive phytochemicals, and there has been a great industrial interest for their valorization. The examination presented herein targeted at developing a fast and straight-forward aqueous extraction process, based on ultrasonication, for the efficacious recovery of polyphenolic compounds from waste orange peels. After an initial single-factor examination, the response surface optimization showed that a maximum total polyphenol yield of 12.81 mg chlorogenic acid equivalents (GAE) per g−1 dry mass could be achieved by setting sonicator amplitude at 80%, for 15 min, using a duty cycle of 2/2 (2 s on/2 s off). Comparison of this methodology with a stirred-tank extraction demonstrated that the ultrasonication technique was equally effective, requiring ambient temperature and considerably shorter resident time. The combination of both techniques using the ultrasonication process as a pretreatment step did not boost extraction yield, and the extracts produced had similar polyphenolic composition and antioxidant activity. However, a slight enhancement of the recovery of individual constituents was noted. It is proposed that efficient extraction of polyphenolic substances from waste orange peels may be accomplished using the present methodology, which is a low-cost (ambient temperature, short time) and sustainable (water as solvent) process.
{"title":"Ultrasonication-Assisted Aqueous Extraction of Waste Orange Peel Polyphenols: Optimization of Process Variables and Effect on Extract Composition","authors":"Katiana Belsi, Xenia Vogiatzi, D. Palaiogiannis, Theodoros G. Chatzimitakos, S. Lalas, D. Makris","doi":"10.3390/compounds4020016","DOIUrl":"https://doi.org/10.3390/compounds4020016","url":null,"abstract":"The citrus processing industry is responsible for the generation of large volumes of waste side streams, represented principally by fruit peels. These tissues are exceptionally rich in polyphenolic bioactive phytochemicals, and there has been a great industrial interest for their valorization. The examination presented herein targeted at developing a fast and straight-forward aqueous extraction process, based on ultrasonication, for the efficacious recovery of polyphenolic compounds from waste orange peels. After an initial single-factor examination, the response surface optimization showed that a maximum total polyphenol yield of 12.81 mg chlorogenic acid equivalents (GAE) per g−1 dry mass could be achieved by setting sonicator amplitude at 80%, for 15 min, using a duty cycle of 2/2 (2 s on/2 s off). Comparison of this methodology with a stirred-tank extraction demonstrated that the ultrasonication technique was equally effective, requiring ambient temperature and considerably shorter resident time. The combination of both techniques using the ultrasonication process as a pretreatment step did not boost extraction yield, and the extracts produced had similar polyphenolic composition and antioxidant activity. However, a slight enhancement of the recovery of individual constituents was noted. It is proposed that efficient extraction of polyphenolic substances from waste orange peels may be accomplished using the present methodology, which is a low-cost (ambient temperature, short time) and sustainable (water as solvent) process.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":" 45","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140687186","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}
Pub Date : 2024-04-17DOI: 10.3390/compounds4020015
S. Yamada, Keigo Yoshida, Yuto Eguchi, Mitsuo Hara, M. Yasui, Tsutomu Konno
Considerable attention has been paid to (1E)-1,2-diaryldiazenes (azo dyes) possessing liquid–crystalline (LC) and optical properties because they can switch color through thermal phase transitions and photoisomerizations. Although multifunctional molecules with both LC and fluorescent properties based on a donor–π-acceptor (D-π-A)-type tolane skeleton have been developed, functional molecules possessing LC and dye properties have not yet been developed. Therefore, this study proposes to develop LC dyes consisting of (1E)-1,2-diaryldiazenes with a D–π-A-type tolane skeleton as the aryl moiety. The (1E)-1,2-diaryldiazene derivatives exhibited a smectic phase, regardless of the flexible-chain structure, whereas the melting temperature was significantly increased by introducing fluoroalkyl moieties into the flexible chain. Evaluation of the optical properties revealed that compounds with decyloxy chains exhibited an orange color, whereas compounds with semifluoroalkoxy chains absorbed at a slightly blue-shifted wavelength, which resulted in a pale orange color. The thermal phase transition caused a slight color change accompanied by a change in the absorption properties, photoisomerization-induced shrinkage, and partial disappearance of the LC domain. These results indicate that (1E)-1,2-diaryldiazenes with a D–π-A-type tolane skeleton can function as thermo- or photoresponsive dyes and are applicable to smart windows and in photolithography.
{"title":"(1E)-1,2-Diaryldiazene Derivatives Containing a Donor–π-Acceptor-Type Tolane Skeleton as Smectic Liquid–Crystalline Dyes","authors":"S. Yamada, Keigo Yoshida, Yuto Eguchi, Mitsuo Hara, M. Yasui, Tsutomu Konno","doi":"10.3390/compounds4020015","DOIUrl":"https://doi.org/10.3390/compounds4020015","url":null,"abstract":"Considerable attention has been paid to (1E)-1,2-diaryldiazenes (azo dyes) possessing liquid–crystalline (LC) and optical properties because they can switch color through thermal phase transitions and photoisomerizations. Although multifunctional molecules with both LC and fluorescent properties based on a donor–π-acceptor (D-π-A)-type tolane skeleton have been developed, functional molecules possessing LC and dye properties have not yet been developed. Therefore, this study proposes to develop LC dyes consisting of (1E)-1,2-diaryldiazenes with a D–π-A-type tolane skeleton as the aryl moiety. The (1E)-1,2-diaryldiazene derivatives exhibited a smectic phase, regardless of the flexible-chain structure, whereas the melting temperature was significantly increased by introducing fluoroalkyl moieties into the flexible chain. Evaluation of the optical properties revealed that compounds with decyloxy chains exhibited an orange color, whereas compounds with semifluoroalkoxy chains absorbed at a slightly blue-shifted wavelength, which resulted in a pale orange color. The thermal phase transition caused a slight color change accompanied by a change in the absorption properties, photoisomerization-induced shrinkage, and partial disappearance of the LC domain. These results indicate that (1E)-1,2-diaryldiazenes with a D–π-A-type tolane skeleton can function as thermo- or photoresponsive dyes and are applicable to smart windows and in photolithography.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":"5 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140693154","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}
Here, we successfully synthesized Sr-doped perovskite-type oxides of La1−xSrxCo1−λO3−δ, “LSX” (x = 0, 0.1, 0.3, 0.5, 0.7), using the glycine-assisted solution combustion method. The effect of strontium doping on the catalyst structure, NO to NO2 conversion, NOx adsorption and storage, and NOx reduction performance were investigated. The physicochemical properties of the catalysts were studied by XRD, SEM-EDS, N2 adsorption–desorption, FTIR, H2-TPR, O2-TPD, and XPS techniques. The NSR performance of LaCoO3 perovskite was improved after Sr doping. Specifically, the perovskite with 50% of Sr doping (LS5 sample) exhibited excellent NOx storage capacity within a wide temperature range (200–400 °C), and excellent stability after hydrothermal and sulfur poisoning. It also displayed the highest NOx adsorption–storage capacity (NAC: 1889 μmol/g; NSC: 1048 μmol/g) at 300 °C. This superior performance of the LS5 catalyst can be attributed to its superior reducibility, better NO oxidation capacity, increased surface Co2+ concentration, and, in particular, its generation of more oxygen vacancies. FTIR results further revealed that the LSX catalysts primarily store NOx through the “nitrate route”. During the lean–rich cycle tests, we observed an average NOx conversion rate of over 50% in the temperature range of 200–300 °C, with a maximum conversion rate of 61% achieved at 250 °C.
{"title":"NOx Storage and Reduction (NSR) Performance of Sr-Doped LaCoO3 Perovskite Prepared by Glycine-Assisted Solution Combustion","authors":"Xinru Luan, Xudong Wang, Tianfei Zhang, Liangran Gan, Jianxun Liu, Yujia Zhai, Wei Liu, Liguo Wang, Zhongpeng Wang","doi":"10.3390/compounds4020014","DOIUrl":"https://doi.org/10.3390/compounds4020014","url":null,"abstract":"Here, we successfully synthesized Sr-doped perovskite-type oxides of La1−xSrxCo1−λO3−δ, “LSX” (x = 0, 0.1, 0.3, 0.5, 0.7), using the glycine-assisted solution combustion method. The effect of strontium doping on the catalyst structure, NO to NO2 conversion, NOx adsorption and storage, and NOx reduction performance were investigated. The physicochemical properties of the catalysts were studied by XRD, SEM-EDS, N2 adsorption–desorption, FTIR, H2-TPR, O2-TPD, and XPS techniques. The NSR performance of LaCoO3 perovskite was improved after Sr doping. Specifically, the perovskite with 50% of Sr doping (LS5 sample) exhibited excellent NOx storage capacity within a wide temperature range (200–400 °C), and excellent stability after hydrothermal and sulfur poisoning. It also displayed the highest NOx adsorption–storage capacity (NAC: 1889 μmol/g; NSC: 1048 μmol/g) at 300 °C. This superior performance of the LS5 catalyst can be attributed to its superior reducibility, better NO oxidation capacity, increased surface Co2+ concentration, and, in particular, its generation of more oxygen vacancies. FTIR results further revealed that the LSX catalysts primarily store NOx through the “nitrate route”. During the lean–rich cycle tests, we observed an average NOx conversion rate of over 50% in the temperature range of 200–300 °C, with a maximum conversion rate of 61% achieved at 250 °C.","PeriodicalId":10621,"journal":{"name":"Compounds","volume":"40 22","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140728152","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}
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