Chimica Techno Acta最新文献

Investigation of the reaction of dimedone with aromatic aldehydes in the presence of copper oxide nanoparticles 氧化铜纳米颗粒存在下二甲基酮与芳香醛反应的研究

Chimica Techno Acta Pub Date : 2024-07-10 DOI: 10.15826/chimtech.2024.11.3.03

Ravina Meena, H. Sachdeva

引用次数: 0

Dispersive surface free energy of adsorbents modified by supramolecular structures of heterocyclic compounds 杂环化合物超分子结构改性吸附剂的分散表面自由能

Chimica Techno Acta Pub Date : 2024-05-13 DOI: 10.15826/chimtech.2024.11.2.10

V. Yu. Guskov, Yulia Yu. Gainullina, Alina F. Gabdulmanova, Albina N. Gareeva

{"title":"Dispersive surface free energy of adsorbents modified by supramolecular structures of heterocyclic compounds","authors":"V. Yu. Guskov, Yulia Yu. Gainullina, Alina F. Gabdulmanova, Albina N. Gareeva","doi":"10.15826/chimtech.2024.11.2.10","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.2.10","url":null,"abstract":"In the present work, the dispersive surface free energy was calculated by Dorris-Gray method for 30 samples of adsorbents modified with chiral supramolecular structures of uracil, 6-methyluracil, 5-hydroxy-6-methyluracil, 5-fluorouracil, thymine, melamine, cyanuric and barbirutic acids, and perylene-3,4,9,10-tetracarboxylic dianhydride. It was shown that the homologous series of n-alkanes is better suited for measuring dispersive surface free energy than the homologous series of alcohols. It was established that the classical Dorris-Gray method does not allow obtaining well interpretable data for the objects studied. This is due to a noticeable effect that inductive interactions of a polar surface as an inductor with nonpolar alkane molecules have on the calculated values. We suggested to modify the Dorris-Gray method, making it possible to obtain data on the dispersive component of the free energy of adsorption. It was shown that the changes in dispersive surface free energy as a result of the modification correlate well with data on the structure and properties of supramolecular ensembles of the modifiers used. The results obtained can be used to predict the enantioselectivity of chiral adsorbents.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140985977","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: 0

Cationic amphiphilic meroterpenoids: synthesis, antibacterial, antifungal and mutagenic activity 阳离子两亲经络萜类化合物：合成、抗菌、抗真菌和诱变活性

Chimica Techno Acta Pub Date : 2024-05-09 DOI: 10.15826/chimtech.2024.11.2.09

Alan Akhmedov, R. Gamirov, Yulia Panina, Alina Baklagina, Evgenia Sokolova, Pavel V Zelenikhin, Olga Babaeva, Vasily Babaev, D. Shurpik, I. Stoikov

引用次数: 0

Photoelectrochemical properties of Pt- and Ir-modified graphitic carbon nitride 铂和铱改性氮化石墨碳的光电化学特性

Chimica Techno Acta Pub Date : 2024-05-07 DOI: 10.15826/chimtech.2024.11.2.08

D. Markovskaya, Victoria A. Lomakina, E. Kozlova

{"title":"Photoelectrochemical properties of Pt- and Ir-modified graphitic carbon nitride","authors":"D. Markovskaya, Victoria A. Lomakina, E. Kozlova","doi":"10.15826/chimtech.2024.11.2.08","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.2.08","url":null,"abstract":"In this work, the photoelectrochemical properties of g-C3N4 modified with Pt, Ir and Ir/Pt bimetallic co-catalysts were studied. All prepared photoelectrodes were tested in a two-electrode cell by cyclic voltammetry, impedance spectroscopy, and the Mott-Schottky method. First, the optimal electrolyte (triethanolamine, NaCl, NaOH, Na2SO4) was selected. The highest photocurrents were recorded in 0.5 M Na2SO4. This electrolyte was used for the subsequent tests. Second, the photoelectrodes loaded with the noble metals are studied. It was shown that in case of monometallic co-catalysts, the deposition of noble metal is accompanied by the decrease of the short-circuit current density and the growth of open-circuit voltage. The simultaneous presence of bimetallic co-catalysts can significantly affect the semiconductor electron structure and photogalvanic properties. Some correlations between the short-circuit current density and the oxidation state of the noble metals were found. A linear correlation between Pt0/Pt0+Pt2+ and Jsc was observed. It was also shown that the presence of iridium in Ir3+ form favors the photocurrent generation. The highest values of the photocurrent were obtained for g-C3N4 and were equal to 0.57 mA/cm2.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141002653","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: 0

Features of electronic states in the vicinity of band gap and atomic structure of Ta- and Nb-doped Li7La3Zr2O12 掺钽和掺铌 Li7La3Zr2O12 带隙附近的电子态特征和原子结构

Chimica Techno Acta Pub Date : 2024-05-06 DOI: 10.15826/chimtech.2024.11.2.07

M.I. Vlasov, E.A. Surzhikov, A. Germov, E. Il'ina, I. A. Weinstein

引用次数: 0

CNT thin films based on epoxy mixtures: fabrication, electrical characteristics 基于环氧混合物的碳纳米管薄膜：制造、电气特性

Chimica Techno Acta Pub Date : 2024-04-10 DOI: 10.15826/chimtech.2024.11.2.05

T. Yumalin, Timur Salikhov, Biltu Mahato, Alexey Shiverskii, Sergey Abaimov, R. Salikhov

{"title":"CNT thin films based on epoxy mixtures: fabrication, electrical characteristics","authors":"T. Yumalin, Timur Salikhov, Biltu Mahato, Alexey Shiverskii, Sergey Abaimov, R. Salikhov","doi":"10.15826/chimtech.2024.11.2.05","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.2.05","url":null,"abstract":"The simple scaling of silicon transistors no longer ensures the advantages of high energy efficiency, driving research into nanotechnologies beyond silicon. Specifically, digital circuits based on carbon nanotube (CNT) field-effect transistors promise significant advantages in energy efficiency. However, the inability to perfectly control internal nanoscale defects and the variability of carbon nanotubes hinder the realization of very large-scale integrated systems. In this study, we investigated a novel method for fabricating transistors based on carbon nanotubes (CNTs) using epoxy mixtures, obtained the electrical properties of the transistors, and compared their microstructure and composition via the scanning electron microscopy. The carrier mobility on epoxy-based transistors was 28.87 cm²/V∙s, and the transistor switching frequency was 2.2 MHz. The samples exhibited electrical and physical stability over an extended period of time. The use of carbon nanotubes in epoxy resin as a conducting layer for transistors opens significant prospects in the field of electronics. The CNT-epoxy mixture technology allows for more flexible and rapid fabrication of thin-film transistors compared to classical methods. However, it is not appropriate to speak of a complete replacement; in this study, we present an alternative method for producing thin-film transistors, which may be of interest for specific purposes.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140719050","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: 0

Evaluation of electrochemical performance of antimony modified screen-printed carbon electrodes 评估锑改性丝网印刷碳电极的电化学性能

Chimica Techno Acta Pub Date : 2024-04-09 DOI: 10.15826/chimtech.2024.11.2.04

Alexander B. Kifle, N. Malakhova, A. Ivoilova, Nataliya Leonova, Svetlana Saraeva, A. Kozitsina

{"title":"Evaluation of electrochemical performance of antimony modified screen-printed carbon electrodes","authors":"Alexander B. Kifle, N. Malakhova, A. Ivoilova, Nataliya Leonova, Svetlana Saraeva, A. Kozitsina","doi":"10.15826/chimtech.2024.11.2.04","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.2.04","url":null,"abstract":"This study compares the electrochemical performance of screen-printed carbon electrodes (SPCEs) modified with antimony (Sb/SPCEs) under different potentiostatic pre-plating conditions. Neutral Red (NR) was employed as a novel redox probe to evaluate the electrochemical performance of Sb/SPCEs. It was demonstrated that NR in the protonated form performs quasi-reversible redox transformations at bare SPCE and Sb/SPCEs in phosphate buffer solutions (pH 5.5±0.5) in the potential range of (−0.30)–(−0.75) V, where the antimony is not electroactive. Sb/SPCEs were studied electrochemically by cyclic voltammetry (CV) / electrochemical impedance spectroscopy (EIS), and morphologically by scanning electron microscopy (SEM). Cyclic voltammetry investigations revealed the dependence of the electrochemical performance of Sb/SPCEs on the degree of coverage of the substrate with the metal. The obtained CV, EIS, and SEM data are consistent. The lowest charge transfer resistance (Rct) value (6 Ω) was obtained at Sb/SPCE with the highest degree of antimony coverage. To investigate the electroanalytical performance of Sb/SPCEs, nickel (II) ions were utilized as a model analyte. A study of roughness factors and sensitivity towards nickel (II) ions for Sb/SPCEs using two-tailed Pearson's criterion revealed a high degree of correlation between their electrochemical and electroanalytical properties. The results show that using NR as a redox probe can help controlling modification processes during the development of innovative antimony-containing sensors.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140723541","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: 0

Effect of carbon black from Ageratina adenophora and various other carbon anode plate additives on the performance of lead acid batteries Ageratina adenophora 炭黑和其他各种炭阳极板添加剂对铅酸电池性能的影响

Chimica Techno Acta Pub Date : 2024-04-08 DOI: 10.15826/chimtech.2024.11.2.03

Subban Ravi, Baskaran Vignesh, Nagarajan Meimoorthy, Bharathamani Dhanus Kumar, Lakshmanan Sathishkumar, Nagarajan Mohankumar, Nagarajan Kannapiran

{"title":"Effect of carbon black from Ageratina adenophora and various other carbon anode plate additives on the performance of lead acid batteries","authors":"Subban Ravi, Baskaran Vignesh, Nagarajan Meimoorthy, Bharathamani Dhanus Kumar, Lakshmanan Sathishkumar, Nagarajan Mohankumar, Nagarajan Kannapiran","doi":"10.15826/chimtech.2024.11.2.03","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.2.03","url":null,"abstract":"The incorporation of carbon materials in batteries serves to enhance its performance by improving conductivity, achieving uniform active material distribution, increasing capacity, mitigating sulfation, extending cycle life, and considering potential environmental benefits. Even though several possible mechanisms were reported, how exactly carbon works is not fully understood. In the present study a new form of carbon black was prepared from Ageratina adenophora (CBAa) and investigated for its impact on the electrical conductivity of the negative active material in 2 V lead acid cell. The performance was compared with other commercially available carbons like Graphite PG-10, Carbon N550, Carbon N330 and Carbon Vulcan. The carbon was characterised by XRD, SEM and grain size analysis. The initial capacity of the cell was consistently higher and remained stable at 4.6 W∙h; in the life cycle analysis, the cells showed 290 cycles. The post-life cycle test analysis showed that only a white layer on multiple plates indicating the onset of sulfation and there is no corrosion. The performance of the CBAa prepared in the present work was found to be better when compared with the commercially available carbons.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140729417","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: 0

A review on agrowaste based activated carbons for pollutant removal in wastewater systems 基于农业废弃物的活性炭在废水系统中去除污染物的综述

Chimica Techno Acta Pub Date : 2024-04-04 DOI: 10.15826/chimtech.2024.11.2.02

K. Okiy, Joseph Nwabanne Tagbo, Walter Peter Echeng

{"title":"A review on agrowaste based activated carbons for pollutant removal in wastewater systems","authors":"K. Okiy, Joseph Nwabanne Tagbo, Walter Peter Echeng","doi":"10.15826/chimtech.2024.11.2.02","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.2.02","url":null,"abstract":"Environmental pollution from chemicals utilized in manufacturing, pharmaceuticals, and chemical process industries is of serious concern nowadays due to the contamination that ensues when these chemicals are discharged into water bodies. Activated carbon adsorption provides an efficient and economically viable means for mitigation of toxic chemicals (i.e., heavy metals, dyes, pharmaceutics, and antibiotics). However, the exorbitant cost of commercial activated carbons has resulted in the search for low-cost alternatives for the treatment of contaminated effluents. An exhaustive literature survey in this area is necessary to know the extent of work done in this area and seek out the gaps that future research will provide answers to. In this review, various works on activated carbon utilization, batch adsorption, fixed-bed adsorption (experimental and numerical studies) are summarized. This review elucidates the different kinetic and isotherm models of agrowastes-derived activated carbon materials in context with pollutants (dyes, heavy metals, pharmaceuticals, miscellaneous adsorbates) removal through batch and column methods. In addition, fixed-bed column adsorption/regeneration methods using various activated carbons derived from agrowastes are discussed. Among these methods, heavy metal adsorption from aqueous solutions by the activated carbons is the most efficient. The deployment of mathematical and machine learning approaches (ANN and novel GMDH algorithms) in optimization of batch and continuous adsorption processes are also highlighted. Numerical simulation of fixed-column adsorption systems for more improved industrial-scale column designs is described. Conclusions and future challenges of chemicals removal from polluted wastewater utilizing agrowaste-derived activated carbons are also presented.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140743472","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: 0

Effects of coagulant bath temperature toward separation performance and antifouling properties of PVDF/CA membranes for filtration of dyes 混凝剂浴温度对用于染料过滤的 PVDF/CA 膜的分离性能和防污性能的影响

Chimica Techno Acta Pub Date : 2024-04-01 DOI: 10.15826/chimtech.2024.11.2.01

Muhammad Reza, R. Rahmayani, C. Radiman

{"title":"Effects of coagulant bath temperature toward separation performance and antifouling properties of PVDF/CA membranes for filtration of dyes","authors":"Muhammad Reza, R. Rahmayani, C. Radiman","doi":"10.15826/chimtech.2024.11.2.01","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.2.01","url":null,"abstract":"Phase inversion is used to prepare poly(vinylidene fluoride) (PVDF) microfiltration membranes by combining it with the hydrophilic polymer additive cellulose acetate (CA). For the filtration of methylene blue (MB) and acid yellow 17 (AY17), the effects of coagulant bath temperature (CBT) on the separation performance and antifouling properties are thoroughly investigated. SEM analysis shows that the membrane at higher CBT has a larger pore diameter than at lower CBT, resulting in differences in membrane surface hydrophilicity. It is found that the increase in surface hydrophilicity causes the permeability of PVDF/CA membranes to be higher at higher CBT than at lower CBT. Rejection values above 90% indicate that the membranes are more effective for MB separation at both lower and higher CBT. Otherwise, lower CBT provides better AC rejection than higher CBT. The Flux Recovery Ratio, which is higher at higher CBT, remains in the 75–95% range at lower CBT. As a result, lower CBT is better for membrane fouling resistance than higher CBT. In addition, the fouling observed at lower CBT is similar to the fouling observed at higher CBT, but lower CBT has a higher percentage of reversible fouling than higher CBT. The membranes with more reversible fouling are therefore easier to clean using the backwashing process. As a result, PVDF/CA membranes manufactured at lower CBT have better separation performance and antifouling characteristics than those manufactured at higher CBT.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140773191","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: 0