Chimica Techno Acta最新文献_第2页

Modern instrumentation and practical application of flame atomic emission spectrometry 火焰原子发射光谱法的现代仪器和实际应用

Chimica Techno Acta Pub Date : 2024-03-04 DOI: 10.15826/chimtech.2024.11.1.09

E. A. Zauer

{"title":"Modern instrumentation and practical application of flame atomic emission spectrometry","authors":"E. A. Zauer","doi":"10.15826/chimtech.2024.11.1.09","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.1.09","url":null,"abstract":"The modern instrumentation for flame atomic emission spectrometry (FAES) is overviewed: the main technical (composition of the fuel gas used, dispersing element, number of analytical channels, reference channel, detecting element, sampling method) and analytical (determined elements, range of determined concentrations, limits and the accuracy of their determination, the duration of a single measurement, the equired amount of the analyzed sample) characteristics of flame photometers for industrial and clinical use as well as spectrophotometers currently made by various manufacturers such as Sherwood Scientific Ltd., BWB Technologies UK Ltd., Labtron Equipment Ltd., Labnics Equipment Ltd. and JENWAY Ltd (UK); A.KRÜSS Optronic (Germany); Cole Parmer Instrument Company and Labfon Equipment Inc. (USA); Inesa Analytical Instrument Co., Ltd (China); OJSC Zagorsk Optical and Mechanical Plant, Unico-SIS LLC and VMK-Optoelectronics LLC (Russia); Manti Lab Solutions, Labtronics, Systonic, Globe Instruments, Electronics India, Lasany (India). The main areas of application of FAES are presented – bioenergy, agriculture (analysis of plants, soil extracts and fertilizers), mineral raw materials (geology), clinical medicine and pharmaceuticals, food industry, environmental control (analysis of drinking, technical and waste water), nuclear energy, metallurgy and chemical industry, as well as some features and problems associated with the preparation of samples for analysis by the FAES method. The review includes references to works on the practical application of FAES, published mainly from 1998 to 2023. ","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140398241","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 graphite filler on the physiochemical properties of graphite reinforced thermoset rooflite – unsaturated polyester resin composites 石墨填料对石墨增强热固性屋顶石墨-不饱和聚酯树脂复合材料理化性能的影响

Chimica Techno Acta Pub Date : 2024-02-29 DOI: 10.15826/chimtech.2024.11.1.08

M. Karunakaran, Ravi Subban, A. Thangamani, C. Thangavel

{"title":"Effect of graphite filler on the physiochemical properties of graphite reinforced thermoset rooflite – unsaturated polyester resin composites","authors":"M. Karunakaran, Ravi Subban, A. Thangamani, C. Thangavel","doi":"10.15826/chimtech.2024.11.1.08","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.1.08","url":null,"abstract":"It is well known that many polymers are insulators with poor mechanical properties, which limit their use in fuel cell applications. Physicochemical properties of the polymers can be improved by adding conductive fillers. Carbon-based materials like graphite, which provides excellent mechanical strength and thermal conductivity to the polymer matrices, is of special interest because of its abundance, low cost and light weight when compared to other carbon allotropes. In the present work we describe the physicochemical properties of rooflite unsaturated polyester resin/graphite composites. Rooflite resin and three of its composites containing 1%, 3% and 5% of graphite by weight (C-2, C-3, and C-4, respectively) were synthesized and characterized by FTIR spectral data. XRD showed two peaks at 2q = 27.37°and 55.40° with d spacing value of 3.2559 nm and 1.6571 nm, respectively, indicating the change in degree of crystallinity of the composite. The calculated crystallinity for the resin is 7.3%, and for C-2, C-3 and C-4 its values are 12.1%, 14.3%, 17.1%, respectively, evidencing the interactions between the graphite and polymer matrix. The composites showed fractured surfaces and porous rough structure with randomly distributed vascularized cavities. Agglomeration occurs, when the concentration of graphite increases. The glass transition temperature for the pure resin is 65.9 °C and increases when the resin is filled with graphite. Thermogravimetric analysis (TGA) of the composites showed no marked difference between Tmax and Tfinal, and LOI values of C-3 and C-4 are above 21%, making them self-extinguishable materials that could be used for making bipolar plates. The chemical resistance investigation against water, NaCl, NaOH, acetic acid, and toluene showed more resistance to acid than alkali solutions. These rooflite resin/graphite composites could be further studied to explore the possibility of making bipolar plates, which are an essential component of fuel cells.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140413176","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

Modification of bacterial cellulose using silk fibroin β-sheet crystals induced by ultrasonication 利用超声波诱导的丝纤维素β片晶对细菌纤维素进行改性

Chimica Techno Acta Pub Date : 2024-02-05 DOI: 10.15826/chimtech.2024.11.1.07

Mary Stephanie Carranza, Neil Andrew D. Bascos, Maria Carmen Tan, Francisco Franco Jr.

{"title":"Modification of bacterial cellulose using silk fibroin β-sheet crystals induced by ultrasonication","authors":"Mary Stephanie Carranza, Neil Andrew D. Bascos, Maria Carmen Tan, Francisco Franco Jr.","doi":"10.15826/chimtech.2024.11.1.07","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.1.07","url":null,"abstract":"Silk fibroin (SF) has been continuously explored as a biomaterial due to its biocompatibility, tunability, and self-healing properties. In this work, we present a novel approach to the modification of bacterial cellulose (BC) with SF β-sheet dominant structures induced via ultrasonication. Secondary structure analysis through infrared spectroscopy, thioflavin T assay, and circular dichroism spectropolarimetry revealed a conversion of silk I to silk II structures within the protein mixture. Cold field emission scanning electron microscope images revealed the tightly packed fibers coated with the protein. Thermogravimetric curves demonstrated higher resistance to temperature degradation supplemented by broader and flatter DSC curves attributed to the highly bonded and dense composite. Successful conversion of amide I to amide II and amide III allowed for the more stable β-crystals to contribute to a more thermodynamically stable double-network hydrogel. The conversion of silk I to silk II structures offers a viable and highly biocompatible material that is both thermodynamically and biochemically stable for various potential biomedical applications.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139862430","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

Modification of bacterial cellulose using silk fibroin β-sheet crystals induced by ultrasonication 利用超声波诱导的丝纤维素β片晶对细菌纤维素进行改性

Chimica Techno Acta Pub Date : 2024-02-05 DOI: 10.15826/chimtech.2024.11.1.07

Mary Stephanie Carranza, Neil Andrew D. Bascos, Maria Carmen Tan, Francisco Franco Jr.

{"title":"Modification of bacterial cellulose using silk fibroin β-sheet crystals induced by ultrasonication","authors":"Mary Stephanie Carranza, Neil Andrew D. Bascos, Maria Carmen Tan, Francisco Franco Jr.","doi":"10.15826/chimtech.2024.11.1.07","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.1.07","url":null,"abstract":"Silk fibroin (SF) has been continuously explored as a biomaterial due to its biocompatibility, tunability, and self-healing properties. In this work, we present a novel approach to the modification of bacterial cellulose (BC) with SF β-sheet dominant structures induced via ultrasonication. Secondary structure analysis through infrared spectroscopy, thioflavin T assay, and circular dichroism spectropolarimetry revealed a conversion of silk I to silk II structures within the protein mixture. Cold field emission scanning electron microscope images revealed the tightly packed fibers coated with the protein. Thermogravimetric curves demonstrated higher resistance to temperature degradation supplemented by broader and flatter DSC curves attributed to the highly bonded and dense composite. Successful conversion of amide I to amide II and amide III allowed for the more stable β-crystals to contribute to a more thermodynamically stable double-network hydrogel. The conversion of silk I to silk II structures offers a viable and highly biocompatible material that is both thermodynamically and biochemically stable for various potential biomedical applications.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139802786","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

Synthesis and electrical properties of doped layered perovskites based on BaMInO4 (M = Y, Gd) 基于 BaMInO4（M = Y、Gd）的掺杂层状过氧化物的合成和电学特性

Chimica Techno Acta Pub Date : 2024-02-02 DOI: 10.15826/chimtech.2024.11.1.06

Nataliia Tarasova, Maxim Mashkovtsev, Maxim Domashenkov, Denis Khionin, Roman Bastrikov, A. Bedarkova

引用次数: 0

Synthesis and electrical properties of doped layered perovskites based on BaMInO4 (M = Y, Gd) 基于 BaMInO4（M = Y、Gd）的掺杂层状过氧化物的合成和电学特性

Chimica Techno Acta Pub Date : 2024-02-02 DOI: 10.15826/chimtech.2024.11.1.06

Nataliia Tarasova, Maxim Mashkovtsev, Maxim Domashenkov, Denis Khionin, Roman Bastrikov, A. Bedarkova

引用次数: 0

Interaction of silica with polystyrene: mechanical properties, polymer/filler adhesion and failure behavior 二氧化硅与聚苯乙烯的相互作用：机械特性、聚合物/填料粘附性和失效行为

Chimica Techno Acta Pub Date : 2024-02-01 DOI: 10.15826/chimtech.2024.11.1.05

Selvin P. Thomas

引用次数: 0

Interaction of silica with polystyrene: mechanical properties, polymer/filler adhesion and failure behavior 二氧化硅与聚苯乙烯的相互作用：机械特性、聚合物/填料粘附性和失效行为

Chimica Techno Acta Pub Date : 2024-02-01 DOI: 10.15826/chimtech.2024.11.1.05

Selvin P. Thomas

引用次数: 0

Development of A. solani β-tubulin models and comparison of docking results for benzo[d]azoles derivatives as potential antifungal agents 开发 A. solani β-管蛋白模型并比较苯并[d]唑衍生物作为潜在抗真菌剂的对接结果

Chimica Techno Acta Pub Date : 2024-01-30 DOI: 10.15826/chimtech.2024.11.1.04

K. Obydennov, T. Kalinina, T. Glukhareva, V. Bakulev

{"title":"Development of A. solani β-tubulin models and comparison of docking results for benzo[d]azoles derivatives as potential antifungal agents","authors":"K. Obydennov, T. Kalinina, T. Glukhareva, V. Bakulev","doi":"10.15826/chimtech.2024.11.1.04","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.1.04","url":null,"abstract":"An approach to developing a docking protocol using free software such as KNIME, DataWarrior, AutoDock Vina, AutoDockTools, OpenBabel and the SWISS-MODEL service was described. In particular, the process of generating possible isomeric structures using KNIME chemoinformatics libraries is described. A library of benzo[d]azoles containing 145 compounds with homologous models of Alternaria solani β-tubulin obtained in two ways: using the commercial Prime program and the free SWISS-MODEL service, the comparison of results was shown. Despite the less preorganization of the binding cavity of the homologous model obtained using SWISS-MODEL, the correlation of the results between the two methods were observed. The correlation coefficients were as follows: Pearson was 0.65, Spearman was 0.62. According to the docking results, 99% of the studied 2-aminobenzo[d]azoles derivatives showed a docking score of no more than –7, which indicates that these compounds are promising for studying the fungicidal activity, in particular against A. solani. Without taking into account pharmacokinetic characteristics, benzo[d]imidazole derivatives containing a sulfanilamidine substituent at the 2-amino group and thioacetyl derivatives of 2-aminobenzo[d]imidazole are of particular interest in the search for new antitubulin fungicides.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140485530","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

Fast-activating reserve power sources: is lead dead indeed? 快速激活的后备电源：铅真的死了吗？

Chimica Techno Acta Pub Date : 2024-01-25 DOI: 10.15826/chimtech.2024.11.1.03

P. A. Shcheglov, Dmitry A. Samsonov, A. B. Pavlenkov, T. Kulova, Alexey Yu. Rychagov, A. Skundin, Evgeniya Yu. Postnova

{"title":"Fast-activating reserve power sources: is lead dead indeed?","authors":"P. A. Shcheglov, Dmitry A. Samsonov, A. B. Pavlenkov, T. Kulova, Alexey Yu. Rychagov, A. Skundin, Evgeniya Yu. Postnova","doi":"10.15826/chimtech.2024.11.1.03","DOIUrl":"https://doi.org/10.15826/chimtech.2024.11.1.03","url":null,"abstract":"The purpose of this research is to improve the performance and reduce the activation time of reserve power sources based on lead-acid systems at lower temperatures, down to –50 °C. Physico-chemical factors affecting the activation speed of reserve power sources based on Pb–HClO4–PbO2 and Zn–HClO4–PbO2 systems are investigated using chronopotentiometry, scanning electron microscopy, and standard contact porosimetry. Two approaches to the improvement of the low-temperature performance of power sources are used. The first one is based on the substitution of lead as anodic material with zinc. This allows the increase in discharge voltage and simultaneous decrease in activation time, but brings about the instability of discharge characteristics and, finally, deteriorates the reliability of power sources. The second approach is based on the use of PbO2 cathode material with enhanced nanoporosity. The chronopotentiometric method in galvanostatic mode is applied to the quality estimation of cathodes. The criterion of applicability of cathodes for reserve power sources consists in the low discharge overvoltage (0.1–0.2 V). Efficient performance of reserve power sources possessing the stable discharge voltage (1.5–1.8 V per cell) and the unprecedentedly short activation time (under 30 ms) even at lower temperatures (down to –50 °C) is achieved. The results are verified by fabrication and testing of pilot batches of miniaturized reserve power sources having microcells’ volume of 0.02 ml. The second approach to the improvement of power sources is transferred into the industrial production.","PeriodicalId":9964,"journal":{"name":"Chimica Techno Acta","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140495281","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