STEM (Science, Technology, Engineering, and Mathematics) dan STEAM (Science, Technology, Engineering, Arts, and Mathematics) melawan CT (Computational Thinking) berperan penting dalam pembelajaran sains. Penelitian ini bertujuan untuk melihat penelitian terbarukan terkait pengaruh STEM dan STEAM terhadap kemampuan CT. Kajian dilakukan berdasarkan 3 tahapan metode Systematic Literature Review (SLR): identifikasi, prosedur penyaringan (pre-processing, abstract screening, dan text filtering), dan pemetaan data. Hasil kajian literatur diperoleh dari 12 artikel dengan distribusi terbanyak pada tahun 2020 (n=5), terindeks Scopus Q1 (n=9), menerapkan metode penelitian mixed methods (n=6), dan diterapkan pada jenjang pendidikan dasar (n =6). Kemudian, instrumen yang paling banyak digunakan adalah tes Computational thinking (n=6) pada dimensi-dimensi penting penilaian CT berupa problem solving, abstraction, algorithmic thinking, critical thinking, creative dan cooperative; terintegrasi dalam kegiatan berbasis proyek dengan model desain game (n=2), menghasilkan proyek terbanyak dalam bentuk robot (n=4), dan keseluruhan kegiatan pembelajaran STEM dan STEAM berdampak positif pada CT. Berdasarkan temuan tersebut, dapat disimpulkan bahwa kegiatan STEAM mampu memberikan efek yang lebih besar dibandingkan STEM karena adanya “Art”. dan keseluruhan kegiatan pembelajaran STEM dan STEAM berdampak positif pada CT. Berdasarkan temuan tersebut, dapat disimpulkan bahwa kegiatan STEAM mampu memberikan efek yang lebih besar dibandingkan STEM karena adanya “Art”. dan keseluruhan kegiatan pembelajaran STEM dan STEAM berdampak positif pada CT. Berdasarkan temuan tersebut, dapat disimpulkan bahwa kegiatan STEAM mampu memberikan efek yang lebih besar dibandingkan STEM karena adanya “Art”.
{"title":"STEM and STEAM Affects Computational Thinking Skill: A Systematic Literature Review","authors":"Suci Sukmawati Syafe'i, Hayuni Retno Widarti, I Wayan Dasna, Habiddin, Parlan, Surjani Wonorahardjo","doi":"10.17807/orbital.v15i4.18323","DOIUrl":"https://doi.org/10.17807/orbital.v15i4.18323","url":null,"abstract":"STEM (Science, Technology, Engineering, and Mathematics) dan STEAM (Science, Technology, Engineering, Arts, and Mathematics) melawan CT (Computational Thinking) berperan penting dalam pembelajaran sains. Penelitian ini bertujuan untuk melihat penelitian terbarukan terkait pengaruh STEM dan STEAM terhadap kemampuan CT. Kajian dilakukan berdasarkan 3 tahapan metode Systematic Literature Review (SLR): identifikasi, prosedur penyaringan (pre-processing, abstract screening, dan text filtering), dan pemetaan data. Hasil kajian literatur diperoleh dari 12 artikel dengan distribusi terbanyak pada tahun 2020 (n=5), terindeks Scopus Q1 (n=9), menerapkan metode penelitian mixed methods (n=6), dan diterapkan pada jenjang pendidikan dasar (n =6). Kemudian, instrumen yang paling banyak digunakan adalah tes Computational thinking (n=6) pada dimensi-dimensi penting penilaian CT berupa problem solving, abstraction, algorithmic thinking, critical thinking, creative dan cooperative; terintegrasi dalam kegiatan berbasis proyek dengan model desain game (n=2), menghasilkan proyek terbanyak dalam bentuk robot (n=4), dan keseluruhan kegiatan pembelajaran STEM dan STEAM berdampak positif pada CT. Berdasarkan temuan tersebut, dapat disimpulkan bahwa kegiatan STEAM mampu memberikan efek yang lebih besar dibandingkan STEM karena adanya “Art”. dan keseluruhan kegiatan pembelajaran STEM dan STEAM berdampak positif pada CT. Berdasarkan temuan tersebut, dapat disimpulkan bahwa kegiatan STEAM mampu memberikan efek yang lebih besar dibandingkan STEM karena adanya “Art”. dan keseluruhan kegiatan pembelajaran STEM dan STEAM berdampak positif pada CT. Berdasarkan temuan tersebut, dapat disimpulkan bahwa kegiatan STEAM mampu memberikan efek yang lebih besar dibandingkan STEM karena adanya “Art”.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139381377","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 : 2024-01-03DOI: 10.17807/orbital.v15i4.17709
Deni Ainur Rokhim, H. Widarti, Sutrisno Sutrisno
Initial knowledge and conception are one of the factors that have a major influence on learning activities. This is the basis for building students' knowledge of a material concept. However, not all students have the same ability, there are students who have low ability to build concepts. As a result, students who have low ability to build concepts may experience misconceptions that have an impact on their learning outcomes. Therefore, it is necessary to have an appropriate test instrument to identify misconceptions and multiple representation profiles especially in chemistry learning materials, one of which is the topic of reaction rate. This article aims to provide an overview of the application of the five-tier diagnostic instrument in identifying misconceptions and profiles of students' misconceptions about reaction rates. The method used is the SLR (Systematic Literature Review) from literature studies from 2011 to 2021 which are available in the ERIC, SINTA, and Google Scholar databases. The findings of the research results show that the five-tier test instrument can identify students' misconceptions about learning material. Information obtained from the use of the instrument can be used to determine the development of students' ability to understand chemistry using representations.
{"title":"Five-Tier Instrument to Identify Students' Misconceptions and Representation: A Systematic Literature Review","authors":"Deni Ainur Rokhim, H. Widarti, Sutrisno Sutrisno","doi":"10.17807/orbital.v15i4.17709","DOIUrl":"https://doi.org/10.17807/orbital.v15i4.17709","url":null,"abstract":"Initial knowledge and conception are one of the factors that have a major influence on learning activities. This is the basis for building students' knowledge of a material concept. However, not all students have the same ability, there are students who have low ability to build concepts. As a result, students who have low ability to build concepts may experience misconceptions that have an impact on their learning outcomes. Therefore, it is necessary to have an appropriate test instrument to identify misconceptions and multiple representation profiles especially in chemistry learning materials, one of which is the topic of reaction rate. This article aims to provide an overview of the application of the five-tier diagnostic instrument in identifying misconceptions and profiles of students' misconceptions about reaction rates. The method used is the SLR (Systematic Literature Review) from literature studies from 2011 to 2021 which are available in the ERIC, SINTA, and Google Scholar databases. The findings of the research results show that the five-tier test instrument can identify students' misconceptions about learning material. Information obtained from the use of the instrument can be used to determine the development of students' ability to understand chemistry using representations.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139388115","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 : 2024-01-03DOI: 10.17807/orbital.v15i4.19558
Volodymyr Tkach, Tetiana Morozova, V. Khrutba, Andrii Hlukhonets, Marta Kushnir, Y. Ivanushko, Viktor Kryvetskyi, Inna Kryvetska, I. Kryvetskyi, P. Yagodynets, M. Kucher, Z. Kormosh, Nadiia Chikun, Maria João Monteiro
For the first time, the theoretical description for cenobamate antiepileptic drug on anode, assisted by copper sulfide nanoparticles in alkaline medium, has been given. Two mechanisms, involving either tetrazolic ring, or the carbocyclic aromatic moiety, are possible for this process, reason why the concentration of the drug will be identified and quantified by two peaks. Despite of the mechanism hybrid nature, both of the peaks will produce an easy interpretable analytical signal, being thereby possible to confirm the efficiency of the electroanalytical signal.
{"title":"The Theoretical Description for Cenobamate CuS-Assisted Electrochemical Determination in Pharmaceutical Formulations and Wastewater","authors":"Volodymyr Tkach, Tetiana Morozova, V. Khrutba, Andrii Hlukhonets, Marta Kushnir, Y. Ivanushko, Viktor Kryvetskyi, Inna Kryvetska, I. Kryvetskyi, P. Yagodynets, M. Kucher, Z. Kormosh, Nadiia Chikun, Maria João Monteiro","doi":"10.17807/orbital.v15i4.19558","DOIUrl":"https://doi.org/10.17807/orbital.v15i4.19558","url":null,"abstract":"For the first time, the theoretical description for cenobamate antiepileptic drug on anode, assisted by copper sulfide nanoparticles in alkaline medium, has been given. Two mechanisms, involving either tetrazolic ring, or the carbocyclic aromatic moiety, are possible for this process, reason why the concentration of the drug will be identified and quantified by two peaks. Despite of the mechanism hybrid nature, both of the peaks will produce an easy interpretable analytical signal, being thereby possible to confirm the efficiency of the electroanalytical signal.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139389234","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 : 2023-10-13DOI: 10.17807/orbital.v15i3.18211
Kayna Hidalgo Zambrano, Carlos Delgado Villafuerte, Ernesto Rosero Delgado
Using residual biomass in biological processes is increasingly promoted to alleviate environmental impacts. However, the focus is mainly based on emerging technologies and limited resources, and the conditions of the technologies remain unclear. The objective of this research is to establish the conditions of a solid-state fermentation system (SSF) for the growth of fungal biomass and the production of ligninolytic enzymes of environmental interest using Aspergillus niger. In a screening step, the biomass and lipase enzyme expression of three A. niger strains obtained from different screening sites will be extended. In the second stage, the effect of packing density (ρs) and airflow (vvm) was evaluated through a 23, on the growth of fungal biomass, fiber degradation, and CO2 generation in a lipid-contaminated SSF system. The generation of biomass and the concentration of specific enzymatic activity (U/L) of lipase present a correlation for all the strains evaluated. It was estimated that the A. niger strain AN19bc isolated from sugarcane bagasse presents the highest accumulation of biomass and concentration of specific enzyme activity of lipase (0.027 U/L) after nine days. The most appropriate conditions for the production of fungal biomass of the AN19bc strain in an SSF system are presented with an airflow of 33.33 vvm and packing density ρs = 360 kg Mss/m3, levels with which Yx/s= 0.91 is reached. After the process, the solid support used in the SSF presents a change in composition, with the fiber being the component that suffers a considerable degradation of 78.70%.
{"title":"Effect of Solid-state Fermentation Parameters on Growth of Interest and Environmental Enzyme Production with Aspergillus niger","authors":"Kayna Hidalgo Zambrano, Carlos Delgado Villafuerte, Ernesto Rosero Delgado","doi":"10.17807/orbital.v15i3.18211","DOIUrl":"https://doi.org/10.17807/orbital.v15i3.18211","url":null,"abstract":"Using residual biomass in biological processes is increasingly promoted to alleviate environmental impacts. However, the focus is mainly based on emerging technologies and limited resources, and the conditions of the technologies remain unclear. The objective of this research is to establish the conditions of a solid-state fermentation system (SSF) for the growth of fungal biomass and the production of ligninolytic enzymes of environmental interest using Aspergillus niger. In a screening step, the biomass and lipase enzyme expression of three A. niger strains obtained from different screening sites will be extended. In the second stage, the effect of packing density (ρs) and airflow (vvm) was evaluated through a 23, on the growth of fungal biomass, fiber degradation, and CO2 generation in a lipid-contaminated SSF system. The generation of biomass and the concentration of specific enzymatic activity (U/L) of lipase present a correlation for all the strains evaluated. It was estimated that the A. niger strain AN19bc isolated from sugarcane bagasse presents the highest accumulation of biomass and concentration of specific enzyme activity of lipase (0.027 U/L) after nine days. The most appropriate conditions for the production of fungal biomass of the AN19bc strain in an SSF system are presented with an airflow of 33.33 vvm and packing density ρs = 360 kg Mss/m3, levels with which Yx/s= 0.91 is reached. After the process, the solid support used in the SSF presents a change in composition, with the fiber being the component that suffers a considerable degradation of 78.70%.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139319539","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 : 2023-10-12DOI: 10.17807/orbital.v15i3.18796
Volodymyr Tkach, Marta Kushnir, Iryna Korniienko, Yastremska Larysa, Olena Kuznetsova, Viktor Kryvetskyi, Inna Kryvetska, Igor Kryvetskyi, P. Yagodynets, Z. Kormosh, Dina Fedorova, Nadiia Chikun
For the first time, hydroxyquinol and sesamol electrochemical amperometric determination in tahini halva and lokum Turkish delights has been described. The electroanalytical process is given by amavadin-modified conducting polymer, in which both monomer and dopant may be natural compounds. Taking into account the ionic nature of the modifier, even in neutral medium the oscillatory behavior will be more probable in this system than in the simplest cases. Nevertheless, the amavadin-modified conducting polymer may be efficient electrode modifier for hydroxyquinol and sesamol electrochemical determination in Turkish delights like lokum and tahini halva.
该研究首次描述了用电化学安培法测定 tahini halva 和 lokum 土耳其美食中的羟基苯酚和芝麻酚。电分析过程由阿马凡定改性导电聚合物完成，其中的单体和掺杂剂都可能是天然化合物。考虑到改性剂的离子性质，即使在中性介质中，该系统的振荡行为也比最简单的情况更有可能发生。尽管如此，阿马凡定改性导电聚合物仍可作为有效的电极改性剂，用于测定土耳其美食（如 lokum 和 tahini halva）中的羟基苯酚和芝麻酚电化学含量。
{"title":"The Theoretical Description for Fructose Fermentation Product Hydroxyquinol and its Ether Sesamol Amperometric Determination in Tahini Halva and Lokum","authors":"Volodymyr Tkach, Marta Kushnir, Iryna Korniienko, Yastremska Larysa, Olena Kuznetsova, Viktor Kryvetskyi, Inna Kryvetska, Igor Kryvetskyi, P. Yagodynets, Z. Kormosh, Dina Fedorova, Nadiia Chikun","doi":"10.17807/orbital.v15i3.18796","DOIUrl":"https://doi.org/10.17807/orbital.v15i3.18796","url":null,"abstract":"For the first time, hydroxyquinol and sesamol electrochemical amperometric determination in tahini halva and lokum Turkish delights has been described. The electroanalytical process is given by amavadin-modified conducting polymer, in which both monomer and dopant may be natural compounds. Taking into account the ionic nature of the modifier, even in neutral medium the oscillatory behavior will be more probable in this system than in the simplest cases. Nevertheless, the amavadin-modified conducting polymer may be efficient electrode modifier for hydroxyquinol and sesamol electrochemical determination in Turkish delights like lokum and tahini halva.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139319839","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 : 2023-10-11DOI: 10.17807/orbital.v15i3.18358
Fairooz Ahmad Khan, Mushtaq Ahmad Bhat Mushtaq, Pathan Mohd Arif Arif, Mazahar Farooqui Mazahar
In the present investigation the adsorption behavior of methylene blue (MB) dye from aqueous solution onto untreated chinar leaves powder (CLP) and chinar leaves biochar (CLB) has been studied. To find out optimum conditions, adsorption process was carried out by varying different parameters such as contact time, adsorbent dose, concentration, temperature, salts, and pH. The equilibrium adsorption data were subjected to different popular isotherms (Langmuir, Freundlich, and Temkin) and kinetic models (pseudo-first order, pseudo-second order and intra-particle diffusion model). The thermodynamic study was also done on the adsorption process. The maximum monolayer adsorption capacities for MB dye onto given adsorbents are 1.53 mg/g (CLP) and 1.02 mg/g (CLB). Also the values of RL and n suggest favourable adsorption process of MB dye onto CLP and CLB adsorbents. The pseudo-second order kinetic model is best obeyed by both the mentioned adsorbents for MB dye adsorption with R2 value equal to 1. Thermodynamic study reveals that the adsorption process of MB dye is spontaneous, endothermic (CLB) and exothermic (CLP). At an equilibrium time of 20 min the uptake efficiency (> 99%) was recorded for both the low cost adsorbents (CLP and CLB) thus proved them fast and effective adsorbents for the removal of MB dye.
{"title":"A Comparative Study of Adsorption of Methylene Blue Dye onto Untreated Platanus orientalis (chinar tree) Leaves Powder and its Biochar - Equilibrium, Kinetic and Thermodynamic Study","authors":"Fairooz Ahmad Khan, Mushtaq Ahmad Bhat Mushtaq, Pathan Mohd Arif Arif, Mazahar Farooqui Mazahar","doi":"10.17807/orbital.v15i3.18358","DOIUrl":"https://doi.org/10.17807/orbital.v15i3.18358","url":null,"abstract":"In the present investigation the adsorption behavior of methylene blue (MB) dye from aqueous solution onto untreated chinar leaves powder (CLP) and chinar leaves biochar (CLB) has been studied. To find out optimum conditions, adsorption process was carried out by varying different parameters such as contact time, adsorbent dose, concentration, temperature, salts, and pH. The equilibrium adsorption data were subjected to different popular isotherms (Langmuir, Freundlich, and Temkin) and kinetic models (pseudo-first order, pseudo-second order and intra-particle diffusion model). The thermodynamic study was also done on the adsorption process. The maximum monolayer adsorption capacities for MB dye onto given adsorbents are 1.53 mg/g (CLP) and 1.02 mg/g (CLB). Also the values of RL and n suggest favourable adsorption process of MB dye onto CLP and CLB adsorbents. The pseudo-second order kinetic model is best obeyed by both the mentioned adsorbents for MB dye adsorption with R2 value equal to 1. Thermodynamic study reveals that the adsorption process of MB dye is spontaneous, endothermic (CLB) and exothermic (CLP). At an equilibrium time of 20 min the uptake efficiency (> 99%) was recorded for both the low cost adsorbents (CLP and CLB) thus proved them fast and effective adsorbents for the removal of MB dye.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139320559","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 : 2023-10-11DOI: 10.17807/orbital.v15i3.17993
Estela Moraes Nolasco, João Vitor dos Santos Da Silva, João Vitor Vieira De Paula, Fábio Luciano Caldas Da Silva, M. Leitão, Alessandra Silveira Antunes Araújo, Andreia de Oliveira Massulo, Amilcar Machulek Jr., Lucas De Melo da Silva
Parabens are used as preservatives in sanitizers and cosmetic products causing environmental concern, because presented potential as endocrine disrupters. Among these compounds, the most used are methylparaben and propylparaben. Thus, a study was proposed to evaluate the interaction between different concentrations (mmol L-1) of the variables methylparaben [MP] and propylparaben [PP], against the acute toxicity of the microcrustacean Artemia salina (A. salina) and Allium cepa (A. cepa) applying the 22 factorial design with an added center point. Responses were used: percent A. salina mortality (% mortality), A. cepa root growth inhibition (% root inhibition) and mitotic index (%MI). For A. salina, after 72 hours of exposure with the combination of concentration ([MP] and [PP] = 0.8 mmol L−1) caused an 80% mortality. While, A. cepa a high cytotoxicity was observed with the mixture of Parabens, exhibiting 72.3% root growth inhibition at [MP] = 1.2 mmol L-1 with [PP] = 1.2 mmol L-1. In contrast, for response %MI at [MP] = 0.3 mmol L-1 with [PP] = 0.3 mmol L-1, 2.5 %MI with 36% inhibition. In this context, parabens demonstrated high toxicity for A. salina and cytotoxicity for A. cepa, based on the interaction with the effect of the concentrations.
{"title":"Combined Toxicity of Methylparaben and Propylparaben in Artemia salina and Allium cepa Applying Experimental Design","authors":"Estela Moraes Nolasco, João Vitor dos Santos Da Silva, João Vitor Vieira De Paula, Fábio Luciano Caldas Da Silva, M. Leitão, Alessandra Silveira Antunes Araújo, Andreia de Oliveira Massulo, Amilcar Machulek Jr., Lucas De Melo da Silva","doi":"10.17807/orbital.v15i3.17993","DOIUrl":"https://doi.org/10.17807/orbital.v15i3.17993","url":null,"abstract":"Parabens are used as preservatives in sanitizers and cosmetic products causing environmental concern, because presented potential as endocrine disrupters. Among these compounds, the most used are methylparaben and propylparaben. Thus, a study was proposed to evaluate the interaction between different concentrations (mmol L-1) of the variables methylparaben [MP] and propylparaben [PP], against the acute toxicity of the microcrustacean Artemia salina (A. salina) and Allium cepa (A. cepa) applying the 22 factorial design with an added center point. Responses were used: percent A. salina mortality (% mortality), A. cepa root growth inhibition (% root inhibition) and mitotic index (%MI). For A. salina, after 72 hours of exposure with the combination of concentration ([MP] and [PP] = 0.8 mmol L−1) caused an 80% mortality. While, A. cepa a high cytotoxicity was observed with the mixture of Parabens, exhibiting 72.3% root growth inhibition at [MP] = 1.2 mmol L-1 with [PP] = 1.2 mmol L-1. In contrast, for response %MI at [MP] = 0.3 mmol L-1 with [PP] = 0.3 mmol L-1, 2.5 %MI with 36% inhibition. In this context, parabens demonstrated high toxicity for A. salina and cytotoxicity for A. cepa, based on the interaction with the effect of the concentrations.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139320621","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 : 2023-10-11DOI: 10.17807/orbital.v15i3.17906
B. Ankush, B. V. Shitole, N. V. Shitole
Glutamic acid is used as an efficient organocatalyst for one-pot synthesis of tetrahydrobenzo [b]pyran via condensation of an aromatic aldehyde, dimedone and malononitrile in ethanol: water (1:4) as solvent at reflux temperature. The short reaction time, cleaner reaction, and easy workup make this protocol practical and economically attractive.
{"title":"The Green and Efficient One-pot Synthesis of Tetrahydrobenzo[b]pyran Derivatives","authors":"B. Ankush, B. V. Shitole, N. V. Shitole","doi":"10.17807/orbital.v15i3.17906","DOIUrl":"https://doi.org/10.17807/orbital.v15i3.17906","url":null,"abstract":"Glutamic acid is used as an efficient organocatalyst for one-pot synthesis of tetrahydrobenzo [b]pyran via condensation of an aromatic aldehyde, dimedone and malononitrile in ethanol: water (1:4) as solvent at reflux temperature. The short reaction time, cleaner reaction, and easy workup make this protocol practical and economically attractive.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139320679","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 : 2023-10-08DOI: 10.17807/orbital.v15i3.17875
Kavirajaa Pandian Sambasevam, Nur Farahin Suhaimi, Izyan Najwa Mohd Norsham, Syed Shahabuddin, M. Raoov, S. Baharin
The present study demonstrates the self-assembly method of chemical oxidative polymerization of polypyrrole (PPy), polypyrrole/boron nitride (PPy/BN), and polypyrrole/dodecylbenzene sulfonic acid/boron nitride (PPy/DBSA/BN) thin films for ammonia (NH3) gas detection. The PPy, PPy/BN, and PPy/DBSA/BN thin films were comprehensively characterized using Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), X-ray diffractometry (XRD) and conductivity measurement. ATR-FTIR revealed all the pertinent peaks of PPy, BN, and DBSA present in the PPy/DBSA/BN. SEM images of PPy/DBSA/BN depict well-organized morphology. PPy/DBSA/BN recorded the highest conductivity of 4.771 x 10-6 S cm-1 among the prepared polymer thin films. The obtained characterization results are in good agreement with the NH3 gas sensor measurements conducted on the PPy/DBSA/BN composite. The linear correlation coefficient between the two was found to be R2 = 0.9916, indicating a strong relationship. Furthermore, the PPy/DBSA/BN thin film demonstrated a low limit of detection (LOD) of 5.8 ppm, surpassing the OSHA threshold value for NH3 gas. This suggests that the sensor is highly sensitive to trace amounts of NH3 gas. Moreover, the PPy/DBSA/BN thin film exhibited exceptional reusability, with the ability to be used for up to 10 cycles without a significant decrease in performance. The sensor also demonstrated selectivity towards NH3 gas in the presence of common interfering species. Additionally, it exhibited long-term stability, maintaining its performance over a period of 7 days. The proposed self-assembled gas sensor has showcased remarkable performance in detecting NH3 gas at room temperature, making it a promising candidate for industrial applications.
{"title":"Synthesis and Application of Polypyrrole/DBSA/Boron Nitride Ternary Composite as a Potential Chemical Sensor for Ammonia Gas Detection","authors":"Kavirajaa Pandian Sambasevam, Nur Farahin Suhaimi, Izyan Najwa Mohd Norsham, Syed Shahabuddin, M. Raoov, S. Baharin","doi":"10.17807/orbital.v15i3.17875","DOIUrl":"https://doi.org/10.17807/orbital.v15i3.17875","url":null,"abstract":"The present study demonstrates the self-assembly method of chemical oxidative polymerization of polypyrrole (PPy), polypyrrole/boron nitride (PPy/BN), and polypyrrole/dodecylbenzene sulfonic acid/boron nitride (PPy/DBSA/BN) thin films for ammonia (NH3) gas detection. The PPy, PPy/BN, and PPy/DBSA/BN thin films were comprehensively characterized using Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), X-ray diffractometry (XRD) and conductivity measurement. ATR-FTIR revealed all the pertinent peaks of PPy, BN, and DBSA present in the PPy/DBSA/BN. SEM images of PPy/DBSA/BN depict well-organized morphology. PPy/DBSA/BN recorded the highest conductivity of 4.771 x 10-6 S cm-1 among the prepared polymer thin films. The obtained characterization results are in good agreement with the NH3 gas sensor measurements conducted on the PPy/DBSA/BN composite. The linear correlation coefficient between the two was found to be R2 = 0.9916, indicating a strong relationship. Furthermore, the PPy/DBSA/BN thin film demonstrated a low limit of detection (LOD) of 5.8 ppm, surpassing the OSHA threshold value for NH3 gas. This suggests that the sensor is highly sensitive to trace amounts of NH3 gas. Moreover, the PPy/DBSA/BN thin film exhibited exceptional reusability, with the ability to be used for up to 10 cycles without a significant decrease in performance. The sensor also demonstrated selectivity towards NH3 gas in the presence of common interfering species. Additionally, it exhibited long-term stability, maintaining its performance over a period of 7 days. The proposed self-assembled gas sensor has showcased remarkable performance in detecting NH3 gas at room temperature, making it a promising candidate for industrial applications.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139321825","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 : 2023-09-12DOI: 10.17807/orbital.v15i3.19319
Paulo Marcos Donate
Gil Valdo José da Silva, from Guaimbê, São Paulo, rose above the constraints of his small-town upbringing. He moved to São Paulo in 1970 and graduated from the Antárctica Technical School with a degree in Industrial Chemistry. Initially employed by General Motors do Brasil, his zeal for knowledge drove him to pass the entrance exam at the University of S. Paulo's Chemistry Institute (IQ-USP) in 1975. Balancing studies and work, he taught chemistry in schools and developed a passion for teaching. Gil Valdo graduated in 1980 and went on to undertake doctoral studies in organic synthesis of natural goods. He was interested in research, particularly chemical synthesis and Nuclear Magnetic Resonance (NMR) techniques. His accomplishments went beyond the classroom; he became a licensed pilot, a Dive Master, and a lover of languages, culinary arts, and winemaking. Gil Valdo retired in December 2021, after more than 30 years at FFCLRP-USP, to pursue his passions more freely. He died on July 21, 2023, as a result of a heart attack. He was survived by a loving family and a legacy of intellectual, scientific, and cultural achievements. Gil Valdo José da Silva will be remembered for his serenity, dedication, and the diverse interests that enriched his life and the lives of those who were lucky enough to know him.
{"title":"GIL VALDO JOSÉ DA SILVA (1954-2023)","authors":"Paulo Marcos Donate","doi":"10.17807/orbital.v15i3.19319","DOIUrl":"https://doi.org/10.17807/orbital.v15i3.19319","url":null,"abstract":"Gil Valdo José da Silva, from Guaimbê, São Paulo, rose above the constraints of his small-town upbringing. He moved to São Paulo in 1970 and graduated from the Antárctica Technical School with a degree in Industrial Chemistry. Initially employed by General Motors do Brasil, his zeal for knowledge drove him to pass the entrance exam at the University of S. Paulo's Chemistry Institute (IQ-USP) in 1975. Balancing studies and work, he taught chemistry in schools and developed a passion for teaching. Gil Valdo graduated in 1980 and went on to undertake doctoral studies in organic synthesis of natural goods. He was interested in research, particularly chemical synthesis and Nuclear Magnetic Resonance (NMR) techniques. His accomplishments went beyond the classroom; he became a licensed pilot, a Dive Master, and a lover of languages, culinary arts, and winemaking. Gil Valdo retired in December 2021, after more than 30 years at FFCLRP-USP, to pursue his passions more freely. He died on July 21, 2023, as a result of a heart attack. He was survived by a loving family and a legacy of intellectual, scientific, and cultural achievements. Gil Valdo José da Silva will be remembered for his serenity, dedication, and the diverse interests that enriched his life and the lives of those who were lucky enough to know him.","PeriodicalId":19680,"journal":{"name":"Orbital: The Electronic Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139340644","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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