Pub Date : 2024-01-08DOI: 10.26534/kimika.v34i2.14-33
Jonathan Barcelo
Chemistry concepts are embedded in several contexts that are related to the future professional roles of pre-medical students. In the current academic landscape of pre-medical programs, an objective measurement of prior knowledge of chemistry concepts is necessary to promote students’ academic success. To address this issue, this study aimed to develop and validate the Prior Knowledge of Chemistry Concepts Test. This multiple-choice research instrument is designed to measure pre-medical students’ knowledge of essential chemistry concepts from pre-requisite chemistry courses in pre-medical programs in the Philippines. The final item pool, consisting of 26 general chemistry concepts and 21 general organic chemistry concepts was administered to 470 college students from four tertiary institutions in the Philippines. Item content validity indices (I-CVI) and kappa statistics guided initial revisions, while dichotomous Rasch analysis was utilized to determine the psychometric properties of the research instrument. The analysis provided evidence of adequate person and item reliability, item fit, local independence, and unidimensionality, although some items may be omitted in subsequent iterations. The application of the research instrument to assessment and evaluation was elaborated using the student ability and item difficulty logits along the person-item map. Suggestions for the improvement of the research instrument were also discussed.
{"title":"Development and Rasch Analysis of the Prior Knowledge of Chemistry Concepts Test for Pre-medical Students in the Philippines","authors":"Jonathan Barcelo","doi":"10.26534/kimika.v34i2.14-33","DOIUrl":"https://doi.org/10.26534/kimika.v34i2.14-33","url":null,"abstract":"Chemistry concepts are embedded in several contexts that are related to the future professional roles of pre-medical students. In the current academic landscape of pre-medical programs, an objective measurement of prior knowledge of chemistry concepts is necessary to promote students’ academic success. To address this issue, this study aimed to develop and validate the Prior Knowledge of Chemistry Concepts Test. This multiple-choice research instrument is designed to measure pre-medical students’ knowledge of essential chemistry concepts from pre-requisite chemistry courses in pre-medical programs in the Philippines. The final item pool, consisting of 26 general chemistry concepts and 21 general organic chemistry concepts was administered to 470 college students from four tertiary institutions in the Philippines. Item content validity indices (I-CVI) and kappa statistics guided initial revisions, while dichotomous Rasch analysis was utilized to determine the psychometric properties of the research instrument. The analysis provided evidence of adequate person and item reliability, item fit, local independence, and unidimensionality, although some items may be omitted in subsequent iterations. The application of the research instrument to assessment and evaluation was elaborated using the student ability and item difficulty logits along the person-item map. Suggestions for the improvement of the research instrument were also discussed.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"25 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139444868","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 : 2023-05-29DOI: 10.26534/kimika.v34i1.15-20
Jan-Michael Cayme, Aniano Jr. Asor, E. Miranda
Chemistry knowledge is fundamental in preserving and comprehending the tangible nature of museum collections. Despite chemistry’s importance in cultural heritage, a gap exists between the chemist’s knowledge and the accepted competencies of museum workers. This paper describes an initial study on introducing museum professionals with no formal scientific training in basic chemical thinking and research. A two-hour online session was conceived, comprising two separate lectures emphasizing the concepts, instrumental techniques, and example of a case study of an application of chemical analysis on a local heritage material. An open discussion and exchange of ideas followed the lectures. Feedback from the participants was very positive, and they described the online course as informative and valuable for their museum work. The qualitative evaluations obtained from this paper can serve as baseline information for developing a more extensive e-course in the future.
{"title":"Feasibility of An Introductory Chemistry for Cultural Heritage E-course for Museum Professionals in the Philippines","authors":"Jan-Michael Cayme, Aniano Jr. Asor, E. Miranda","doi":"10.26534/kimika.v34i1.15-20","DOIUrl":"https://doi.org/10.26534/kimika.v34i1.15-20","url":null,"abstract":"Chemistry knowledge is fundamental in preserving and comprehending the tangible nature of museum collections. Despite chemistry’s importance in cultural heritage, a gap exists between the chemist’s knowledge and the accepted competencies of museum workers. This paper describes an initial study on introducing museum professionals with no formal scientific training in basic chemical thinking and research. A two-hour online session was conceived, comprising two separate lectures emphasizing the concepts, instrumental techniques, and example of a case study of an application of chemical analysis on a local heritage material. An open discussion and exchange of ideas followed the lectures. Feedback from the participants was very positive, and they described the online course as informative and valuable for their museum work. The qualitative evaluations obtained from this paper can serve as baseline information for developing a more extensive e-course in the future.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83279669","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 : 2022-12-30DOI: 10.26534/kimika.v33i2.59-76
Gwyneth Rosal, Jhan Cromwell Aguinaldo, Lean Donnie Reyes, Gabriel Harold Casuat, Romalyn Balagtas, Erickson Del Mundo
Students perceive chemistry as a complex subject resulting in low academic performance. Education systems shall support students in bridging the gap between traditional learning and online set-up using technology-based materials. The Electronic Strategic Intervention Material (E-SIM) is a new learning method to help improve the learner’s performance in the least mastered competencies. This study focuses on determining how the E-SIM for “Ganyan Ang Bonding” (in English: Bonding Goes Like This) topic will improve the Grade 11 students’ knowledge about chemical bonding. The researchers used a one-group pretest-posttest control design. The population was pooled using simple random sampling and out of the randomly selected sections, twenty-two students were qualified after the voluntary response sampling. Pretest and posttest, which underwent validation, were given before and after the intervention respectively. The material was validated by experts prior to its utilization. The analysis showed a 0.01 normalized gain score, which is confirmed by the paired sample t-test with a result of -3.17 and p-value of 0.0023, hence presenting that there is a significant increase between the pretest and posttest scores. The student perception survey was used to further determine the efficiency of the material, which showed that the students perceived the E-SIM as an effective tool as review material.
学生认为化学是一门复杂的学科，导致学习成绩不佳。教育系统应支持学生利用基于技术的材料弥合传统学习和在线设置之间的差距。电子策略干预材料(E-SIM)是一种新的学习方法，旨在帮助学习者提高在最少掌握能力方面的表现。本研究的重点是确定“Ganyan Ang Bonding”(英语:Bonding Goes Like This)主题的E-SIM如何提高11年级学生对化学键的认识。研究人员采用了一组前测后测对照设计。总体采用简单随机抽样的方法，在随机选择的部分中，经过自愿抽样，有22名学生符合条件。干预前后分别进行前测和后测，并进行验证。该材料在使用前经专家验证。经分析，归一化增益得分为0.01，配对样本t检验结果为-3.17,p值为0.0023，证明前测与后测成绩有显著提高。通过学生感知调查进一步确定材料的有效性，结果表明学生认为E-SIM是一种有效的复习材料工具。
{"title":"Improving the Least Mastered Competencies of Grade 11 Students in General Chemistry using Electronic Strategic Intervention Material (E-SIM)","authors":"Gwyneth Rosal, Jhan Cromwell Aguinaldo, Lean Donnie Reyes, Gabriel Harold Casuat, Romalyn Balagtas, Erickson Del Mundo","doi":"10.26534/kimika.v33i2.59-76","DOIUrl":"https://doi.org/10.26534/kimika.v33i2.59-76","url":null,"abstract":"Students perceive chemistry as a complex subject resulting in low academic performance. Education systems shall support students in bridging the gap between traditional learning and online set-up using technology-based materials. The Electronic Strategic Intervention Material (E-SIM) is a new learning method to help improve the learner’s performance in the least mastered competencies. This study focuses on determining how the E-SIM for “Ganyan Ang Bonding” (in English: Bonding Goes Like This) topic will improve the Grade 11 students’ knowledge about chemical bonding. The researchers used a one-group pretest-posttest control design. The population was pooled using simple random sampling and out of the randomly selected sections, twenty-two students were qualified after the voluntary response sampling. Pretest and posttest, which underwent validation, were given before and after the intervention respectively. The material was validated by experts prior to its utilization. The analysis showed a 0.01 normalized gain score, which is confirmed by the paired sample t-test with a result of -3.17 and p-value of 0.0023, hence presenting that there is a significant increase between the pretest and posttest scores. The student perception survey was used to further determine the efficiency of the material, which showed that the students perceived the E-SIM as an effective tool as review material.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79832788","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 : 2022-11-03DOI: 10.26534/kimika.v33i2.1-20
Ma. Juryst Chelsea Armas, D. Apodaca
Polyhalogenated carbazoles (PHCZs) are persistent chemical pollutants increasingly detected in different environmental matrices. They are structurally and chemically similar to other persistent organic pollutants (POPs), which are capable of disrupting the endocrine systems. However, PHCZs such as 3-chloro-9H-carbazole (3-CCZ), 3-bromo-9H-carbazole (3-BCZ), and 36-dibromo-9H-carbazole (36-BCZ) are rarely discussed in the context of their adverse effects on human health. Using molecular docking to investigate the potential toxicity of these PHCZs with the human androgen receptor (AR), this study finds that 36-dibromo-9H-carbazole and 3-bromo-9H-carbazole are potential AR antagonists, with the former being more toxic than the latter. This finding is on account of the presence of both Asn705 and Thr877 in the hydrophobic interaction of 36-BCZ, while only Thr877 is found in the hydrophobic interaction of 3-BCZ. Hence, PHCZs with higher bromine substitutions are more likely to be endocrine disruptors. Moreover, their binding sites with the human androgen receptor are similar to that of the androgen (agonist). Therefore, this study suggests that PHCZs may readily penetrate and disrupt the human androgen receptor (AR), providing the groundwork for future research studies and experimental validation on the molecular docking employed.
{"title":"Predicting The Toxicity of Emerging Pollutants via Molecular Docking: Interaction of Polyhalogenated Carbazoles with Human Androgen Receptor","authors":"Ma. Juryst Chelsea Armas, D. Apodaca","doi":"10.26534/kimika.v33i2.1-20","DOIUrl":"https://doi.org/10.26534/kimika.v33i2.1-20","url":null,"abstract":"Polyhalogenated carbazoles (PHCZs) are persistent chemical pollutants increasingly detected in different environmental matrices. They are structurally and chemically similar to other persistent organic pollutants (POPs), which are capable of disrupting the endocrine systems. However, PHCZs such as 3-chloro-9H-carbazole (3-CCZ), 3-bromo-9H-carbazole (3-BCZ), and 36-dibromo-9H-carbazole (36-BCZ) are rarely discussed in the context of their adverse effects on human health. Using molecular docking to investigate the potential toxicity of these PHCZs with the human androgen receptor (AR), this study finds that 36-dibromo-9H-carbazole and 3-bromo-9H-carbazole are potential AR antagonists, with the former being more toxic than the latter. This finding is on account of the presence of both Asn705 and Thr877 in the hydrophobic interaction of 36-BCZ, while only Thr877 is found in the hydrophobic interaction of 3-BCZ. Hence, PHCZs with higher bromine substitutions are more likely to be endocrine disruptors. Moreover, their binding sites with the human androgen receptor are similar to that of the androgen (agonist). Therefore, this study suggests that PHCZs may readily penetrate and disrupt the human androgen receptor (AR), providing the groundwork for future research studies and experimental validation on the molecular docking employed.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75102110","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 : 2021-10-07DOI: 10.26534/kimika.v32i2.41-46
Yohannes Woldemariam, I. Villaseñor
Albizia lebbekoides (DC) Benth is one of the five species of the genus Albizia found in the Philippines. Not much is known about the chemistry and potential uses of this species. Solvent partition followed by sequential and repeated liquid chromatographic purification over silica led to the isolation of a compound from the hexane extract of A. lebbekoides leaves. A review of related literature and spectral analyses showed that the isolated compound is a new pentacyclic triterpenoid with an oleanane skeleton. Its structure was determined as 3β, 16α-dihydroxyolean-6(7),12(13)-dien-28-oic acid.
{"title":"A New Pentacyclic Triterpenoid from Albizia lebbekoides (DC) Benth (Leguminosae)","authors":"Yohannes Woldemariam, I. Villaseñor","doi":"10.26534/kimika.v32i2.41-46","DOIUrl":"https://doi.org/10.26534/kimika.v32i2.41-46","url":null,"abstract":"Albizia lebbekoides (DC) Benth is one of the five species of the genus Albizia found in the Philippines. Not much is known about the chemistry and potential uses of this species. Solvent partition followed by sequential and repeated liquid chromatographic purification over silica led to the isolation of a compound from the hexane extract of A. lebbekoides leaves. A review of related literature and spectral analyses showed that the isolated compound is a new pentacyclic triterpenoid with an oleanane skeleton. Its structure was determined as 3β, 16α-dihydroxyolean-6(7),12(13)-dien-28-oic acid.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86615356","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 : 2020-09-11DOI: 10.26534/kimika.v31i2.55-61
Dane Mykel M. Quiambao, A. Guidote, Rhodora F. Nicdao
This study aimed to reiterate the use of Chemistry demonstrations as effective teaching tools to students while addressing some of its drawbacks, which discourages teachers from doing them such as cost and safety. Four chosen existing Chemistry demonstrations (Blue Bottle Experiment, Copper Sulfate Experiment, Blown Away, Dancing Flames) were modified by using substitute reagents, which are more accessible, relatively safer, and at lower cost. These demonstrations were chosen based on how easily the substitute reagents will be obtained. Afterwards, with the permission of a private junior high school, they were presented to a group of Grade 9 students of their choosing. The students were asked to evaluate each demonstration using a Likert scale-based questionnaire. This questionnaire rates each demonstration in terms of aesthetics, the materials and procedure done, effectiveness to explain certain Chemistry topics, safety, and the students’ overall judgment regarding the use of demonstrations as teaching tools. By converting their evaluation to quantitative values, the demonstrations scored high in all major categories. With this, it is highly recommended to explore other Chemistry demonstrations for possible modifications, which can be integrated in lecture classes.
{"title":"Feasibility of Modifying Existing Chemistry Demonstrations by Using Substitute Materials","authors":"Dane Mykel M. Quiambao, A. Guidote, Rhodora F. Nicdao","doi":"10.26534/kimika.v31i2.55-61","DOIUrl":"https://doi.org/10.26534/kimika.v31i2.55-61","url":null,"abstract":"This study aimed to reiterate the use of Chemistry demonstrations as effective teaching tools to students while addressing some of its drawbacks, which discourages teachers from doing them such as cost and safety. Four chosen existing Chemistry demonstrations (Blue Bottle Experiment, Copper Sulfate Experiment, Blown Away, Dancing Flames) were modified by using substitute reagents, which are more accessible, relatively safer, and at lower cost. These demonstrations were chosen based on how easily the substitute reagents will be obtained. Afterwards, with the permission of a private junior high school, they were presented to a group of Grade 9 students of their choosing. The students were asked to evaluate each demonstration using a Likert scale-based questionnaire. This questionnaire rates each demonstration in terms of aesthetics, the materials and procedure done, effectiveness to explain certain Chemistry topics, safety, and the students’ overall judgment regarding the use of demonstrations as teaching tools. By converting their evaluation to quantitative values, the demonstrations scored high in all major categories. With this, it is highly recommended to explore other Chemistry demonstrations for possible modifications, which can be integrated in lecture classes.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74949670","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 : 2020-06-25DOI: 10.26534/kimika.v31i1.70-75
Jr. M. Guidote Armando
The SARS CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2), cause of COVID-19 (CoronaVirus Disease 2019) has afflicted close to 10 million people all over the world resulting to almost half a million deaths. This disease is severely contagious and necessitates social or physical distancing between persons. As such, traditional face-to-face learning is not advised and teachers need to shift to online teaching. There are challenges to online teaching and learning for students, teachers, and the higher education institute, e.g. hardware, bandwidth, and software issues. These will be difficult but these can be overcome eventually. This work is a personal account of the old normal or traditional way of teaching Organic Chemistry and the transition to the new normal of teaching on-line. On-line teaching can be as effective as traditional teaching but everyone has to put in effort and participate in training to get used to this. In the end, it is the teacher’s being a true teacher that matters, that the teacher teaches to the best of his or her ability even during this time of the COVID-19 pandemic.
{"title":"Teaching college chemistry in the time of COVID-19 pandemic: A personal account of teaching in the old normal vs. the new normal","authors":"Jr. M. Guidote Armando","doi":"10.26534/kimika.v31i1.70-75","DOIUrl":"https://doi.org/10.26534/kimika.v31i1.70-75","url":null,"abstract":"The SARS CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2), cause of COVID-19 (CoronaVirus Disease 2019) has afflicted close to 10 million people all over the world resulting to almost half a million deaths. This disease is severely contagious and necessitates social or physical distancing between persons. As such, traditional face-to-face learning is not advised and teachers need to shift to online teaching. There are challenges to online teaching and learning for students, teachers, and the higher education institute, e.g. hardware, bandwidth, and software issues. These will be difficult but these can be overcome eventually. This work is a personal account of the old normal or traditional way of teaching Organic Chemistry and the transition to the new normal of teaching on-line. On-line teaching can be as effective as traditional teaching but everyone has to put in effort and participate in training to get used to this. In the end, it is the teacher’s being a true teacher that matters, that the teacher teaches to the best of his or her ability even during this time of the COVID-19 pandemic.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"126 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74181335","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 : 2020-06-18DOI: 10.26534/kimika.v31i1.38-55
F. Sumera, Stephani Jacutin, Jan Michael Aficial, Aileen Filipino
A simple molecular descriptor based on molecular structure for predicting the boiling temperature (BT) of alkanes was developed in this paper. This topological index was used to correlate the boiling temperature of aliphatic hydrocarbons with their bond-valence substituent structure instead of by atom-to-atom branching framework. The predictive power of the bond-valence substituent index (BVSI) was evaluated by comparing it with the popular predictor in literature, the Randic index and the more recently proposed index, the Fi of Manso et al. (2012). The model developed through a second order regression of the plot of the alkane’s boiling temperature versus the BVSI index proved successful in its predictive power such that the method was also applied to a combination of aliphatic hydrocarbons, the alkanes, alkenes, alkynes and cycloalkanes. This topological index provided higher correlation with small deviations compared to the topological index used for comparison. A further study of the BVSI index can be explored for other organic compounds with different functional groups and other physical properties besides their boiling temperatures in the future.
提出了一种基于分子结构预测烷烃沸腾温度的简单分子描述符。该拓扑指数用于将脂肪烃的沸点温度与其键价取代基结构联系起来，而不是用原子-原子分支框架。通过将键价取代基指数(BVSI)与文献中流行的预测指标Randic指数和最近提出的指数Manso et al.(2012)的Fi进行比较，评估了BVSI的预测能力。该模型通过对烷烃沸腾温度与BVSI指数的二阶回归图开发，证明其预测能力是成功的，因此该方法也适用于脂肪烃、烷烃、烯烃、炔烃和环烷烃的组合。与用于比较的拓扑指数相比，该拓扑指数与小偏差的相关性更高。BVSI指数的进一步研究可以在未来探索其他具有不同官能团和其他物理性质的有机化合物的沸点温度。
{"title":"The Bond-Valence Substituent Index for Predicting the Boiling Temperatures of Aliphatic Hydrocarbons","authors":"F. Sumera, Stephani Jacutin, Jan Michael Aficial, Aileen Filipino","doi":"10.26534/kimika.v31i1.38-55","DOIUrl":"https://doi.org/10.26534/kimika.v31i1.38-55","url":null,"abstract":"A simple molecular descriptor based on molecular structure for predicting the boiling temperature (BT) of alkanes was developed in this paper. This topological index was used to correlate the boiling temperature of aliphatic hydrocarbons with their bond-valence substituent structure instead of by atom-to-atom branching framework. The predictive power of the bond-valence substituent index (BVSI) was evaluated by comparing it with the popular predictor in literature, the Randic index and the more recently proposed index, the Fi of Manso et al. (2012). The model developed through a second order regression of the plot of the alkane’s boiling temperature versus the BVSI index proved successful in its predictive power such that the method was also applied to a combination of aliphatic hydrocarbons, the alkanes, alkenes, alkynes and cycloalkanes. This topological index provided higher correlation with small deviations compared to the topological index used for comparison. A further study of the BVSI index can be explored for other organic compounds with different functional groups and other physical properties besides their boiling temperatures in the future.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"70 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79730680","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 : 2019-06-28DOI: 10.26534/kimika.v30i1.40-44
C. M. Ravidas, T. Villar, L. O. Namuco, H. Hernandez
The pericarp of Garcinia rubra, an endemic Garcinia species in the Philippines was extracted with dichloromethane. An isolate of the extract was acetylated giving monoacetyl and diacetyl derivatives. Analysis of these derivatives led to the elucidation of the xanthone 1,3,7-trihydroxy-2,4-bis(3-methylbut-2-enyl)-9H-xanthen-9-one. The compound was isolated and characterized through column chromatography, acetylation, FTIR, NMR and LCMS analyses.
{"title":"Isolation, Purification and Structure Elucidation of a Xanthone from the Pericarp of Kamandiis (Garcinia rubra Merr.)","authors":"C. M. Ravidas, T. Villar, L. O. Namuco, H. Hernandez","doi":"10.26534/kimika.v30i1.40-44","DOIUrl":"https://doi.org/10.26534/kimika.v30i1.40-44","url":null,"abstract":"The pericarp of Garcinia rubra, an endemic Garcinia species in the Philippines was extracted with dichloromethane. An isolate of the extract was acetylated giving monoacetyl and diacetyl derivatives. Analysis of these derivatives led to the elucidation of the xanthone 1,3,7-trihydroxy-2,4-bis(3-methylbut-2-enyl)-9H-xanthen-9-one. The compound was isolated and characterized through column chromatography, acetylation, FTIR, NMR and LCMS analyses.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"76 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79966053","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 : 2019-06-11DOI: 10.26534/kimika.v30i1.18-30
Joje Mar Perino Sanchez
This paper aimed to determine the indicators, which could contribute to the Chemistry achievement of selected Asian countries according to the data set provided by the 2015 Trends in Mathematics and Science Survey results. Educational data mining was employed to capture patterns, comparison and correlation among selected Asian countries (Hong Kong, Japan, Malaysia, Singapore, South Korea, Taiwan and Thailand) using TIMSS results in Chemistry and other Science domains achievements, learning resources, school climate, instructional considerations, and student affective aspects. This study found out that the average Chemistry achievement of the Asian countries was significantly higher than the world achievement. Through exploratory analysis, it was revealed that high achievers among the Asian countries have moderate to high perspective towards school climate, instructional considerations and student affective aspects, while those average or low achievers had high perspective towards the said factors. The study concluded that, out of the 15 factors included in the study, nine had positive correlation yet only prior achievement in Science, home educational resources, Science laboratory resources, computer use and prevalence of bullying could significantly determine the achievement of learners in Chemistry. Implications on spiral progression, resource allocation, safe, orderly and harmonious environments, and inspiring stories in instruction were derived for application in the Philippine context to maximize and enhance learning in Chemistry.
{"title":"Indicators of Asian Achievement in Chemistry: Implications to the Philippine Setting","authors":"Joje Mar Perino Sanchez","doi":"10.26534/kimika.v30i1.18-30","DOIUrl":"https://doi.org/10.26534/kimika.v30i1.18-30","url":null,"abstract":"This paper aimed to determine the indicators, which could contribute to the Chemistry achievement of selected Asian countries according to the data set provided by the 2015 Trends in Mathematics and Science Survey results. Educational data mining was employed to capture patterns, comparison and correlation among selected Asian countries (Hong Kong, Japan, Malaysia, Singapore, South Korea, Taiwan and Thailand) using TIMSS results in Chemistry and other Science domains achievements, learning resources, school climate, instructional considerations, and student affective aspects. This study found out that the average Chemistry achievement of the Asian countries was significantly higher than the world achievement. Through exploratory analysis, it was revealed that high achievers among the Asian countries have moderate to high perspective towards school climate, instructional considerations and student affective aspects, while those average or low achievers had high perspective towards the said factors. The study concluded that, out of the 15 factors included in the study, nine had positive correlation yet only prior achievement in Science, home educational resources, Science laboratory resources, computer use and prevalence of bullying could significantly determine the achievement of learners in Chemistry. Implications on spiral progression, resource allocation, safe, orderly and harmonious environments, and inspiring stories in instruction were derived for application in the Philippine context to maximize and enhance learning in Chemistry.","PeriodicalId":17914,"journal":{"name":"KIMIKA","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90046982","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：