cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
-
Contact Email
-
Phone
-
Journal Mail Official
-
Editorial Address
-
Location
Kota surakarta,
Jawa tengah
INDONESIA
JKPK (Jurnal Kimia dan Pendidikan Kimia)
Published by Universitas Sebelas Maret
ISSN : 25034146     EISSN : 25034154     DOI : -
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry
The JKPK (Jurnal Kimia dan Pendidikan Kimia) is a national journal, published three times a year in April, August, and December, containing research articles on Chemistry and Chemistry education.
Arjuna Subject : -
Articles 114 Documents
 1   2   3   4   5 
Characterization of Biocomposites from Polylactic Acid and Cellulose of Oil Palm Empty Fruit Bunch Paramitha, Tika; Sitompul, Johnner P
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 5, No 3 (2020): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v5i3.39212

Abstract

Biocomposites are polymers reinforced with natural fibers, such as cellulose. This research aims to synthesize cellulose from Oil Palm Empty Fruit Bunch (OPEFB) and biocomposites from PLA and cellulose. In this study, cellulose was obtained through alkalization, hydrolysis, and bleaching of OPEFB. Biocomposites production was carried out by mixing PLA and cellulose using the extrusion method. In the extrusion method, PLA and cellulose of OPEFB were mixed using an extruder above the melting point of PLA of 170°C. The output product of an extruder was then pressed using a compression moulding machine to form biocomposites. The tensile strength of biocomposites had a smaller value than pure PLA, whereas the modulus young of biocomposites with 5% by weight of cellulose had a higher value than pure PLA. The decrease in the mechanical properties of biocomposites was caused by poor adhesion between PLA and cellulose. The water absorption of biocomposites was greater than pure PLA, which was influenced by cellulose's characteristics as hydrophilic and PLA is hydrophobic. Also, the higher water absorption in biocomposites accelerated the weight loss of biodegradability.
Analysis of The Nature of Science in Chemistry Textbooks on The Topic Acid-Base Equilibrium: a Content Analysis Rahmah, Aulia; Ariani, Sri Retno Dwi; Mulyani, Bakti
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 7, No 3 (2022): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v7i3.65094

Abstract

This study was conducted to describe aspects of the Nature of Science (NoS), its presentation, and its scores from chemistry textbooks used in Surakarta on acid-base equilibrium topics. This research was qualitative research with a content analysis method. Three high school chemistry textbooks for class XI from different publishers were analyzed by two raters based on ten aspects of the NoS. Interrater reliability was calculated using the cohen Kappa. The results showed that a scientific law is the only aspect that is not included in the three textbooks A, B, and C. Other aspects of NoS contained in textbooks A and B are slightly different from textbook C. Textbooks A and B contain the same aspects: empirical, inferential, creative, theory-driven, tentative, scientific methods, scientific theories, social science, and the application of science in socio-cultural, while textbook C does not contain tentative and theory-driven aspects. The implicit-correct category dominates the presentation of the NoS aspects in the textbooks. Presentations with implicit-incorrect and explicit-incorrect categories were not found in this study. The scores obtained by textbooks A, B, and C based on the presentation of aspects of NoS are 9, 11, and 8, respectively, of the maximum total score that can be obtained of 30. It did not show the presence of the NoS aspects explicitly, correctly, consistently, and completely, so textbooks containing NoS explicitly are required. Teachers also need to guide students in interpreting NoS in learning. 
Analysis of Students’ Critical Thinking Skills by Applying Flipped Classroom Learning Model using Powtoon Application on The Topic of Salt Hydrolysis Paristiowati, Maria; Nanda, Elsa Vera; Putri Hasibuan, Nur Azizah; Ilmana, Miska Zidna
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 7, No 3 (2022): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v7i3.67802

Abstract

This study aims to determine students' critical thinking skills by applying flipped classrooms using the Powtoon application on the topic of salt hydrolysis. This study, which included 36 participants—15 men and 21 women—used a descriptive methodology and was carried out at one of Jakarta's public high schools. The instrument used was an observation sheet to observe the flipped classroom model’s learning process, critical thinking skills tests, reflective journals, and depth interviews. The flipped classroom method entails four steps: pre-class by studying independently and providing stimuli. In-class by fostering critical thinking; and post-class by evaluating. Combining asynchronous and synchronous activities was the process. Students learn independently during the pre-class stage by answering pre-learning questions and watching videos. During the class phase, Zoom meetings are used for synchronous learning to discuss salt hydrolysis applications in particular contexts. Discussion assignments on the salt hydrolysis case help students learn asynchronously after class. The study results showed that the flipped classroom using the Powtoon application can be an alternative for distance learning and can influence the students’ critical thinking at a very good level. It also helps them be more active and critical in learning, like exchanging opinions with others and doing assignments on the topic of salt hydrolysis.
Analysis Thin Film Polymer Composite of Polymethyl Metacrylate-Reactive Mesogen Diacrylate and its Conductivity Properties Afrizal, Afrizal; Budi, Setia; Ambarwati, Annisa; Riswoko, Asep
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v8i1.72492

Abstract

This study aimed to investigate the impact of temperature during the UV curing process on the formation of a thin film polymer composite composed of polymethyl methacrylate-reactive mesogen diacrylate. The thin film polymer composite was successfully synthesized using the UV curing method, and the reactive mesogen diacrylate employed in this study was RM 82. Methyl methacrylate and RM 82 were polymerized through UV curing with photopolymerization additions using Benzoyl Peroxide as the initiator. The photopolymerization process was performed at various temperatures of 125℃, 150℃, and 200℃ for 5 minutes. The thin film photopolymerized at 125℃ and 150℃ exhibited greater transparency than the thin film photopolymerized at 200℃. The FTIR results indicated the breakdown of the vinyl group and the triple bond. The FTIR spectrum displayed successful polymerization, with peak wave numbers of 1147 cm-1 and 1221 cm-1 for PMMA in the presence of C-O-C in the ester and a peak at 1465 cm-1. The SEM results demonstrated that the thin film photopolymerized at 200℃ had become distorted. The XRD results revealed that the thin films of all variations were semi-crystalline. Meanwhile, the conductivity test revealed that the thin film photopolymerized at 125℃ had a conductivity value of 2.095 x 10-12 S, while the photopolymerized thin film at 150℃ had a conductivity of 2.14 x 10-12 S. Hence, the addition of reactive mesogen RM82 by 50% may increase the conductivity value of the thin film, making it a potential material for applications as a thin film polymer composite of PMMA-RM 82.
Laminarin crude extract characterization of Sargassum sp. originated from Jepara-Indonesia with Laminarin Acid Extraction method using acetic acid solvent Sari, Ratna Indria; Suryati, Suryati; Amalia, Indrian Rizka; Taslihan, Arief
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v8i1.72313

Abstract

Laminarin is a bioactive compound found in Sargassum sp. whose existence is widespread in Indonesia, including in Jepara, Central Java, Indonesia. Laminarin can be used in food, pharmaceutical, cosmetic, and feed industries as it is beneficial as an anti-inflammatory, antioxidant and regulates gut microbiota. This study aimed to extract laminarin from Sargassum sp. that originated from Jepara-Indonesia by laminarin acid extraction procedure with an acetic acid solvent (CH3COOH) which was safer, cheaper and easy to obtain. Characterization of laminarin crude extract use Fourier Transform Infrared (FT-IR); meanwhile, nutrition tested are moisture, ash, crude protein and crude fiber content. The results showed that laminarin extraction of Sargassum sp. from Jepara using acetic acid solvent (L-ACT) obtained the highest yield of 15.5% with a solvent ratio of 1:5 (w/v) but still lower than the yield extraction using hydrochloric acid (L-HCl) with a solvent ratio of 1:10 (w/v) that was 24.17%. FT-IR absorption band at 2359.96 cm-1 (-OH bending; transmission angle peak), 1538.54 cm-1 (C-C aromatic; carboxyl groups), 1409.35 cm-1 (C-H bending; carboxyl groups), 1230.89 cm-1 (C-O-C stretching; sugar region), 1022.58 cm-1 (R-O-R (acetal)), and at 944.94 cm-1 (O-R cyclic) of the L-ACT samples were similar to those of the L-HCl and standard laminarin references in other studies that used as a positive control, confirming the presence of laminarin. The L-ACT extract had lower ash, crude protein content and higher water content compared to L-HCl crude extract. Meanwhile, the crude fiber content in both L-ACT and L-HCL was not identified. The results showed that Sargassum sp. from Jepara was the potential source of laminarin for many industries (pharmacy, cosmetic, food), and acetic acid could be used as a suitable solvent to extract laminarin in the LAE method. 
pH-Sensitive Strips Based on Cellulose and Anthocyanins from Dried Java Plum Fruits (Syzygium cumini) Wathon, Muhammad Hizbul; Susilowati, Endang; Ariani, Sri Retno Dwi
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v8i1.72702

Abstract

This study aimed to develop pH-sensitive strips made of cellulose incorporated with anthocyanins extracted from dried Java plum fruits (Syzygium cumini) which potentially can be used to monitor food freshness. The spoilage of animal protein typically produces total volatile basic nitrogen (TVB-N), which can be easily detected using pH-sensitive indicators. pH-sensitive indicators can be developed by combining biopolymers and anthocyanins. Biopolymers were cellulose from Whatman filter paper. While anthocyanins in this study were extracted from dried Java plum fruits (Syzygium cumini) with acidified water (0.01% v/v HCl) followed by SPE. Anthocyanins were incorporated into Whatman filter paper and dried at 70 °C for 10 min. Cellulose incorporated with anthocyanins was analysed using FT-IR and tested for pH 7-10. LC-MS spectra showed cyanidin-3-O-glucoside (m/z 449.3), delphinidin-3-O-glucoside (m/z 465.3), and petunidin-3-O-glucoside (m/z 479.3). These anthocyanins were the products of the deglycosylation of anthocyanin diglycosides. The deglycosylation of anthocyanins takes place through two different routes in either hemiketal or quinonoid forms. Those proposed two pathways are through protonation on an oxygen atom connecting an aglycone and a sugar moiety or through protonation on an oxygen atom within a sugar ring moiety. UV-Vis studies showed the colour profiles of anthocyanins in buffer solutions pH 1-12. The λvis-max of flavylium at pH < 3 ranged from 515-524 nm. At pH 4 to 6, colourless hemiketal was observed. The λvis-max of the quinonoid base was 575 nm at pH 7 and 590-599 nm for quinonoid anion at pH > 8. In alkaline pH, chalcone was observed.
Profiling GC-MS Ethanol Extract of Putri Malu Leaves (Mimosa pudica L.) and Its Potential as Anti Cholesterol In Vitro Adhityasmara, Dhimas; Indriyanti, Erwin; Ramonah, Dewi; Elisa, Novi
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v8i1.66685

Abstract

Cholesterol plays a crucial role in cell building and hormone production in the body, but excessive levels can lead to various diseases. Elevated cholesterol levels increase the risk of cardiovascular diseases such as atherosclerosis. Natural remedies for high cholesterol treatment are commonly sourced from medicinal plants containing many phytochemicals. One such plant is the Putri Malu (Mimosa pudica L.) leaf. This study aims to evaluate the chemical composition of Putri Malu leaf extract and its potential anti-cholesterol effects in vitro. The extraction process used in this study was maceration, followed by GC-MS profiling analysis and the Liebermann Burchad method with UV-Vis spectrophotometry. The findings of this study revealed the presence of five chemical constituents in the extract. Among them, the second and fourth peaks had the highest abundance of acacetin at 14.08% and diosmetin at 73.79%, respectively. The ethanol extract of Putri Malu leaves demonstrated strong anti-cholesterol activity in vitro with an IC50 value of 24.8993, indicating its potential as an agent for treating hypercholesterolemia. Further research is required to evaluate this extract's efficacy in vivo and investigate its underlying mechanism of action.
Synthesis and Photocatalytic Activity Test of Bi-TiO2 toward Humic Acid Degradation under Visible Light Irradiation Dien, Efraime Caroline; Aritonang, Anthoni Batahan; Gusrizal, Gusrizal
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v8i1.71525

Abstract

Humic acid (HA) in water can harm humans if it is regularly used or consumed. HA causes problems in the water, such as color, taste, and the formation of metal complexes. Therefore, it is necessary to degrade HA to address these problems. In this study, HA degradation was carried out using bismuth-doped TiO2 (Bi-TiO2) as a photocatalyst. The effect of Bi-TiO2 synthesized at various Bi concentrations and calcination temperatures on HA degradation was investigated and compared to pristine TiO2. Bi-TiO2 was synthesized via the sol-gel method and characterized using X-Ray Diffraction (XRD), Diffuse Reflectance Spectroscopy UV-Visible (DRS UV-Vis), and Fourrier Transform-Infra Red (FT-IR) Spectroscopy. The XRD analysis showed that the optimum calcination temperature was 500oC, with the highest crystallinity index (62.04%) and smallest crystallite size (11.95 nm). The DRS UV-Vis analysis showed that Bi-TiO2 1.5% led to the lowest band gap of 1.59 eV (λ = 782.33 nm), indicating that the photocatalyst was active under visible light irradiation. The FT-IR analysis showed an adsorption peak from the Bi-O bond at 802.39 cm-1, which caused a shift in the Ti-O-Ti adsorption peak. The photodegradation test was conducted using a 30 mL volume of HA solution 50 ppm and a 50 mg mass of catalyst. The results showed that Bi-TiO2 1.5% exhibited the highest efficiency in degrading HA, achieving 68.54% under visible light irradiation for 180 minutes. These results suggest the potential of Bi-TiO2 as an alternative method for treating HA in peat water using visible light irradiation. 
Effectiveness of Virtual STEM Laboratories for Enhancing High School Students' Creativity and STEM Literacy Rahmadani, Nurul Fitri; Ariani, Sri Retno Dwi; Mulyani, Sri; Indriyanti, Nurma Yunita
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v8i1.64548

Abstract

The Virtual STEM Laboratory is a contextual experimental simulation learning tool that integrates science, technology, engineering, and mathematics (STEM) concepts. This study aims to investigate the Virtual STEM Laboratory's effectiveness in enhancing high school students' STEM literacy and creativity. STEM literacy is defined as the ability of a student to apply, identify, and integrate STEM concepts to solve complex problems and innovate in various areas. Meanwhile, creativity refers to the capability to generate novel and valuable ideas or solutions. The study used an experimental design with a control group to compare the effectiveness of the Virtual STEM Laboratory. In addition, students' STEM literacy and creativity were measured using posttest scores. The results showed that the experimental group had higher STEM literacy and creativity scores compared to the control group, which indicates the effectiveness of the Virtual STEM Laboratory. The study found that the Virtual STEM Laboratory improved STEM literacy as measured by the independent t-test and Kruskal Wallis test with a significance value of 0.000. This suggests that the experimental group had better STEM literacy skills than the control group. The Virtual STEM Laboratory was also found to be effective in enhancing student creativity as measured by the independent t-test with a significance value of 0.000, which implies that the experimental group generated more novel and valuable ideas than the control group. The study confirms the Virtual STEM Laboratory's effectiveness in enhancing high school students' STEM literacy and creativity. The Virtual STEM Laboratory is a valuable tool that can improve students' STEM literacy and creativity, thus contributing to their academic and professional development. Further studies can be conducted to explore the potential of the Virtual STEM Laboratory in enhancing other aspects of STEM education. 
The Effect of Testing Chamber on the Response Patterns of an array of Gas Sensor in Sensing Robusta Coffee Aroma from Bangsalsari and Sidomulyo, Jember Asnawati, Asnawati; Siswoyo, Siswoyo; Ningsih, Febiola Silvia; Ainiyah, Qurotul; Zulfikar, Zulfikar; Mulyono, Tri; Muflihah, Yeni Maulidah
JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia)
Publisher : Program Studi Pendidikan Kimia FKIP Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jkpk.v8i1.68520

Abstract

The gas sensor performance can be improved by optimizing the testing chamber design, including volume, shape, gas inlet/outlet positions, and sensor array. We studied the effect of chamber design on the gas sensor's response patterns characteristics in differentiating Robusta coffee aroma from Sidomulyo, and Bangsalsari, Jember. Hemisphere and cylindrical chambers, with three variations for each model, and a ring chamber, were used as model chambers. Eight types of gas sensors (MQ-135, MQ-136, MQ-2, MQ-3, MQ-6, MQ-7, MQ-8, and MQ-9) were used in the sensor array system to examine the gas sensor instrument performance. The resulting responses were analyzed using the reproducibility, response time, and principal component analysis (PCA) test. The result shows that the reproducibility value for all hemisphere chamber models, cylindrical chamber model-1, and ring chamber indicated an excellent sensor performance (%RSD<20%). Meanwhile, the cylindrical chambers model-2 and 3 resulted in %RSD>20%, indicating the low performance of the gas sensor. Among all variations, hemisphere chamber model-1, a hemisphere chamber with the inlet position lower than the outlet gas position, has the best performance due to the shortest response time, high-intensity signal, and performing ability to distinguish the response patterns characteristics of Robusta coffee aroma from Sidomulyo and Bangsalsari, Jember, Indonesia. In this study, we found that changing the testing chamber design, volume, and inlet/outlet position resulting different gas sensor responses to the coffee aroma. The proposed instrument can distinguish the coffee aroma from a different origin.

Page 1 of 12 | Total Record : 114

 1   2   3   4   5 

Filter by Year

2020 2026


Reset
Filter By Issues
All Issue Vol 11, No 1 (2026): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 10, No 3 (2025): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 10, No 2 (2025): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 10, No 1 (2025): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 9, No 3 (2024): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 9, No 2 (2024): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 9, No 1 (2024): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 3 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 2 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 8, No 1 (2023): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 7, No 3 (2022): JKPK (Jurnal Kimia dan Pendidikan Kimia) Vol 5, No 3 (2020): JKPK (Jurnal Kimia dan Pendidikan Kimia) More Issue