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This study aims to measure students' ability in creative thinking on the subject matter of elasticity Hooke law through statistic descriptive using the Rasch model. The students' creativity is determined by logit parameter providing a similar scale. The instrument used was an essay test developed from Torrance indicators. This research involved 35 students including 17 females and 18 males who had prior knowledge about this subject. To obtain the objective, firstly, the analysis of validity and reliability items was conducted for the instrument. The construct validity was obtained by Mean Square (MNSQ) values, and reliability was determined by three indicators including person reliability, item reliability, and alpha Cronbach values. The results of the analysis show that the instrument having been tested is valid because the MNSQ values are in the accepted range which infit and outfit person values are 0,97 and 1,02 as well as infit and outfit item values are 0,98 and 1,02, and the instrument is also reliable in good criteria with 0,83 value. The analysis of person reliability and item reliability shows that the students' answers are consistent and the quality of questions is good namely 0,83 and 0,89, respectively. Furthermore, the logit value indicates that there is a tendency of students having a lower ability than the difficulty level of the questions. This implies that the teachers should put more effort to improve creative thinking students in further learning activities as the creative thinking skill is important to prepare students in their future career. Also, the instrument developed can be utilized to measure creative thinking skill in the similar subject matter. [ABSTRACT FROM AUTHOR]

Currently, the researchers have been focused on optimizing the materials for gas sensing applications such as ethanol gases. In this work, we reported the characterization of thick film ceramics composite based on Fe2O3-LaFeO3-La2O3 doping 3 mol% Gd that was prepared by coprecipitation method. The thick film ceramics were fabricated using a screen printing technique. Then, to verify the performance of the thick film ceramics, the characterization has been conducted such as x-ray diffraction (XRD), scanning electron microscopy (SEM) and electrical properties using gas chamber tools. XRD characterizations show that the crystal structure has two phases i.e. cubic for LaFeO3 and hexagonal for Fe2O3 and La2O3. Furthermore, SEM characterization informed that the average grain size of the materials is 0.41 µm. The last, electrical properties showed that the materials had a response of about 0.28 to 0.77 in 100 to 300 ppm ethanol gases. This information indicated that the Fe2O3−LaFeO3-La2O3 has a potential to be applied as material gas sensors, especially for ethanol gases. [ABSTRACT FROM AUTHOR]

This study aims to interpret the inventory of critical thinking skills of high school students in online learning during the Covid-19 pandemic on momentum and impulse materials in Subang Regency. This research is quantitative descriptive. The sample in this study amounted to 91 high school students who selected using purposive sampling technique. The data analysis technique used is descriptive statistics. The instrument used consisted of 10 multiple choice questions which were developed based on indicators of critical thinking skills according to Ennis. The results showed that students' critical thinking skills in the elementary clarification aspect had a percentage of 47.99% in the medium category, the basic support aspect 32.42% in the low category, the inference aspect 39.93% in the low category, the advance clarification aspect had 23.08 % with low category and strategy and tactics aspect 43.96% with medium category. Overall, the percentage of critical thinking skills of high school students in Subang Regency when learning online is 37.48%. Statistical results show that the Asymp.Sig value is 0.893>0.05, which means that there is no significant difference between the critical thinking skills of male students and female students. The conclusion, the critical thinking skills of high school students towards momentum and impulse material in online learning during the Covid-19 pandemic in Subang Regency are still in the low category. Therefore, it is necessary to make efforts especially during the Covid-19 pandemic to improve the critical thinking skills of high school students regarding momentum and impulse materials. [ABSTRACT FROM AUTHOR]

This study aimed to develop and determine the feasibility of an interactive multimedia-based android application (mB-Physics) on Newton's Law of Gravity. This study was included in research and development (R&D) study using the ADDIE development model (Analysis, Design, Development, Implementation, and Evaluation). The research instruments employed included material expert validation sheets, validation questionnaires for media experts and teachers' perceptions, as well as students' conception sheets. The result of application assessment by material experts indicated that the suitability indicator percentage with the overall material description was 88% with the very appropriate category. Moreover, assessment of application by media experts obtained an average percentage of 96% included as very good category. The application assessment by 10 Physics teachers acquired an average percentage of 84% considered as good category and by 40 students' responses obtained an average percentage of 83% or high criteria (independent). Based on the results of the study, it can be stated that the mB-Physics application is suitable to be used to support learning Newton's Law of Gravity in grade X Natural Science major in senior high schools. [ABSTRACT FROM AUTHOR]

This study aims to evaluate representational competence on the concepts of momentum and impulse of high school students in distance learning during the Covid-19 pandemic. This research is also an attempt to find information on whether there are differences in representation competence in schools with different zoning. This study uses a quantitative descriptive method. Sampling using cluster sampling technique, the number of samples as many as 517 high school students. The instrument used was a multiple choice question with a total of 12 questions. The data were analyzed statistically to determine the percentage of representational competence and to determine the difference in representational competence of the two schools. The results of data analysis show that all students' representational competence is at a moderate level, which means that 44% of students have representational competence. Statistical results show that there are differences in the representation competence of high school students between the urban zone and the district zone, this can be seen from the score the Asymptotic Significance 0.000<0.05. This difference can occur because high school students in urban zones have easy facilities to practice representation competence, seen from the ease of high school students in accessing the internet network to solve problems contained in physics concepts, one of which is momentum and impulse. [ABSTRACT FROM AUTHOR]

TiO2 nanoparticles have been coated on the polypropylene (PP) copolymers using a milling method with temperature controller modification. These experiments were carried out at different milling temperature: 100 °C, 110 °C, 120 °C and 130 °C for 90 minute milling time for each experiment. Photocatalytic degradation of methylene blue (MB) was investigated using TiO2 coated PP copolymer which floats on the MB solution and illuminated under sunlight for 36 hours. It was found that TiO2 coated PP polymer at temperature of 100 °C resulted in optimum decomposition of MB solution. The concentration of MB in a test solution after 18 hours of exposure to the sun was 15.42%. The reaction rate constants (k) and the half-reaction (t1/2) in the MB photodegradation using the catalysts with a coating temperature of 100 °C, are 0.106 hours-1 and 6.53 hours, respectively. This coated material is very potential for repeated use to purify bulk water in high sunlight intensity region. [ABSTRACT FROM AUTHOR]

Silicon nanowire (SiNW) deposition can be performed by introducing Si precursor onto metal catalyzed substrate as a lead on vapor-liquid-solid (VLS) mechanism. Nanosize metallic droplet as catalyst can be synthesized by annealing a very thin metallic film in order to break it into droplet. The simple method had been used for synthesizing Platinum (Pt) nano-droplet. A very thin Pt film had been grown on a wafer silicon substrate using fine coat ion sputtering followed by annealing in which the temperature varied in the interval of 700-800° C, each for 30 minutes. The surface morphology of the film was done by scanning electron microscope (SEM) which showed that Pt nano-droplet in the best formation obtained at the annealing temperature of 800° C. In addition, dependences of the film thickness and annealing time to produce Pt nano-droplet formation, especially the nano-droplet size, had been investigated. [ABSTRACT FROM AUTHOR]

The transparent conductive coating based on carbon nanotubes (CNTs) had been fabricated using the electric field deposition method. The scanning electron microscope (SEM) results show a quite uniform CNTs on Corning glass substrates. Moreover the X-ray Diffraction (XRD) results shows the peak at around 25° which proves the existence of CNT materials. The CNT thin films obtained with different deposition times have different transmittance coefficients at wavelength of 550 nm. I-V measurement results shows higher sheet resistance value which relates with bigger transmittance coefficients and vice versa. [ABSTRACT FROM AUTHOR]