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Photoelectrochemical (PEC) is a new renewable energy technology that converts H2O into hydrogen and oxygen gas with the help of sunlight. A photoelectrochemical cell device consists of three main components, one of which is the photoanode. One of the materials that can be used as a photoanode is ZnO which has good electrical properties and is non-toxic. Nanorods-structured ZnO has the advantage of being able to increase light absorption due to its high surface area. However, the resulting performance is still quite low. So it is necessary to make modifications to the photoanode, one of which is by adding aluminium material to ZnO NRs, which has the potential to increase the conductivity of PEC in the production of H2 and O2 in H2O. To overcome the loss of samples during testing, the thin film will be coated with conductive polymers such as polyaniline (PANi), which has high conductivity, can increase photoactive ability, and has good corrosion resistance. In this study, the performance of ZnO NRs/PANi against AZO NRs/PANi will be studied by adding aluminium. The ZnO nanorods were synthesized by Hydrothermal method, Aluminium was deposited on ZnO NRs by DC Magnetron Sputtering method, and PANi was synthesized by polymerization method. From the XRD characterization results, it can be concluded that the addition of aluminium to ZnO NRs/PANi causes an increase in crystallinity and peak shift. SEM characterization shows that the addition of Al to ZnO NRs/PANi causes the porosity value to increase. In addition, UV-Vis characterization showed that the addition of Al material to the ZnO NRs/PANi thin film resulted in a wider range of absorbance of the light spectrum. Then, Cyclic Voltammetry test shows that the addition of aluminium increases the efficiency of the photoelectrochemical.

Abstract: This study aims to determine the problem solving abilities of high school students in solving physics problem topic working and energy. A total of 64 respondents solved physics problem about work and energy which consisted of four questions. The students' answers were evaluated using a rubric consisting of five indicators, namely useful description (UD), physics approach (PA), specific application of physics (SPA), mathematical procedures (MP), and logical progression (LP). The data analysis technique used qualitative descriptive. The results of the analysis show that the score of students' problem solving abilities is in a sufficient category, with the dominant score on indicators UD, PA and SPA. Students get poor score criteria on MP and LP indicators. In this case, students experience some difficulties, among others, students' mistakes in applying physics concepts in mathematical equations, students' mistakes in using equations that are not relevant to the problems presented and students' mistakes in using calculations that do not focus on the problem presented. Abstrak: Penelitian ini bertujuan untuk mengetahui kemampuan pemecahan masalah siswa SMA dalam memecahkan persoalan usaha dan energi. Sejumlah 64 responden mengerjakan soal usaha dan energi yang terdiri atas empat soal uraian. Hasil jawaban siswa dikoreksi dengan menggunakan rubrik yang terdiri atas lima indikator, yaitu usefull description (UD), physics approach (PA), spesific application of physics (SPA), mathematical procedures (MP), dan logical progression (LP). Teknik analisis data menggunakan deskriptif kualitatif. Hasil analisis menunjukkan bahwa skor kemampuan pemecahan masalah siswa berada dalam kategori cukup, dengan dominan skor pada indikator UD, PA dan SPA. Siswa mengalami kriteria kurang baik pada indikator MP dan LP. Dalam hal ini, siswa mengalami beberapa kesulitan, antara lain, kesalahan dalam mengaplikasikan konsep dalam persamaan matematis, menggunakan persamaan yang tidak relevan dengan permasalahan yang dipaparkan menggunakan perhitungan yang tidak fokus pada problem yang disajikan.

Abstract: This study aims to explore the understanding of students' concepts based on the experience of authentic phenomenom-based learning in static fluid material. The method in this study using a mix method approach with embedded experimental model research design. The data were obtained based on the isomorphic multiple choice test and interview support. Through data analysis, the results of the calculation of N-Gain values were obtained which showed there was an increase in students' understanding of concepts in the medium category and the effect size in the low category. Qualitatively, after experiencing authentic learning based on the phenomenon of understanding concepts students experience changes that lead to understanding the correct concepts in each isomorphic. Abstrak: Penelitian ini bertujuan untuk mengeksplorasi pemahaman konsep siswa berdasarkan pengalaman authentic learning berbasis fenomena pada materi fluida statis. Metode dalam penelitian ini menggunakan pendekatan mix method dengan desain penelitian embedded experimental model. Data diperoleh berdasarkan tes pilihan ganda berbentuk isomorfik dan dukungan wawancara. Melalui analisis data, diperoleh hasil perhitungan nilai N-Gain yang menunjukkan terdapat peningkatan pemahaman konsep siswa pada kategori sedang serta effect size pada kategori rendah. Secara kualitatif, setelah mengalami authentic learning berbasis fenomena pemahaman konsep, siswa mengalami perubahan menuju pemahaman konsep yang benar pada setiap isomorfik.

The quantum Diesel of a single fermion in 1D box system has been explored. The Fermion particle meets the Dirac's relativistic Hamiltonian with a chosen mass worth zero. This Relativistic Diesel engine research aims to obtain Diesel engine efficiency that utilizes massless fermion particles as a working substance. This study implements a modified analogy model of the classical analogue model to quantum with the implementation of the first law of thermodynamics for quantum systems so that quantum thermodynamic processes can be defined explicitly. The exploratory results of a single quantum fermion Diesel engine of a single massless system are efficiency formulation that is suitable for the efficiency of a classic Diesel engine, but its heat capacity ratio is unique, that is 2. Based on the value of heat capacity ratio, the efficiency is higher than the classical.

The second Maxwell’s relativistic equations of a rapidaly rotating neutron star, based on ZAMO framework (Zero Angular Momentum Observers) has been formulated. The formulations obtained were epresented by differential equations in the radial, polar, and azimuthal components. The ZAMO basis is implemented because the neutron star reviewed as a rotating star. The second Maxwell’s equation is important to use as one of the fundamental equations to formulate relativistic magnetic fields dynamics of the neutron stars that rotate rapidly.

Abstract: The purpose of this study is to determine the increase of mastery concept in static fluid in inquiry learning with theoretical empirical reviews. The research method uses descriptive analysis. The research subjects consisted of 31 students of SMAN 9 Malang. The measurement instrument is a concept of mastery test questions in the form of a multiple choice of 15 items. The calculation of the question reliability is 0.588 with quite high criteria. The results showed that there was an increase in mastery of the concept of static fluid. The results of the N-gain calculation show that 58% of students are in the upper medium category. This finding indicates that IDAET learning can improve mastery of the concept of static fluid. Abstrak: Tujuan penelitian ini adalah untuk mengetahui peningkatan penguasaan konsep fluida statis dalam pembelajaran inquiry-discovery dengan tinjauan empiris teoritis. Metode penelitian menggunakan analisis deskriptif. Subjek penelitian terdiri atas 31 siswa SMAN 9 Malang. Instrumen pengukuran berupa soal tes penguasaan konsep dalam bentuk pilihan ganda sebanyak 15 butir. Perhitungan reliabilitas soal sebesar 0,588 dengan kriteria cukup tinggi. Hasil penelitian menunjukkan bahwa terjadi peningkatan penguasaan konsep fluida statis. Hasil perhitungan N-gain diperoleh bahwa 58% siswa berada pada kategori medium atas. Temuan ini mengindikasikan bahwa pembelajaran IDAET dapat meningkatkan penguasaan konsep fluida statis

Abstract: The trend of 21st century education is learning based on scientific literacy. Scientific literacy is a key for improving science education in many countries in the world. This article aims to give a profile of the scientific literacy of senior high school students of class XII in the year 2019 in optic subject. This research was conducted with Survey methods. The data is done by providing scientific literacy problem in the form of essays. The subjects of research is the students of class XII at two SMAN Kerinci Regency. Results of this research is scientific literacy of students still low. So that Indonesia can afford prices in the era of the 21st century education, thope that this research can help in determining the solution for improve the ability of students ' scientific literacy. Abstrak: Tren pendidikan abad-21 adalah pembelajaran yang berpatokan pada Literasi Saintifik yang dijadikan sebagai kunci utama dalam meningkatkan pendidikan sains di banyak Negara di dunia. Artikel ini bertujuan untuk memberikan gambaran tentang kemampuan Literasi Saintifik siswa SMA kelas XII pada tahun 2019 terhadap materi Optik. Penelitian ini dilakukan dengan metode survei. Teknik pengambilan data dilakukan dengan memberikan soal literasi saintifik yang berbentuk esai. Subjek penelitian adalah siswa-siswa kelas XII di dua SMAN yang ada di kabupaten Kerinci. Hasil penelitian menunjukkan bahwa literasi saintifik siswa masih rendah. Agar Indonesia mampu bersaing di era pendidikan abad-21, diharapkan penelitian ini dapat memberikan solusi dalam meningkatkan kemampuan literasi saintifik siswa.

Abstract: This study aims to determine the effect of authentic learning based on inquiry for STEM educaton on mastery of students' concepts in work and energy material. Research was conducted on 1 class. The results of this study were seen from the values before being treated using authentic learning based on inquiry for STEM education after being treated using the same learning. The sample of this study was 32 students in class X at SMA Katolik St. Familia Wae Nakeng. The instrument used is a matter of number 5 essay. Data is analyzed qualitatively and quantitatively (N-Gain, effect size). The results show that authentic learning based on inquiry for STEM education affects the mastery of students' concepts, especially in work and energy materials. Abstrak: Penelitian ini bertujuan untuk mengetahui menguji pembelajaran authentic berbasis inquiry for STEM education terhadap penguasaan konsep peserta didik pada materi usaha dan energi. Penelitian dilakukan terhadap satu kelas. Hasil penelitian ini dilihat dari rata-rata nilai sebelum diberi perlakuan menggunakan pembelajaran authentic berbasis inquiry for STEM education dengan rata-rata nilai setelah diberi perlakuan dengan menggunakan pembelajaran yang sama. Sampel penelitian ini berjumlah 32 peserta didik kelas X. Instrumen yang digunakan adalah soal esai lima nomor. Data dianalisis secara kualitatif dan kuantitatif (N-gain, effect size). Hasil ini menunjukkan bahwa pembelajaran authentic berbasis inquiry for STEM education nmemengaruhi penguasaan konsep peserta didik terutama pada materi usaha dan energi.

Abstract: This research examines the increase of students’ ability in working with graph. This research is conducted by involving 58 students in class X SMA Negeri 5 Malang as the subjects. Students are given kinematics learning by making models of various representations including graphics. The ability of students are assessed using multiple choice questions in graphic format. The improvement of students’ ability is observed from the average score pretest and posttest. The analysis shows that there is a significant increase (p = 0.00) with the results of the N-Gain calculation of 0.25 including the medium category. Students are able to change the understanding of graph after learning even though the WYSIWYG effect is still very influential on the way students interpretation graph. Abstrak: Penelitian ini mengkaji peningkatan kemampuan siswa bekerja dengan grafik. Penelitian dilakukan dengan subjek 58 siswa kelas X SMA N 5 Malang. Siswa diberikan pembelajaran kinematika dengan membuat model berbagai representasi termasuk grafik. Kemampuan siswa diukur menggunakan soal-soal multiple choice dalam format grafik. Peningkatan kemampuan siswa ditinjau dari skor rata-rata pretest dan posttest. Analisis menunjukkan ada peningkatan signifikan (p=0,000) dengan hasil perhitungan N-Gain sebesar 0,25 termasuk kategori sedang. Siswa mampu mengubah pemahaman tentang grafik setelah pembelajaran meskipun efek WYSIWYG masih sangat berpengaruh pada cara siswa menginterpretasikan grafik.

Abstract: This research was aimed to describe problem solving skill in Experiential Learning based on the phenomenon, particularly about heat and temperatur. This study was conducted using mix method approach with embedded experimental model research design. The data were collected through pretest and posttest using test and interview. The result of N-Gain Score calculation showed that there are increase in student’s skill on solving problem about temperature and calorie is in moderate category, and the result of d-cohen effect size is in moderate category. At the same time the result of qualitative calculation on student solving skill showed there are 9,4% students in low category, 53,1% student in medium category, and 37,5% student are in high category after experiencing phenomenon based Experimental Learning. Student’s skill in problem solving has to be practiced more intensively using real-life problem in daily life. Abstrak: Penelitian ini bertujuan untuk mendeskripsikan kemampuan pemecahan masalah siswa dalam pembelajaran Experiential Learning berbasis fenomena terutama pada suhu dan kalor. Penelitian ini menggunakan pendekatan mix method dengan desain penelitian embedded experimental model. Data dikumpulkan melalui pretest dan posttest menggunakan tes dan wawancara. Hasil perhitungan N-Gain score menunjukkan adanya peningkatan kemampuan siswa dalam memecahkan suhu dan kalor dalam kategori sedang dan hasil perhitungan d-cohen effect size dalam kategori sedang. Sementara itu, hasil perhitungan kualitatif kemampuan pemecahan masalah siswa melalui crosstabulation menunjukkan sebanyak 9,4% siswa berada pada kategori rendah, 53,1% siswa pada kategori sedang, dan 37,5% siswa pada kategori tinggi setelah mengalami Experiential Learning berbasis fenomena. Kemampuan pemecahan masalah siswa perlu dilatih lebih intensif menggunakan masalah nyata dalam kehidupan sehari-hari.

Abstract: This research was aimed to analyze the mastery of the concept of pressure on interactive demonstration learning model with formative feedback. The study involved 45 students of class VIII SMP Negeri 2 Rembang. The learning process is designed using the interactive learning demonstration stages in which it integrates with formative feedback. Tests form two-tiers as a measure of mastery of student concepts given before and after learning. The test results were analyzed qualitatively and quantitatively. The result of the analysis shows that the learning has an influence on the mastery of student concept with very strong category (very strong). The result of the improvement of students' master comprehension score before and after learning is in the medium category. Students experience an increased level of mastery of the concept from low to high on cognitive indicators of inhibiting (C1), and an increase in concept mastery level from low to moderate on understanding indicators (C2). Overall score indicator mastery of the concept of pressure. In the cognitive indicators of understanding (C3) and analysis (C4) has increased in the low category. Abstrak: Penelitian ini bertujuan untuk menganalisis penguasaan konsep tekanan pada model pembelajaran interactive demonstration disertai formative feedback. Penelitian ini melibatkan 45 siswa kelas VIII SMP Negeri 2 Rembang. Proses pembelajaran dirancang menggunakan tahapan-tahapan pembelajaran interactive demonstration yang didalamnya terintegrasikan dengan formative feedback. Tes bentuk two-tiers sebagai alat ukur penguasaan konsep siswa yang diberikan sebelum dan sesudah pembelajaran. Hasil tes dianalisis secara kualitatif dan kuantitatif. Hasil analisis menunjukkan bahwa pembelajaran tersebut memiliki pengaruh terhadap penguasaan konsep siswa dengan kategori sangat kuat (very strong). Hasil peningkatan skor penguasaan konsep siswa sebelum dan setelah pembelajaran berada pada kategori sedang. Siswa mengalami peningkatan level penguasaan konsep dari rendah menuju tinggi pada indikator kognitif mengingat (C1), dan mengalami peningkatan level penguasaan konsep dari rendah menuju sedang pada indikator memahami (C2). Secara keseluruhan, skor indikator penguasaan konsep tekanan. Pada indikator kognitif memahami (C3) dan analisis (C4) mengalami peningkatan yang masih dalam kategori rendah.

Abstract: This study aims to find out the effect of conceptual scaffolding on Problem Based Learning toward problem solving skills. This research uses nonequivalent control group design with 32 students experimental class and 30 students control class. The test used consisted of a pretest of 13 multiple choice questions with a reliability value of 0.827 and a posttest of 10 essay questions with a reliability value of 0.615. The research hypothesis was tested using ANCOVA and indicate that conceptual scaffolding on PBL given effect to problem solving skills of 67,1% and experimental class average higher than control class. This indicate that there’s effect of conceptual scaffolding on PBL toward problem solving skills. So it’s recommended that conceptual scaffolding on PBL be applied to other physics concepts. Abstrak: Penelitian ini bertujuan untuk mengetahui pengaruh scaffolding konseptual dalam Problem Based Learning terhadap kemampuan pemecahan masalah. Penelitian ini menggunakan nonequivalent control group design dengan sampel sebanyak 32 siswa kelas eksperimen dan 30 siswa kelas kontrol. Tes yang digunakan terdiri dari pretest berupa 13 soal pilihan ganda dengan nilai reliabilitas sebesar 0,827 dan posttest berupa 10 soal esai dengan nilai reliabilitas sebesar 0,615. Hipotesis penelitian diuji menggunakan ANCOVA dan menunjukkan bahwa scaffolding konseptual dalam Problem Based Learning memengaruhi kemampuan pemecahan masalah sebesar 67,1% dan nilai rerata kelas eksperimen lebih tinggi daripada kelas kontrol. Ini menunjukkan adanya pengaruh scaffolding konseptual dalam problem based learning terhadap kemampuan pemecahan masalah. Jadi, disarankan agar scaffolding konseptual dalam problem based learning diterapkan pada konsep fisika lainnya.

Problem solving ability is one of competency that must to be achieved by vocational students. This study aimed to describe the problem solving ability of students to the concept of impulse, momentum, and impulse momentum theorem. The study was conducted to 28 students of class XI Light Vehicle Engineering in one of SMK in Blitar in the academic year 2016/2017. The data description of student’s problems solving ability obtained through tests and interviews. Analysis data was performed by analyzing the test results per item answers to questions. The results showed that the students' problem-solving ability is still less than optimal, namely on the indicator determines the strategy, applying strategies and evaluate solutions. Kemampuan pemecahan masalah menjadi salah satu kompetensi yang harus dicapai oleh siswa SMK. Penelitian ini bertujuan untuk mendeskripsikan kemampuan pemecahan masalah siswa pada konsep impuls, momentum, dan teorema impuls momentum. Penelitian dilakukan kepada 28 siswa Kelas XI Teknik Kendaraan Ringan di salah satu SMK Negeri di Kabupaten Blitar Tahun Pelajaran 2016/2017. Data kesulitan pemecahan masalah siswa diperoleh melalui tes uraian dan wawancara. Analisis data hasil tes dilakukan dengan menganalisis jawaban per butir soal. Hasil penelitian menunjukkan bahwa kemampuan pemecahan masalah siswa yang masih kurang optimal yaitu pada indikator menentukan strategi, mengaplikasikan strategi, dan mengevaluasi solusi.

This research is a mixed methods study aiming at discovering kinematics material concept mastery on X Graders of Senior High School. The subject of this study consisted of 35 students in SMA Negeri 1 Batu. The instrument of this study was multiple choice test amounted to 20 items comprised of three materials which include rectilinear motion, parabolic motion, and circular motion which are represented by representation format. The results showed that the conceptual mastery of the three materials is confirmed improving in the average category. It indicated that multi-representation learning could improve the conceptual mastery on kinematics material. Penelitian ini merupakan penelitian mixed methods yang bertujuan mengungkap penguasaan konsep materi kinematika pada siswa SMA kelas X. Subjek penelitian terdiri atas 35 siswa di SMA Negeri 1 di Kota Batu. Instrumen tes berupa soal pilihan ganda sebanyak 20 butir yang terdiri atas 3 materi, yaitu gerak lurus, gerak parabola, dan gerak melingkar yang disajikan dalam berbagai format representasi. Hasilnya menunjukkan bahwa penguasaan konsep pada ketiga materi mengalami kenaikan dalam kategori sedang. Hal ini mengindikasikan bahwa pembelajaran multi representasi dapat meningkatkan penguasaan konsep materi kinematika.

Mackerel (Rastrelliger sp) is one of small pelagic fish that contribute animal protein intake for local community, so its quality and safety prior to be considered and maintained as follows. In this study analyzes the quality attribute and food safety of mackerel throughout the distribution chain for domestic consumption in Jakarta Province were investigated, from the fish landing, fish auction, wholesale markets, restaurants, supermarkets, until traditional markets. Field observations were used during the investigation, by taking mackerel samples at each distribution chain and testing at the laboratories. Quality characteristics were done by organoleptic test and formaldehyde content were showed the safety level of each samples. The organoleptic parameters revealed that from 100% of samples were taken from fish landing, wholesale market and restaurant comply with Indonesian National Standart, while at the supermarkets and at traditional markets was 77,42%, and 64,78% respectively. This consequently led to an increase of formaldehyde hazardous materials that exhibit during the distribution chain (4 samples from wholesale markets, 6 samples from supermarkets, and 57 samples from traditional markets). The concentrations of formaldehyde in the positive samples at three location mentioned above from 1.0-5.4 ppm, 2.5-6.6 ppm, and 0.2 - 13.4 ppm respectively. Mackerel collected from local markets had lower level of quality and safety compared to those from other locations. Monitoring of using formaldehyde for fresh fish during distribution and marketing need to be conserned. Keywords: domestic, formaldehyde, organoleptic, Quality, Rastrelliger sp. ABSTRAK Ikan kembung merupakan salah satu jenis ikan pelagis kecil yang banyak diminati oleh masyarakat DKI Jakarta sehingga mutu dan keamanannya menjadi salah satu prioritas penting yang perlu diperhatikan. Penelitian ini bertujuan untuk menganalisis mutu dan keamanan ikan kembung di sepanjang rantai distribusi untuk konsumsi domestik di wilayah Provinsi DKI Jakarta, mulai dari Pangkalan Pendaratan Ikan (PPI), Tempat Pelelangan Ikan (TPI), pasar grosir, restoran, pasar swalayan dan pasar tradisional. Metode penelitian yang digunakan adalah observasi lapang dengan melakukan pengambilan sampel ikan kembung pada setiap rantai distribusi dan pengujian di laboratorium. Karakteristik mutu diuji secara organoleptik dan keamanannya diuji dengan parameter kandungan formalin. Hasil penelitian menunjukkan bahwa persentase sampel yang memenuhi standar organoleptik (minimal 7) pada tahap pembongkaran, pasar grosir dan restoran adalah sebesar 100%, pada pasar swalayan dan pada pasar tradisional berturut-turut sebesar 77,42% dan 64,78%. Ikan kembung yang positif mengandung bahan berbahaya formalin masih ditemukan pada pasar grosir (4 sampel), dengan konsentrasi 2,5 – 6,6 ppm, pada pasar swalayan (6 sampel), dengan konsentrasi 1,0 – 5,4 ppm, dan pada pasar tradisional (57 sampel), dengan konsentrasi 0,2 – 13,4 ppm. Ikan kembung yang diambil dari pasar tradisional memiliki mutu dan keamanan yang lebih rendah dibandingkan dengan lokasi lainnya. Pengendalian terkait penggunaan bahan berbahaya formalin pada ikan segar selama distribusi dan pemasaran terutama pada pasar tradisional perlu ditingkatkan. Kata kunci: domestik, formalin, organoleptik, mutu, Rastrelliger sp.