Profil Literasi Sains Peserta Didik SMK pada Penerapan Pembelajaran Projek Electroplating Berbasis Green Chemistry

Scientific literacy is one of the main keys for education personnel in facing the challenges of the 21st century which continues to experience global changes. Project learning is carried out to increase scientific literacy and achieve sustainable development. This study aims to describe the scientific literacy profile of vocational students in the application of green chemistry-based electroplating learning projects. The principles of green chemistry raised in the electroplating project are the use of safe chemicals, the use of green solvents, and waste prevention. The research method used was a descriptive analysis. The research subjects were 27 students from the Industrial Mechanics Engineering program in the Department of Technology and Engineering at a Vocational School in the city of Cimahi for the 2022-2023 Academic Year, selected using the convenience sampling technique. Data collection techniques were carried out using 20 scientific literacy test instrument questions with four answer choices that have been validated and tested for reliability. Data analysis was carried out by paired t-test on pretest and posttest values using the Microsoft Excel program. The scientific literacy profile of SMK students in the domain of science knowledge is categorized as low with a percentage of 48%, the scientific competence domain is categorized as moderate with a presentation of 66%, and the attitude domain is categorized as moderate with a percentage of 63%

IMPLEMENTASI MODUL PEMBELAJARAN JARAK JAUH SEBAGAI PEDOMAN ORANGTUA DALAM PENDAMPINGAN BELAJAR ANAK

Penelitian ini dilatar belakangi oleh kendala guru dalam memberikan pembelajaran kepada anak usia dini pada masa pandemi Covid-19. Dari kendala tersebut muncul inisiatif guru di TK Aisyiyah 5 untuk membuat modul pembelajaran jarak jauh yang diperuntukan kepada orangtua guna memudahkan dalam pendampingan belajar anak. Penelitian ini bertujuan untuk melihat gambaran pembelajaran jarak jauh di TK Aisyiyah 5 serta mengetahui implementasi modul pembelajaran jarak jauh sebagai pedoman orangtua dalam pendampingan belajar anak. Metode penelitian yang digunakan adalah studi kasus dengan pendekatan kualitatif. Teknik pengumpulan data yang digunakan dalam penelitian ini adalah wawacara, obeservasri serta studi dokumentasi dengan partisipan : Kepala Sekolah, guru dan dua orangtua murid. Penelitian ini menggambarkan bagaimana sekolah melakukan inovasi dalam pelaksanaan pembelajaran jarak jauh. Inovasi yang dilakukan menjadikan pemelajaran memiliki ciri khas dalam perencanaan, pelaksanaan dan penilaian pembelajaran. Penggunaan Metode pembelajaran seperti daring, luring dan home visit dilakukan guna memfasilitasi belajar anak. Modul pembelajaran yang di implementasikan dibuat dengan memperhatikan perkembangan anak serta mengacu kepada kurikulum 2013 PAUD dan mengintegrasikannya dengan kurikulum yang ada di lembaga tersebut. Dalam pembelajaran jarak jauh ini juga dipelukan komunikasi yang baik antara guru dengan orangtua murid agar tujuan pembelajaran dapat tercapai dengan optimal. This research was motivated by the obstacles of teachers in providing learning to early childhood during the Covid-19 pandemic. From these obstacles emerged the initiative of teachers at TK Aisyiyah 5 to create distance learning modules intended for parents to facilitate children's learning assistance. This study aims to see the description of distance learning in TK Aisyiyah 5 and to find out the implementation of distance learning modules as a guide for parents in assisting children's learning. The research method used is a case study with a qualitative approach. Data collection techniques used in this study were interviews, observations and documentation studies with the participants: the principal, teacher and two parents. This study describes how schools innovate in the implementation of distance learning. The innovations carried out make learning unique in planning, implementing and assessing learning. The use of learning methods such as online, offline and home visits is carried out to facilitate children's learning. The implemented learning modules are made by taking into account the development of children and referring to the 2013 PAUD curriculum and integrating it with the existing curriculum at the institution. In distance learning, good communication between teachers and parents is also required so that learning objectives can be achieved optimally

PRESENTASI DIRI VIRTUAL WANITA BERCADAR (STUDI KASUS PADA MICRO INFLUENCER BERCADAR DI INSTAGRAM)

Konsep dan strategi presentasi diri menjadi gaya komunikasi perempuan bercadar yang aktif menggunakan media sosial dan melakukan aktivitas swafoto. Persepsi terhadap cadar yang tertutup bertolak belakang dengan yang dilakukan micro influencer bercadar. Namun ketika micro influencer bercadar menampilkan diri di media sosial, mendatangkan persepsi baru dari kalangan masyarakat. Tujuan dari penelitian ini untuk mengidentifikasi stimulus komunikasi berupa konsep dan strategi micro influencer bercadar dalam mempresentasikan diri di media sosial. Selain itu juga memaparkan motivasi dan peranan yang dilakukan micro influencer bercadar sebagai subjek yang diteliti. Adapun dalam melakukan penelitian, peneliti menggunakan metode kualitatif dengan pendekatan studi kasus. Kemudian dalam pengumpulan data, peneliti melakukan wawancara mendalam (Indepth Interview) secara semi-terstruktur dengan micro influencer bercadar, tepatnya sembilan orang informan yang memilki followers instagram antara 1.000-50.000 followers. Selain itu karakteristik lainnya, informan tersebut aktif menggunakan media sosial selama lima tahun terakhir sejak menggunakan cadar. Temuan penelitian ini menunjukan, bahwa beragam stimulus dilakukan oleh micro influencer bercadar dalam mempresentasikan diri di media sosial. Selain itu, peranan dan motivasi berupa mengekspresikan dan mengaktulisasikan diri menjadi salah satu alasan informan dalam mempresentasikan diri di instagram. Hadirnya micro influencer bercadar bukan hanya mengubah persepsi masyarakat yang sebelumnya menganggap perempuan bercadar sebagai sosok yang kaku, eksklusif dan tertutup. Namun juga menghadirkan persepsi bar

Noticeable Reverse Shift in the Melting Temperatures of Benzene and Carbon Tetrachloride Confined within the Micropores and Mesopores of Hydrophobic Carbons

Carbon aerogels contain both mesopores and micropores. In this study, benzene/CCl4 was adsorbed in the pores of carbon aerogels (both mesopores and micropores) and their phase behaviours were examined using differential scanning calorimetry. The bulk solid benzene melted at 278 K and the melting temperatures of benzene confined inside the mesopores and micropores of carbon aerogels were 258 and 293 K, respectively. Although the melting temperature depression of condensates in mesopores is well known, the observed elevation of the melting temperature for micropores is very limited in the strongly interacted system. Similar melting behaviours were observed for the confined CCl4; depression by 45 K in mesopores and elevation by 48 K in micropores showed about two times the change as compared with that of confined benzene.ArticleADSORPTION SCIENCE & TECHNOLOGY. 31(2-3):145-151 (2013)journal articl

Electronically modified single wall carbon nanohorns with iodine adsorption

Tailoring electronic properties of single wall carbon nanohorn (SWCNH) is expected to develop the application potential in various fields. SWCNH is efficiently modified with iodine molecules by liquid phase adsorption. The adsorption isotherm of iodine on SWCNH was Langmuirian with the saturated adsorption amount of 185 +/- 10 mg g (1) (coverage 0.18), indicating a specific interaction between SWCNH and iodine. The DC electrical conductivity of SWCNH film prepared by dip-coating method increased with the iodine adsorption amount almost by a factor 10.ArticleCHEMICAL PHYSICS LETTERS. 501(4-6):485-490 (2011)journal articl

The effect of oxygenated turpentine oil additive in diesel fuel on the performance and emission characteristics in one-cylinder di engines

A study on the application of oxygenated turpentine oil as a bio-additive in diesel fuel was conducted. The purpose of this research was to investigate the effect of oxygenated turpentine oil additive in diesel fuel on the performance and emission characteristics in diesel engines. Oxygenated turpentine oil is obtained from the oxidation process of turpentine oil. In this experimental study, the influences of oxygenated turpentine oil-diesel blended fuel OT0.2 (0.2% vol oxygenated turpentine oil and 99.8% vol diesel) were compared with pure diesel on engine performance, and emission characteristics were examined in a one-cylinder four-stroke CI engine. The test was performed at two engine loads (25% and 50%) and seven engine speeds (from 1200–2400 rpm with intervals of 200 rpm). The physiochemical characteristics of test fuels were acquired. The engine indicated power, indicated torque, fuel flow rate, and emissions (carbon dioxide, CO2; carbon monoxide, CO; and nitrogen oxide, NOX ) were examined. The results revealed that the engine power shows slight increments of 0.7–1.1%, whereas the engine torque slightly decreased with oxygenated turpentine usage compared to pure diesel in most conditions. Furthermore, a reduction in NOX emission decreased by about 0.3–66% with the addition of oxygenated turpentine in diesel compared to diesel. However, usage of OT0.2 decreased fuel flow rate in most speeds at low load but gave a similar value to diesel at 50% load. CO emissions slightly increased with an average of 1.2% compared to diesel while CO2 emissions increased up to 37.5% than diesel. The high-water content, low cetane number, and low heating value of oxygenated turpentine oil were the reasons for the inverse effect found in the engine performances

Investigation of the effect of flow rate on fluid heat transfer in counter-flow helical heat exchanger using CFD method

Heat exchangers are generally used in the process of heat transfer between two different fluids separated from each other by a solid wall in order to save time and reduce expenses. Fluids behavior change by adding a wire-insert in its path. To investigate heat transfer parameters, we need to simulate the whole system. In this study, heat transfer of counter-flow helical double pipe heat exchanger was modelled by using Computational Fluid Dynamics (CFD) in "Ansys CFX". The cold and hot fluids temperature were in the ranges of 10-20C° and 30-50C° respectively. The Reynolds number of flows were in the range of 4×103 to 42×103 and the process was singlephase. The model was eventually evaluated by experimental data after simulation. The results indicated that the model was able to interpret the experimental results with correlation coefficients of 0.98 and 0.97 for hot and cold streams respectively. Furthermore, the wire-insert installed to the cold flow path caused more fluid turbulence and increased the temperature difference of the cold fluid inlet and outlet proportional to the hot fluid

A Comprehensive Investigation of Low Proportion TiO2-POE Nanolubricant Stability for Residential Air Conditioning System Application

The paper aims to expound on the comprehensive experimental investigation of the stability of TiO2-Polyolester (POE) nanolubricant. A magnetic stirrer was used to disperse TiO2 nanopowder into POE lubricant for 30 min. The six samples were then subjected to various ultrasonication treatments lasting 40-, 60-, 80-, 100-, and 120-min. Stability analysis was performed in three stages: visual observation, Ultra Violet (UV) visible spectrophotometric analysis, and measurement of the absolute zeta potential. The results showed that sample without ultrasonication treatment had substantial agglomeration as compared to other samples. The absorbance ratio of the sample without ultrasonication treatment is 0.33. The absorbance ratio value escalated as the duration of the ultrasonication treatment on the sample increases. After ultrasonication treatment for 40–120 min, the absorbance ratio increased by 34–117%. The samples treated with 120 min of ultrasonication showed the highest level of stability, as evidenced by the high absorbance ratio and zeta potential values of 0.95 and −80.48 mV, respectively. As a result, the findings suggests that TiO2-POE with ultrasonication treatment for 120 min could generate the excellent stability compared to other samples in this experiment

Absorbance Ratio Optimization as a Function of TiO2-POE Nanolubricant Spectrophotometric Wavelength Using the Quadratic Design on One Factor at a Time

Errors in the UV visible spectrophotometry analysis’ selection of spectral peaks can lead to errors in the nanolubricant stability analysis. Despite the fact that the spectral peak results are compared at the same peak, it is critical to identify the correct spectral to avoid errors in the nanolubricant stability analysis results. In this study, one factor at a time (OFAT) based on surface response was adopted to determine the effect of wavelength selection on the absorbance ratio of TiO2-POE nanolubricant. The TiO2-POE sample was prepared using a two-steps approach. The sample was ultrasonicated for 100 min using a homogenizer. UV visible spectrophotometry analysis was performed on day 1 and 15 to determine the absorbance ratio. Sixteen runs were performed using a quadratic design to acquire experimental data were fitted. The ANOVA analysis discovered that the experimental statistics were well suited to the polynomial model, with an R2 value of 0.9970 and a model F-value of 2154.24. The findings suggest that the optimum wavelength is 500 nm with an absorbance value of 0.901239 and a desirability level of 1.0