SUATU TINJAUAN TENTANG JENIS-JENIS DAN PENYEBAB MISKONSEPSI FISIKA

Miskonsepsi adalah kesalahanpemahaman dalam menghubungkan suatu konsep dengan konsep-konsep yang lain, antara  konsep yang baru dengan konsep yang sudah ada dalam pikiran siswa, sehingga terbentuk konsep yang salah dan bertentangan dengan konsepsi para ahli Fisika. Miskonsepsi fisika ada lima macam, yaitu: (a) pemahaman konsep awal (preconceived notions); (b) keyakinan tidak ilmiah (nonscientific beliefs); (c) pemahaman konseptual salah (conceptual misunderstandings); (d) miskonsepsi bahasa daerah (Vernacular misconceptions); dan (e) miskonsepsi berdasarkan fakta (factual misconceptions). Penyebab miskonsepsi fisika ada lima bahagian, yaitu siswa (pengetahuan awal atau prakonsepsi/prior knowledge, pemikiran  asosiatif  siswa, pemikiran  humanistik,  reasoning yang tidak lengkap/salah, intuisi yang salah, tahap perkembangan kognitif siswa, kemampuan siswa, dan minat siswa), guru, bahan ajar atau literatur, konteks  dan metode mengajar

Review on performance of self compacting concrete containing solid waste and bibliometric properties: A review

Self-compacting concrete (SCC) is currently an intriguing product due to its ability to reduce labour work and time. Simultaneously, the growing global population and economy result in increased solid waste accumulation in landfills. In addition to occupying a substantial portion of landfill space, the disposal of solid waste also presents widely recognized health and environmental risks to nearby areas. To address these issues, utilizing solid waste as a substitute for cement has been explored as a potential solution. Various types of solid waste, including glass, ceramic, clay brick, banana leaf ash, palm oil fuel ash (POFA), eggshell, and rice husk ash (RHA) have been studied by researchers as cement replacements in SCC. This review aims to explain the impact of using solid waste as cement replacement in SCC on both its fresh and mechanical properties. The findings of this paper review suggest that replacing 10% of POFA, 20% of RHA, 10–15% of glass, 15% of eggshell, 10% of ceramic, and 5% of clay brick for cement results in improved fresh properties and strength of SCC. The optimum percentage of substitution and its impact on the mechanical properties of SCC is determined by the unique characteristics of the waste material being used. In summary, it is deemed acceptable to utilize solid waste as a substitute for cement in SCC to enhance the fresh properties and address environmental concerns

Review of Various Hydroxyapatite Coating Methods on SS316L Foam for Biomedical Application

Metallic biomaterials such as 316L stainless steel (SS316L) are widely used as an implant to replace the function of damaged bone, especially in hip or knee applications. However, many of them fail during a short period or have complications. The biocompatibility issues are the main factor that caused this failure. Thus, coating the SS316L with bioactive and biocompatible material is one of the promising techniques to enhance the biocompatibility and lifetime of the implant. This paper provides an overview of the SS316L foam coated hydroxyapatite (HA). Various methods of HA coating such as sol-gel, dip coating, electrophoretic deposition, plasma spraying, and pulse laser deposition applied on SS316L foam and their coating characteristics were investigated based on recent literature. SS316L foam coated HA using different coating methods were compiled and their basic properties were reported. Therefore, this paper will benefit future works on SS316L foam coated HA in a biomedical application

Enhancement heat transfer characteristics in the channel with Trapezoidal rib–groove using nanofluids

Numerical study of heat transfer due to turbulent flow of nanofluids through rib–groove channel have been investigated. The continuity, momentum and energy equations are solved by the finite volume method (FVM). Four different rib–groove shapes have been examined. Four different types of nanoparticles, Al2O3, CuO, SiO2, and ZnO with different volumes fractions in the range of 1–4% and different nanoparticle diameter in the range of 25–70 nm, have been also studied. The computations are performed under constant temperature over a range of Reynolds number (Re) 10,000–40,000. Results indicate that the Trapezoidal with increasing height in the flow direction rib–trapezoidal groove has the best heat transfer rate and high Nusselt number. It is also found that the SiO2 – nanofluid has the highest value of Nusselt number in comparison with the other type of nanofluids. The Nusselt number increases as the volume fraction increases and it decreases as the nanoparticle diameter increases. The present study shows that these Trapezoidal rib–groove using nanofluids have the potential to dramatically increase heat transfer characteristics and thus can be good candidates for the development of efficient heat exchanger device

Enhance heat transfer in the channel with V-shaped wavy lower plate using liquid nanofluids

The heat transfer and flow characteristics in corrugated with V-shape lower plate using nanofluids are numerically studied. The computations are performed on uniform heat flux over a range of Reynolds number (Re) 8000–20,000. The governing equations are numerically solved in the domain by a finite volume method (FVM) using the k–ε standard turbulent model. Studies are carried out for different types of nanoparticles Al2O3,CuO, SiO2 and ZnO with different volume fractions in the range of 0–4%. Three different types of base fluid (water, glycerin, ethylene glycol) are also examined. Results indicated that the average Nusselt number for nanofluids is greater than that of the base liquid. The SiO2 nanofluid yields the best heat transfer enhancement among all other type of nanofluids. Heat transfer enhancement increase with increases the volumetric concentration, but it is accompanied by increasing pressure drop values. Moreover, the average Nusselt number increases with an increase in Reynolds number and volume concentration. The SiO2–glycerin nanofluid has the highest Nusselt number compared with other base fluids. The present study shows that these V-shaped wavy channels have advantages by using nanofluids and thus serve as promising candidates for incorporation into efficient heat transfer devices