Perspektif Guru Terhadap Pembelajaran Pelajar Remaja

Kajian ini bertujuan untuk meneroka perspektif guru berkaitan dengan pembelajaran pelajar remaja. Kajian ini menggunakan kaedah temubual yang melibatkan seorang guru yang berpengalaman. Instrumen kajian terdiri daripada protokol temubual dan komputer riba. Hasil kajian mendapati bahawa faktor pelajar, faktor guru, dan faktor persekitaran bilik darjah mempengaruhi pembelajaran pelajar remaja. Di samping itu, hasil kajian turut mendapati sekolah yang menyediakan kemudahan dan prasarana yang kondusif serta memberi pengiktirafan dan penghargaan kepada pelajar dan guru mampu meningkatkan pembelajaran pelajar remaja. Dari segi ciri-ciri pelajar remaja yang cemerlang, dapatan kajian menunjukkan bahawa pelajar remaja yang cemerlang memiliki kemahiran etika dan kerohanian, serta sahsiah yang positif. Selain itu, dapatan kajian juga menunjukkan bahawa guru mengakui keberkesanan penggunaan teknologi dan pembelajaran abad ke-21 dalam meningkatkan pembelajaran pelajar remaja. Hasil kajian turut mendapati bahawa guru perlu berkolaborasi dengan pelajar dan menjadi contoh kepada pelajar bagi mewujudkan persekitaran pembelajaran yang kondusif bagi pelajar remaja. Implikasi terhadap aspek pembelajaran pelajar remaja dibincangkan berdasarkan dapatan yang diperoleh dalam kajian ini. Teachers' Perspectives on Teenage Student Learning Abstract: This study aims to explore teachers' perspectives related to adolescent student learning. This study uses an interview method involving an experienced teacher. The study instruments consisted of interview protocols and laptops. The results of the study found that student factors, teacher factors, and classroom environment factors influence the learning of adolescent students. In addition, the results of the study also found that schools that provide conducive facilities and infrastructure as well as give recognition and appreciation to students and teachers are able to improve the learning of adolescent students. In terms of the characteristics of excellent teenage students, the findings show that excellent teenage students have ethical and spiritual skills, as well as a positive personality. In addition, the findings of the study also show that teachers recognize the effectiveness of the use of technology and 21st century learning in improving the learning of adolescent students. The results also found that teachers need to collaborate with students and be an example to students to create a conducive learning environment for adolescent students. Implications on the learning aspects of adolescent students are discussed based on the findings obtained in this study. Keywords: 21st Century Learning, Learning, Teenage Students

Measurement of Solubility of CO2 in NaCl, CaCl2, MgCl2 and MgCl2 + CaCl2 Brines at Temperatures from 298 to 373 K and Pressures up to 20 MPa Using the Potentiometric Titration Method

Understanding the carbon dioxide (CO2) solubility in formation brines is of great importance to several industrial applications, including CO2 sequestration and some CO2 capture technologies, as well as CO2-based enhanced hydrocarbon recovery methods. Despite years of study, there are few literature data on CO2 solubility for the low salinity range. Thus, in this study, the solubility of CO2 in distilled water and aqueous ionic solutions of NaCl, MgCl2, CaCl2 and MgCl2 + CaCl2 were obtained in a low salinity range (0–15,000 ppm) at temperatures from 298–373 K and pressures up to 20 MPa using an accurate and unconventional method called potentiometric titration. An experimental data set of 553 data points was collected using this method. The results of the experiments demonstrate that increasing pressure increases the solubility of CO2 in various brines, whereas increasing temperature and salinity reduces the solubility. The role of different ions in changing the solubility is elaborated through a detailed discussion on the salting-out effect of different ionic solutions. To verify the experimental results of this research, the solubility points obtained by the potentiometric titration method were compared to some of the well-established experimental and analytical data from the literature and a very good agreement with those was obtained

The effect of nanosilica sizes in the presence of nonionic TX100 surfactant on CO2 foam flooding

The aim of this research is to study the effect of hydrophilic silica nanoparticles, sizes as CO2 foam stabilizer in the presence of nonionic TX100 surfactant. Two nanosilica sizes, 15 and 70 nm, have been examined thoroughly. Physisorption of TX100 on silica nanoparticles (nanosilica) was characterized by adsorption isotherm and surface tension measurement, while CO2 foams stability was quantified based on their foamability, foam stability, particle partitioning in the foams, and bubble sizes. Results show that direct contact of TX100 with nanosilica does altered the wettability of hydrophilic nanosilica surface, enable them to lengthen CO2 foams life at certain surfactant and nanoparticles concentrations. For 15 nm nanosilica, CO2 foam stability shows excellent performance at 0.1 and 0.5 wt% TX100 concentrations. As for 70 nm nanosilica, CO2 foam demonstrates longer lifetime at much lower TX100 concentration, 0.01 wt%. Without the presence of TX100, CO2 foams exhibit undesirable lifetime performances for both nanosilica sizes. Nanosilica partitioning in CO2 foams structures demonstrate consistent relation with contact angle measurement. Estimated bubble sizes shows insignificant effect on CO2 foams life. With the assists of nanosilica and TX100, enhanced oil recovery via CO2 foam injection succeeds in increasing oil production by 13–22% of original oil-in-place (OOIP)

Screening the synergy of sodium dodecylbenzenesulfonate and carboxymethyl cellulose for surfactant-polymer flooding

Carboxymethyl cellulose (CMC) has emerged in oil and gas industries as a superior substitution to the conventional HPAM and xanthan gum (XG) for high viscosity polymer flooding application. In this study, the combined effect of conventional surfactant, sodium dodecylbenzenesulfonate (SDBS) and CMC for potential surfactant-polymer (SP) flooding in enhanced oil recovery (EOR) has been investigated. Thereafter, SDBS – CMC interaction and the functional groups present in CMC were appropriately identified. The presence of various C–O bonds signifies the existence of carboxymethyl group which greatly influence the rheological properties of CMC solution. The behaviour of SDBS–CMC was characterized by their viscosity, shear rate, solubilization, wettability, and surface tension. Tertiary flooding utilizing SDBS-CMC was performed and compared to commercial SDBS-XG SP flooding. The results indicate several SDBS-CMC combinations are favourable for EOR application. Solution viscosity shows direct relationship with CMC concentrations. Consequently, at any given SDBS concentrations, significant increment was observed at 0.3 wt% and above. However, the trend displayed inconclusive relation to SDBS fractions. Majority of the SDBS-CMC combinations generate Winsor III emulsions particularly at CMC of 0.2 and 0.3 wt%, while Type II were observed in few combinations. Increasing CMC concentrations increased the contact angle, while gradual reductions were observed with SDBS concentrations. The gradual reduction in surface tension was highly influenced by the addition of CMC rather than SDBS. A novel combination of 0.3 wt% SDBS and 0.4 wt% CMC possessed an encouraging criterion in term of viscosity, solubilization, and surface tension reduction for EOR application. Flooding experiment from several SDBS-CMC combinations proved to recover additional oil ranging 16.4–20.2% of oil initially in place (OIIP). The trend in incremental oil recovery is similar to that of when utilising SDBS-XG