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The present research attempts to develop a hybrid coolant by mixing alumina nanoparticles with cellulose nanocrystal (CNC) into ethylene glycol-water (60:40) and investigate the viability of formulated hybrid nanocoolant (CNC-Al2O3-EG-Water) towards enhancing the machining behavior. The two-step method has been adapted to develop the hybrid nanocoolant at various volume concentrations (0.1, 0.5, and 0.9%). Results indicated a significant enhancement in thermal properties and tribological behaviour of the developed hybrid coolant. The thermal conductivity improved by 20-25% compared to the metal working fluid (MWF) with thermal conductivity of 0.55 W/m℃. Besides, a reduction in wear and friction coefficient was observed with the escalation in the nanoparticle concentration. The machining performance of the developed hybrid coolant was evaluated using Minimum Quantity Lubrication (MQL) in the turning of mild steel. A regression model was developed to assess the deviations in the tool flank wear and surface roughness in terms of feed, cutting speed, depth of the cut, and nanoparticle concentration using Response Surface Methodology (RSM). The mathematical modeling shows that cutting speed has the most significant impact on surface roughness and tool wear, followed by feed rate. The depth of cut does not affect surface roughness or tool wear. Surface roughness achieved 24% reduction, 39% enhancement in tool length of cut, and 33.33% improvement in tool life span. From this, the surface roughness was primarily affected by spindle cutting speed, feed rate, and then cutting depth while utilising either conventional water or composite nanofluid as a coolant. The developed hybrid coolant manifestly improved the machining behaviour.

Fused deposition modeling (FDM) is a practical 3D printing technology to print thermoplastic and composite materials. The FDM 3D printing process has gained substantial attention due to its capability to produce complex and accurate components. Recently, the wood particles-based filament in 3D printing has become a subject of interest, which is due to their prominent advantages, such as thermal resistivity, corrosion resistivity, biodegradable characteristics, and being environmentally friendly. Therefore, this research study aims to investigate the mechanical properties and statistical prediction model development for coconut wood–polylactic acid (PLA). The experimental investigation was carried out according to the ASTM standards (tensile—ASTM D638 Type 1, compression—ASTM D695, and bending—ASTM D790) at different infill densities (25, 50, and 70%) and five different infill patterns. The obtained results proved that concentric infill pattern accompanied by 75% infill percentage achieved the most outstanding tensile and bending behavior. For compression testing, grid infill pattern accompanied by 75% infill percentage exhibits maximum compression properties. In overall, the octagram spiral infill pattern shows the weakest properties among all the infill patterns. The experimental results were further analyzed using response surface methodology to identify the effectiveness of studied parameters on mechanical properties and to derive a mathematical model. The derived mathematical models related to studied mechanical properties have been proposed to predict the desired mechanical properties with respect to the variation of infill patterns and percentages.

The present paper focuses on the crystal structure characteristics of electrodeposited Cobalt (Co) nanowires synthesized via a template-assisted electrodeposition (TAE) process. Detailed XRD analysis investigated the crystal orientation and crystal size to understand the effect of synthesis current density and temperature. Though polycrystallinity is one of the main disadvantages of the TAE process, studies indicate the presence of single-crystalline Co nanowire regions, confirmed by HRTEM and selected area electron diffraction. TEM image of Cobalt nanowire with SAED pattern morphology and XRD spectra of electrodeposited cobalt nanowires at different current densities and temperatures.

Dispersion of conducting polymer-based nanocomposite in Phase Change Materials (PCMs) tends to enhance the thermophysical properties. Present work aims to synthesize and disperse conducting polyaniline@cobalt nanocomposite within the Paraffin matrix to improve the thermo-physical property. Polyaniline based nanocomposites with 1.0 and 2.0 wt% cobalt (PC1 and PC2) were sonicated with paraffin at different weight ratio of 0.1%, 0.5%, 1%, and 5% and characterization of nanocomposite dispersed phase change material was performed. Thermo-physical properties were analysed by using thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC). Thermal conductivity of nanocomposite enhanced paraffin increased with increase in weight% of both PC1 and PC2 till 1% of its weight in paraffin and decreased for 5% of PC1 and PC2 concentration with paraffin. TGA readings observed drop in initial decomposition temperature of PPC1-5% (Paraffin with PC1 in 5% concentration) and PPC2-5% (Paraffin with PC2 in 5% concentration) by an amount of 08% and 12.4% respectively compared with base PCM Paraffin wax. DSC results of PPC1-0.1% and PPC2-0.5% showed 182.04 J/g and 170.86 J/g latent heat of fusion as compared to Paraffin wax. The samples were tested for 200 thermal cycles and the chemical stability and thermal property were compared with the fresh samples.

Processing conditions during the deposition process affect the nanowire properties significantly in template-assisted electrodeposition, an effective method for growing freestanding and well-dispersed nanowires. In this work, we study the effect of current density and temperature on electrodeposited cobalt (Co) nanowire synthesized via a template-assisted process. Scanning electron microscopy was used to study the morphology of formed cobalt nanowires with EDS analysis, confirming Co as the main element. In addition, the length and growth characteristics of the formed nanowires are analyzed and discussed. SEM morphology and deposition length characteristics of electrodeposited cobalt nanowires at different current densities and temperatures.

This study attempts to provide a statistical evaluation of the effect of Cu wt.% and infill pattern on the FDM-based 3D printed parts' impact properties. The developed model is based on the acquired experimental data accompanied by response surface methodology (RSM) analysis. The confidence level for RSM is set to 95% (? = 0.05), where P-value lower than 0.05 shows a significant effect by the parameter. Besides determining significant parameters, this analysis also provides modeling of impact properties and optimizes the desired mechanical performance parameter. ANOVA analysis includes data of standard deviation (S), coefficient of determination (R2), adjusted and predicted (R2). Infill pattern and Cu wt.% show a significant effect on both factors, including energy absorbed and impact strength. The model created for the energy absorbed and impact strength has an error of 7.23 % and 6.60 %. The maximum energy absorbed and impact strength obtained through optimization is 2.5180 J and 35.3657 kJ/m2, respectively, through the combination of two main factors, including Concentric infill pattern with 25 wt.% Cu. The mathematical models of the impact properties were also developed using RSM, focusing on varying copper composition and infill patterns, which can be used to predict desired impact properties.

3D printing is an emerging technology to construct complex geometry by adapting layer-by-layer addition technique from a 3-dimensional CAD model. Mass customization, freedom of design, and wastage minimization are the main advantages of Additive Manufacturing (AM) based 3D printing. 3D printing is currently used in many sectors worldwide, such as automotive, aerospace, agriculture, medical, electronics, and other household products. However, the usage of the AM technique is limited in large production sectors due to the limitation of the materials and properties of the produced parts. In this review, the different methods of 3D printing, the materials used in different processes, various fields of applications, and the properties of the different approaches are discussed. Also, the effect of process parameters such as layer thickness, nozzle temperature, platform temperature, printing speed, extruding rate, and layer height in 3d printing was reviewed. This will be helpful for further development of 3D printed product quality and applications in various sectors.

The energy sector is witnessing a gradual shift towards renewable energy sources in the past few decades. Solar energy is the most widely harnessed one although it exhibits unevenness in distribution. Integrating latent heat storage materials into Photovoltaic systems could function as thermal storage batteries which can regulate the intermittency in solar radiations. The effective heat management of the thermal energy storage system is greatly affected by the poor thermal conductivity of phase change materials. To improve the thermal conductivity of palmitic acid (phase change material), metal oxide nanoparticles (copper oxide having size 30–50 nm) were added in various concentrations ranging 0.1% and 0.5% weight. The thermal conductivity was found to be enhanced by 3.55%, 8.86% respectively. Thermal stability was also improved with nanoparticle addition. Transmittivity decreased by 9.6% with 0.5% addition of nanoparticles. These results suggest that the novel composite could be effectively employed in thermal energy storage applications.

The global increase in energy demand has resulted in the depletion of non-renewable resources and caused environmental degradation. Consequently, emerging renewable technologies are a potential solution to fulfil energy demand and mitigate the effect of global warming. Low-cost solar energy harvesting technologies are most feasible technologies. Various solar cells technologies have been developed with improved overall performance and conversion efficiency. However, due to low cost and a wide range of applications, dye-sensitized solar cells (DSSCs) have been immensely focused on one of the most promising third-generation solar cells. The highest conversion efficiency of DSSC achieved after three decades of research is more than 14%, but the commercialization of this technology is still a challenge. In this review paper, an attempt has been made to present the comparison of different articles published, that gives the in-depth study of recent developments in various types of DSSCs based on architectural assembly and physical appearance. An overview of the limitations and challenges with their possible improvement strategies have also been discussed. This review paper concludes that appropriate selection of electrolytes dramatically affects the performance of DSSC, and quasi-solid-state electrolyte proves to be a better option. Besides, it also concludes that tandem structures are widely agreed with the approach to expand light utilization spectrum for an overall increase in its performance. However, still, the research is required, which could efficiently widen the applications of the DSSCs.

Template-assisted electrochemical deposition is a straight forward approach for the synthesis of 1D nanostructures (e.g., nanowire, nanorod, and nanobelt) with controllable morphology. This approach is suitable for mass production as it works at ambient pressure and temperature with the properties of synthesized 1D nanostructures being influenced by synthesis conditions during the electrochemical deposition process. This work aims to investigate the influence of stabilizing agent concentration and heating temperature towards the physical behavior of Nickel (Ni) nanowires synthesized via a template-assisted electrochemical deposition approach. In this research, the electrolyte bath was prepared in three different concentrations of the stabilizing agent (6 g/L, 40 g/L and 70 g/L), and the deposition bath temperature used was 30°C, 70°C, and 110°C respectively. The elemental composition was determined using Energy Dispersive X-ray (EDX) analysis to investigate the percentage of pure Ni element in the synthesized nanowires. The diameter, surface texture, and growth length of the synthesized Ni nanowires were characterized using Field Emission Scanning Electron Microscope (FESEM). X-ray diffractions (XRD) was used for crystal size and crystal orientation analysis. Additionally, the mechanical properties of Ni nanowires were extracted via molecular dynamic simulation. Growth length of Ni nanowires found to be significantly improved as the heating temperature increased, but it decreased when stabilizer agent concentration is high. The diffraction patterns for all synthesis conditions exhibited the synthesis Ni nanowires are polycrystalline as the crystalline planes with Miller indices of 111, 200, and 220. All the investigated nanowires showed ductile failure behavior, a typical behavior at larger length scales of Ni.

Polyaniline nanotubes (PANI NTs) blended in refined, bleached and deodorized palm olein (RBDL) nanolubricants were prepared via a two-step method. Initially, the synthesized PANI NTs were characterized to investigate the morphology and elemental composition of the obtained PANI NTs. The obtained image from transmission electron microscopy clearly showed the presence of flake-like structure of PANI NTs. The presence of these PANI NTs was further affirmed with energy-dispersive X-ray analysis, which shows the presence of high carbon atoms (the main element for PANI NTs). The formulated surfactant-free nanolubricants were stabilized using ultrasonication with volume concentrations of 0.01, 0.03, 0.05, 0.1, 0.3 and 0.5%. The dispersion behavior of nanolubricants was investigated using visual sedimentation capturing, UV–Vis spectrophotometer and dynamic light scattering (DLS) method. The sedimentation observation of the nanolubricants over the duration of almost 1 month showed there was no sedimentation of the nanoparticles. UV–Vis spectra indicated that all the prepared PANI/RBDL nanolubricants followed Beer–Lambert law. The value of absorbance was found to be slightly decreased, with respect to the duration of time after sample preparation. The dispersion stability analysis supported by DLS method revealed that the amount of particles agglomeration increased after 1 month of preparation. The chemico-physical properties of prepared PANI/RBDL nanolubricants were further investigated by analyzing the chemical bonding using Fourier-transform infrared spectroscopy (FTIR). Additionally, this study intends to investigate the influence of PANI NTs toward the life cycle of base oil via thermogravimetric (TG) analysis. FTIR analysis showed that nanolubricants were chemically stable as there were only physical interactions between PANI additives and RBDL base oil, while the degradation behavior in TG curve demonstrated that the nanolubricants could withstand higher temperature as the volume concentration of nano-additives increased. Rheology and thermal conductivity properties of PANI/RBDL nanolubricants were performed by using rheometer and thermal properties analyzer, respectively. Viscosity measurement revealed that PANI/RBDL nanolubricants exhibited Newtonian behavior. Also, viscosity was found to have been increased with a volume concentration of PANI NTs but decreases with the increase in temperature. From the thermal conductivity measurement, it is proven that the PANI NTs dispersed in the RBDL palm base oil support the thermal properties enhancement. The 0.5% PANI/RBDL nanolubricants had achieved the highest thermal conductivity of 0.4301 W m−1 K −1 at 80 °C with enhancement percentage of 25.76% when compared to conventional base oil at a similar temperature.

Photovoltaic thermal (PVT) systems are increasingly becoming an essential part of the solar application systems integrating the photovoltaic (PV) and solar thermal collectors into a single unit to produce heat and electrical energy from the intermittent solar irradiation. Energy systems are usually analyzed by energy and exergy analyses. Most of these systems are designed considering their energy performances based on the 1st law of thermodynamics. Generally, the energy reduction occurring in systems can be detected using exergy analysis and is a valuable tool for investigating the energy efficiency of energy systems, thereby helping the complicated thermodynamic systems more efficient. The exergoeconomic analysis is a form of economics focused on exergy analysis and is a hybrid of exergy and cost analysis to enhance the output of PVT systems. This allows designers to determine strategies to enhance the system efficiency from its cost perspective. Herein, a detailed literature review on energy, exergy and exergoeconomics (3E) analysis and their applications in air-based, water-based and bi-fluid PVT systems with and without integrated phase change materials (PCMs) is executed. It was found that water-based PVT systems with PCMs (PVT-PCM) are more feasible as the energy and exergy efficiencies are enhanced and their energy payback time reduced as compared to other conventional systems. The energy and exergy efficiencies of the water-, air- and bi-fluid-based PVT systems integrated with PCMs were found to be higher than the systems without PCM integration. PCM integration with a water-based PVT system can lead to the storage of thermal energy and also enhance the overall exergetic efficiency of the system up to 25%. The exergy efficiencies of PVT systems were found to be between 3–14%, and generally less than their energy efficiencies. Thus, 3E analysis is found to be a more technical approach to assess the performance of PVT systems and gives a complete overview of the performance of the system.

Nanotechnology has emerged to be an essential aspect of science and technology. The growth of this field has been enormous specifically in the development of nanomaterials. Till date, numerous nanomaterials have been developed and designed to suit various applications from mechanical to biomedical. Among the developed nanomaterial, alumina (Al) has been subject of interest due to its notable chemical and physical properties. Specifically, in thermal properties, Al has been shown to have superior thermal conductivity, convective heat transfer coefficient and heat transfer coefficient properties. As such, Al has been utilized in different forms in various fields of applications and verified for its importance, significance and efficiency. Though it had shown outstanding results in the field engineering and sciences, their effect towards the environment and human health is yet to be explored extensively. The present paper aims to review the significance of Al nanoparticle addition in mono- and hybrid nanofluids. Also, this paper intends to provide the reader with an overview of the works that have been carried out using Al nanoparticles and their findings.

This study investigates the performance of thin-film cadmium telluride (CdTe) building integrated photovoltaic (BIPV) arrays (facade and roof) under tropical weather conditions in Malaysia. This in...

Nano-lubricant is a new kind of engineering lubricant composed of nanometer-sized particle dispersed in a base lubricant. Recently, nanoparticles have been explored as lubricant additives for improving the stability and lubricity properties of a technological fluid. Cellulose nanocrystals (CNC), a unique and natural material extracted from native cellulose, has gained much attention in many field application due to its remarkable physical properties, special surface chemistry, and excellent biological properties, making them attractive as a green lubricant additive. The purpose of this study is to investigate the characterization of the CNC nanoparticles and to evaluate the influence of CNC nanoparticles on the lubricating properties added to the base oil. In this study, CNC nanoparticles were prepared and suspended in five different volume concentrations in the engine oil (0.1, 0.3, 0.5, 0.7 and 0.9%). The kinematic viscosity and viscosity index of the resulting nano lubricant was determined while varying both the nanoparticle volume fraction and the temperature. The size, morphology, and structure of CNC nanoparticles were characterized using Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray (EDX) and X-ray diffractions (XRD). The dispersion analysis of CNC nanoparticles in lubricating oil using UV spectrometer confirms that CNC nanoparticles possess good stability and solubility in the lubricant and improve the lubricating properties of the engine oil. The overall results of this experiment reveal that the addition of CNC nanoparticle with base 0il SAE40 lubricant shows the highest value of VI and most suitable concentration for improving properties of the base oil.

Since a decade ago, investigation on nanofluids has grown significantly owing to its enhanced thermal properties compared to conventional heat transfer fluids. This engineered nanofluid has been widely used in the thermal engineering system to improve their energy consumption by improving the thermal efficiency of the system. The addition of nano-size particles as additives dispersed in the base fluids proved to significantly either improve or diminish the behaviour of the base fluids. The behaviour of the base fluid highly depends on the properties of the additives material, such as morphology, size, and volume fraction. Among the variety of nanoparticles studied, the conducting polymers have been subject of high interest due to its high environmental stability, good electrical conductivity, antimicrobial, anti-corrosion property and significantly cheap compared to other nanoparticles. As such, the main objective of the present review is to provide an overview of the work performed on thermal properties performance of conducting polymers based nanofluids.

This paper evaluates and discusses the building-integrated photovoltaic (BIPV) system energy losses during the energy conversion process from sunlight into electricity. An approach based on partial performance ratio (P-PR) and cumulative performance ratio (C-PR) is used. The P-PR and C-PR are evaluated considering eight stages possible in the energy conversion stage in photovoltaic (PV) energy systems. A large-scale BIPV system is proposed by retrofitting the existing university buildings is investigated, and the observed results depict the impact of energy losses over the performance ratio decline. Results showed that the P-PR of the BIPV as per eight energy conversion stages varies between 85.6 and 100%. The C-PR varies between 74 and 100%, recording an overall system performance ratio (PR) of 74% under tropical weather conditions. The energy losses are varied within the range of −0.27 to −14.8% (−4 to −223 kWh/kWp) in different energy conversion stages. The total energy losses in the BIPV system account for 26% (−419 kWh/kWp). Based on the observations, reasons for various losses and their mitigation strategies are explored. Thus, we believe this study could provide useful information on the feasibility of considering retrofitting the university buildings with the BIPV modules.

This article offers a trend of inventions and implementations of photocatalysis process, desalination technologies and solar disinfection techniques adapted particularly for treatment of industrial and domestic wastewater. Photocatalysis treatment of wastewater using solar energy is a promising renewable solution to reduce stresses on global water crisis. Rendering to the United Nation Environment Programme, 1/3 of world population live in water-stressed countries, while by 2025 about 2/3 of world population will face water scarcity. Major pollutants exhibited from numerous sources are critically discussed with focus on potential environmental impacts & hazards. Treatment of wastewater by photocatalysis technique, solar thermal electrochemical process, solar desalination of brackish water and solar advanced oxidation process have been presented and systematically analysed with challenges. Both heterogenous and homogenous photocatalysis techniques employed for wastewater treatment are critically reviewed. For treating domestic wastewater, solar desalination technologies adopted for purifying brackish water into potable water is presented along with key challenges and remedies. Advanced oxidation process using solar energy for degradation of organic pollutant is an important technique to be reviewed due to their effectiveness in wastewater treatment process. Present article focused on three key issues i.e. major pollutants, wastewater treatment techniques and environmental benefits of using solar power for removal of pollutants. The review also provides close ideas on further research needs and major concerns. Drawbacks associated with conventional wastewater treatment options and direct solar energy-based wastewater treatment with energy storage systems to make it convenient during day and night both listed. Although, energy storage systems increase the overall cost of the wastewater treatment plant it also increases the overall efficiency of the system on environmental cost. Cost-efficient wastewater treatment methods using solar power would significantly ensure effective water source utilization, thereby contributing towards sustainable development goals.

Fused deposition modeling (FDM) has been the preferred technology in 3D printing due to its ability to build functional complex geometry parts. The lack of the printing parameter information and prediction model that directly reflects towards 3D printed part's mechanical properties has been a barrier for the FDM 3D printer users to appraise the product's strength as a whole. In the present work, 27 tensile specimens with different parameter combinations were printed using a low-cost FDM 3D printer according to the ASTM standard to evaluate their tensile properties. Statistical analysis was performed using MINITAB to validate the experimental data and model development. The investigational outcomes reveal that ultimate tensile strength was primarily affected by infill density, whereby it increases with increasing infill density. Elastic modulus, fracture strain, and toughness were mainly affected by infill density and layer thickness. The ideal printing parameter for optimal tensile behavior was identified to be 0.3 mm layer height, 40° raster angle, and 80% infill density from the 9th combination. The tensile values obtained for the optimal printing parameter were 28.45150 MPa for ultimate tensile strength, 0.08012 mm/mm for fracture strain, 828.06000 MPa for elastic modulus, 20.19923 MPa for yield strength, and 1.72182 J/m3 for toughness. The statistical analysis further affirmed the optimum printing has a minimal deviation from the experimental response. Finally, a mathematical model is proposed for the tensile properties prediction.

Due to the increasing demand in industrial application, nanofluids have attracted the considerable attention of researchers in recent decades. The addition of nanocellulose (CNC) with water (W) and ethylene glycol (EG) to a coolant for a radiator application exhibits beneficial properties to improve the efficiency of the radiator. The focus of the present work was to investigate the performance of mono or hybrid metal oxide such as Al2O3 and TiO2 with or without plant base-extracted CNC with varying concentrations as a better heat transfer nanofluid in comparison to distilled water as a radiator coolant. The CNC is dispersed in the base fluid of EG and W with a 60:40 ratio. The highest absorption peak was noticed at 0.9% volume concentration of TiO2, Al2O3, CNC, Al2O3/TiO2, and Al2O3/CNC nanofluids which indicates a better stability of the nanofluids&rsquo, suspension. Better thermal conductivity improvement was observed for the Al2O3 nanofluids in all mono nanofluids followed by the CNC and TiO2 nanofluids, respectively. The thermal conductivity of the Al2O3/CNC hybrid nanofluids with 0.9% volume concentration was found to be superior than that of the Al2O3/TiO2 hybrid nanofluids. Al2O3/CNC hybrid nanofluid dominates over other mono and hybrid nanofluids in terms of viscosity at all volume concentrations. CNC nanofluids (all volume concentrations) exhibited the highest specific heat capacity than other mono nanofluids. Additionally, in both hybrid nanofluids, Al2O3/CNC showed the lowest specific heat capacity. The optimized volume concentration from the statistical analytical tool was found to be 0.5%. The experimental results show that the heat transfer coefficient, convective heat transfer, Reynolds number and the Nusselt number have a proportional relationship with the volumetric flow rate. Hybrid nanofluids exhibit better thermal conductivity than mono nanofluids. For instance, a better thermal conductivity improvement was shown by the mono Al2O3 nanofluids than the CNC and TiO2 nanofluids. On the other hand, superior thermal conductivity was observed for the Al2O3/CNC hybrid nanofluids compared to the other mono and hybrid ones (Al2O3/TiO2).

Fused deposition modeling (FDM) technology works with specialized 3D printers and production-grade thermoplastics to build robust, durable, and dimensionally stable parts with the best accuracy and repeatability of any other available 3D printing technology. FDM is one of the highly used additive manufacturing technology due to its ability to manufacture very complex geometries. However, the critical problems with this technology have been to balance the ability to produce esthetically appealing products with functionality and properties at the lowest cost possible. In this study, three major process parameters such as layer height, raster angle, and infill density have been considered to study their effects on mechanical properties of acrylonitrile butadiene styrene (ABS) as this material is widely used industrial thermoplastic in FDM technology. The test results show a clear demonstration of the considered factors over the mechanical variables measured. Response surface methodology is used for the validation of the experimental data and the future prediction of the test results. It was found that the optimum parameters for 3D printing using ABS are 80% infill percentage, 0.5 mm layer thickness, and 65° raster angle. The achieved experimental ultimate tensile strength, elastic modulus, yield strength, fracture strain, and toughness (energy absorption) are 31.57 MPa, 774.50 MPa, 19.95 MPa, 0.094 mm/mm, and 2.28 Jm−3, respectively. Mathematical equation has been developed using surface response methodology which can be used to predict the ABS tensile properties numerically and also to predict the optimum parameter for ultimate properties.

In this paper, cellulose nanocrystal (CNC) – ethylene glycol (EG) + Water (W) based nanofluid was developed and assessed for their thermophysical properties and the usefulness towards machining performances. The nanofluid was prepared by adopting two-step preparation method and at volume concentration of 0.1%, 0.3%, 0.5%, 0.7%, 0.9%, 1.1%, 1.3% and 1.5%. The nanofluid with 1.3% and 1.5% concentration showed to have superior the conductivity properties, around 0.559 W/m·K at 70 °C. However, the 0.5% concentration has the highest stability with 0.52 W/m·K at 70 °C. The 0.5% nanofluid concentration was then selected for the machining performance evaluation. The machining performance was evaluated by using a lathe machining operation to determine the heat transfer and tool life properties. The cutting variables such as cutting speed, depth of cut and feed rate are varied to understand the effect of developed nanofluid on the machining bahaviour. Findings revealed that the tool failure on machining using MWF is flank wear, chipping and abrasion and fractured at the maximum cutting distance of 500 mm. However, machining using CNC-EG+W nanofluid revealed the tool failure to be flank wear, adhesion and build- up-edge (BUE) and fractured at the maximum cutting distance of 772 mm.

In past decades, nanofluid science has been widely investigated for thermal related activities. In thermal transport applications, thermal conductivity and dynamic viscosity are closely related to cooling system performance enhancement. The genuine anomaly behind thermal conductivity and dynamic viscosity enhancement in nanofluid is still undiscoverable. In this paper, comprehensive study on principle factor behind thermophysical property enhancement focusing on thermal conductivity and dynamic viscosity is conducted. Thus, a detailed review of existing experimental results for thermal conductivity and dynamic viscosity enhancement are compiled and discussed in this manuscript. Analytical tool approach such as fishbone diagram and summary tables are used to highlight principle factor for thermal conductivity and dynamic viscosity enhancement. The principal factor which influences the thermal conductivity is shape of the particle, nanofluid preparation, interfacial layer, Brownian motion, particle clustering and aggregation. Meanwhile, the principal factor influencing dynamic viscosity is the physical behavior of the particle, nanofluid preparation, particle clustering and aggregation. The optimum nanofluid should have high thermal conductivity and minimum viscosity. High thermal conductivity is mandatory for maximum heat absorption in thermal transport applications. Meanwhile, minimum viscosity ensures less pressure drop which reduces the power consumption and increases the overall efficiency of the system.

LEDs, of late, have received attention as the next generation lighting system for enhanced luminous efficiency and higher lifespan. However, the thermal management of the LEDs is the crucial parameter to be countered for global acceptance as a revolutionary illumination source. This paper reports the experimental investigation of natural convective heat transfer of high power LED COBs using MWCNT and MWCNT-CuO nanofluids mixed with de-ionized water. The study uses MWCNT based nanofluids as a route to enhance the heat transfer of high power LEDs by the passive cooling technique. This study presents an innovative cooling device integrated with numerous fluid pockets, called the HSFP, to achieve the enhanced thermal performance of heat sinks for applications in high intensity LED lights. Nanofluids of various concentrations were formulated and their heat transfer performance evaluated using a series of experiments and compared with liquid cooling and a conventional heat sink. The experimental finding reveals 20–30% lowered thermal resistance using the new HSFP (nanofluids). Thus, the HSFP found to effectively dissipates the heat in high-power LED COBs using nanofluids as the cooling medium compared to the conventional heat sink.

High performance tubular carbon membrane (TCM’s) for CO 2 separation were prepared by controlling the carbonization heating rates in range of 1-7 o C/min carbonized at 800 o C under Argon environment. A single permeation apparatus was used to determine the gas permeation properties of the membrane at room temperature. Fine turning of the carbonization condition was necessary to obtain the desired permeation properties. The preparation of PI/NCC-based TCM at low heating rate caused the gas permeance for the examined gas N 2 and CO 2 decreased whereas the selectivity of CO 2 /N 2 increased. It was also identified that the gas permeation properties of the resultant TCM and its structure was highly affected by the heating rate. The best carbonization heating rate was found at 3 o C/min for the fabrication of TCM derived via polymer blending of PI/NCC for CO 2 /N 2 separation.

The emphasis of this paper is to evaluate the thermophysical properties of crystalline nanocellulose (CNC)-based nanofluid and the optimized machining parameters (cutting speed, feed rate and depth of cut) for machining using CNC-based nanofluid. Cutting tool temperature and formed chip temperature during machining are determined with CNC-based coolant and metal working fluid. Minimum quantity lubrication technique is used to minimize the usage of the coolant. Nanocellulose coolant with a concentration of 0.5% shows better thermal conductivity and viscosity. Total heat produced at the cutting tool and the temperature generated at the chip during machining shows significant improvement using CNC-based nanofluid. Statistical analysis reveals that feed rate and depth of cut contribute around 27.48% and 22.66% toward cutting temperature. Meanwhile, none of the parameters significantly affects the heat transfer. The multi-objective optimization reveals that the optimum parameter for machining using CNC-based nanocoolant is: cutting speed = 120, feed rate = 0.05 and depth of cut = 1.78 which produces heat transfer of 379.44 J and cutting temperature of 104.41 °C.

This paper presents the investigation of Al2O3/PAG nanolubricant performance for a compact vehicle mobile air conditioning (MAC) system. The Al2O3/PAG nanolubricant in this study is prepared by using two-step preparation method and stabilized using 4-Step UV–Vis Spectral Absorbency Analysis. An enhancement in the coefficient of performance (COP), reduction in compressor work, and enhancement in the cooling capacity of MAC employing Al2O3/PAG nanolubricant are recorded up to 31%, 26% and 32%, respectively, for 0.010% volume concentration. The current MAC performance is compared with MAC employing SiO2/PAG nanolubricant from previous study. The comparison shows that the Al2O3/PAG nanolubricant has better performance in term of cooling capacity, compressor work, and COP at an average of 6%, 8%, and 33%, respectively. Therefore, the finding from this study suggests Al2O3/PAG nanolubricant with a volume concentration of 0.010% as an optimum and best performance nanolubricant for MAC systems.

Environmental, economic and political pressures have driven the interest towards the search of sustainable feedstock for biofuel production. At present, macroalgae (green, brown and red marine seaweed) is getting growing consideration as an alternative resource for sustainable biomass to produce biofuels, biochemical and food. The unique chemical composition and wide variation in the availability create various opportunities and also challenges for bio-based energy production. Recently, numerous studies have taken place in the exploitation of seaweed as carbon sources for the bioethanol production. Thus, this paper attempts to highlight the characteristics, processing techniques and potential applications of the seaweed. The present review also focuses on recent innovative approaches for the sustainable production of bioenergy from seaweed.

Solar energy in built environments became more popular in the recent years emerging as building integrated photovoltaics (90° facade and 0° roof BIPV). However, in most cases, residential buildings...

Recently, with the fast advancement of nanoscience and nanotechnology, metallic nanowires (MNW) have received additional attention among researchers. Metallic nanowires have many unique behaviors that are not seen in bulk materials which material properties and functionalities of the bulk tend to differ when its dimensions are reduced down to nano-sized. The development of novel devices such as molecular electronics, supercapacitors, touch sensors, and transparent electronics is due to their versatile properties such as high electrical and thermal conductivity, optical transparency and chemical inertness. Metallic nanowires are also attractive because they can be readily fabricated with various techniques. This paper will provide an overview and summarize current research and advances regarding metallic nanowire technologies, their applications, the process involved in the synthesis of the metallic nanowire, and the techniques used to study and characterize metallic nanowires. Further discussions are presented on the modeling of the metallic nanowire to understand and extract their mechanical behavior.

Green cooling system usage in machining is getting favors to minimize the environmental effect such as pollutions. Around 20% of the machining cost is about coolant usage in flooded cooling technique. Even though coolant has a reasonably low cost, their handling and disposing cost are very high and also, threatening toxic contents, disposal of used coolant is a big problem as it can lead to hazardous effect to the machining operates as well as to the environment. As an alternative, a cooling technique known as minimum quantity lubrication (MQL) was introduced in the machining operation. For MQL technique, the coolant should exhibit superior properties which are effective in machining operation when compared with the conventional machining coolant which is metal working fluid (MWF). Owing to the technology advancements by nanotechnology in nanomaterial, the nanofluid is a promising coolant that can replace the conventional machining coolant. In the present work, ethylene glycol/nanocellulose-based nanofluid is evaluated in terms of its thermo-physical properties and its effectiveness in machining performances which is temperature distribution in cutting tool and compare its effectiveness with MWF. Its effectiveness is tested in turning machining operation of SUS 304 stainless steel using cemented tungsten-cobalt (WC-Co)-coated carbide cutting insert. The turning operation by using ethylene glycol/nanocellulose-based nanofluid coolant with 0.5 vol% which exhibit a superior thermal conductivity of 0.449 W/m K than 0.267 W/m K thermal conductivity of MWF at 30 °C. The recorded lower amount of heat transfer to the cutting tool is 863 J compared with 1130 J when using MWF. On the other hand, the maximum temperature reading recorded at chip formed by using MWF is 225 °C whereas by using nanofluid is 154 °C which promises lower temperature distribution to chip formed during the machining operation. Also, the functionality of nanofluid as a thermal transport during machining is proven via chip formation observation analysis and scanning electron microscope (SEM) with energy-dispersive X-ray (EDX) spectrum analysis.