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Universities' identities and institutional images are showcased on their websites to the rest of the world. Nowadays, many university websites (UW)s have been well-investigated for usability improvement for all users in general. This study aims to review the publications indexed in the Scopus database in 2021 using the search term 'University Websites' and to synthesize the main information being discussed in the manuscripts. Two main reasons why only papers published in 2021 were selected for this study. Firstly, in terms of the number of publications (N = 456) indexed in Scopus from 1996 to 2021, the 2021 publications are the most recent complete year. Secondly, 2021 topped the list of publications along with 2020. For the year 2021, a total of 58 publications were found in the Scopus database as of February 26, 2022. After screening all the papers, only 39 papers were used for this quantitative analysis. The present systematic review presented three major trends. Firstly, the publications on the UWs are expected to be higher in near future aligned with the speed of Industry 4.0 development worldwide. Secondly, there is a total of 24 countries and 1 region (Latin America) found in this review, with Indonesia leading the list with 8 publications. Thirdly, all the papers aimed to identify the obstacles and recommended ways and room for future improvements for all users regarding their UWs. This review paper highlighted the importance of having effective and up-to-date websites from social and economic viewpoints. It can be synthesized here that continual improvements in the knowledge of the effective usability of a UW can sustain a university's reputation and ranking ultimately.

During the past decade, deep eutectic solvents (DESs), emerging as green, versatile and adjustable alternatives to traditional solvents, have attracted intensive interests and immense research in various research fields. Especially DESs show quite a remarkable potential dissolving capability, due to their ability to donate as well as accept protons and electrons. A thorough and deep understanding of the microstructure, interactions and dissolving mechanism within DESs plays a key role in acquiring a task-specific DES. Quantum chemistry (QC) calculations provide structure-property-function relationship based on the molecular description and make up for the limitations of the current experimental techniques, showing promises for DESs screening and design. This paper summarizes the current research involving QC calculations and combined experiments, on investigating the structure, physicochemical properties and dissolving capability of DESs from the macroscopic and microcosmic perspective. This paper highlights and discusses the dissolving mechanism of various compounds in DESs, covering the recent successes in applying QC calculations to select the appropriate DESs as dissolving media. Furthermore, a brief analysis of perspectives and challenges for the future research in this field is presented. It is expected that this paper will inspire the future development of DESs from synthesis design to various designated applications.

This paper presents the thermophysical properties of zinc oxide nanofluid that have been measured for experimental investigation. The main contribution of this study is to define the heat transfer characteristics of nanofluids. The measuring of these properties was carried out within a range of temperatures from 25 °C to 45 °C, volume fraction from 1 to 2 %, and the average nanoparticle diameter size is 25 nm, and the base fluid is water. The thermophysical properties, including viscosity and thermal conductivity, were measured by using Brookfield rotational Viscometer and Thermal Properties Analyzer, respectively. The result indicates that the thermophysical properties of zinc oxide nanofluid increasing with nanoparticle volume fraction increasing, as well as the thermophysical properties of zinc oxide nanofluid affected by the change in temperature.

Preserving and saving energy have never been more important, thus the requirement for more effective and efficient heat exchangers has never been more important. However, in order to pave the way for the proposal of a truly efficient technique, there is a need to understand the shortcomings and strengths of various aspects of heat transfer techniques. This review aims to systematically identify these characteristics two of the most popular passive heat transfer techniques: nanofluids and helically coiled tubes. The review indicated that nanoparticles improve thermal conductivity of base fluid and that the nanoparticle size, as well as the concentrations of the nanoparticles plays a major role in the effectiveness of the nanofluids. Regarding the helically coiled tubes, it was discovered that the use of a coiled tube produces secondary flows, which ultimately improves the heat transfer enhancement. The third part of the review focused on microchannels and microtubes. This is mainly due to the growing need and requirement of smaller and more compact thermal cooling systems. Thus, ultimately the result of the review indicates that a combination of all these three techniques can lead to a compact and minimized heat exchanger that uses the benefits obtained from both nanofluids and helically coiled tubes in order to improve the heat transfer rate of the thermal systems.

Microalgae is one of the most important sources of green hydrocarbons and it is likely to reduce dependence on fossil fuels due to the high percentage fats of microalgae, and also has a rapid growth rate and consumes the carbon dioxide in large quantities. Besides, the cultivation of microalgae does not require arable land. This short review aims to explain the suitability of microalgae as a biofuel source depending on the content of lipids, and catalytic chemical processes to convert the crude oil of microalgae into biofuels by using different types of modified HZSM-5 zeolites. Also, this review sheds light on the different methods to modify HZSM-5 zeolite toward enhancing the selectivity of cracking and deoxygenation processes by using modified HZSM-5 zeolite with rare earth metals.

This paper investigates the catalytic upgrading process in overcoming the scrap tire pyrolysis oil (STPO) complexities using a calcium-based catalyst derived from blood cockle shell (Anadara granosa). The calcined blood cockle (CBC) shells were synthesized by varying the temperature of calcination to 800, 900 and 1000 °C. In order to investigate the physico-chemical properties, the STPO was subjected to test method according to ASTM D975. The final distilled oil obtained from catalytic upgrading underwent gas chromatography with mass spectroscopy (GC–MS) analysis, in order to identify its chemical composition. According to the results, CaO material gives the lowest sulphur content (0.08%), compared to Ca(OH)2 and Na2CO3 catalysts. Among the CBC materials, the highest distilled oil yield is the CBC-1000 catalyst, with a value of 37.7%. The GC–MS analysis of distilled oil obtained from catalytic upgrading using the CBC-1000 catalyst reveals that, predominantly, the hydrocarbon chain is between C8 to C10, which is similar to conventional diesel fuel. The results also infer that there is improvement in STPO in terms of sulphur content (%), yield, and chemical compositions via the catalytic upgrading process. In conclusion, the CBC catalyst derived from blood cockle shell revealed that it has potential in upgrading the STPO to diesel-like fuel.

Hydrogen production is an effective way to replace the primary energy to provide renewable sources as well as preserve the environment. Significant efforts have been developed to increase the effectiveness of hydrogen production through many methods. However, the challenge is still on-going, which exhibits insufficient efficiency and weak selectivity toward hydrogen production. Photocatalysis is one of the best methods to produce hydrogen as well as sustained the environment. Here, modification of TiO2 by metal doping photocatalyst is reviewed. The right conclusions only can be obtained if consistent data is used. So, in this review, the data used are only data generated from a research group, Bunsho Ohtani's research group of Hokkaido University, that used titania photocatalyst in the production of hydrogen. The photocatalytic activity of photocatalysts and their relationship with hydrogen production and the factors that affect hydrogen production are discussed critically using fuzzy graph and fuzzy logic modelling. Modification of TiO2 photocatalyst and its application for the production of hydrogen are studied. The modification is designated as mono-, bi-, and trimetallic metal doping. Moreover, there is no clarification has been done on the factors that affect the photocatalytic activity in hydrogen production. Thus, the mathematical tool, which is the fuzzy logic controller (FLC) is introduced in photocatalysis to provide the future direction of the structure-physical properties-photocatalytic activity relationship of metal-doped TiO2 photocatalyst. Au/TiO2 is used as the photocatalyst model towards the production of hydrogen under UV light irradiation in the form of a fuzzy graph. It was found that the low amount of Au metal doping and high surface area are the dominant factors to obtain high-efficiency hydrogen production for Au/TiO2 photocatalyst.

The aim of this study is numerically to investigate the effects of local thermal non-equilibrium porous media on the melting process of paraffin with the melting temperature 33 °C . The geometry consists of a half-cylinder containing paraffin with a uniform constant temperature and an insulating wall. Also, Darcy model and buoyant force due to density changes are considered in this simulation. The effects of the presence of aluminum foam with porosity e = 0.8 , a n d 0.95 and difference temperature Δ T = 5 , 10 , a n d 15 have been studied on the melting fraction of PCM, temperature and streamlines contours and heat flux of cylinder's surface. The observations show that enhancement of porosity 0.8 to 0.9 increases the volume of PCM 11.7%, and reduces time of melting process 30.8% for Δ T = 15 . Moreover, increment of Δ T = 5 t o 15 leads to decrease time of melting process 71.8% when porosity is 0.95.

Carbon self-doped titanium dioxide (C/TiO 2 ) photocatalyst was synthesized by a simple sol-gel method using titanium isopropoxide as both the titanium precursor and carbon source. The effects of calcination temperatures in the range of 300 to 700 °C to the structure and physicochemical properties of the C/TiO 2 were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) coupled with energy dispersive X-ray (EDX), Fourier transform infrared (FTIR) spectroscopy, UV-visible diffuse reflectance (UV-Vis DR) spectroscopy, photoluminescence spectroscopy, N 2 adsorption-desorption and X-ray photoelectron spectroscopy (XPS). XPS results proved the presence of self-doped carbon at the interstitial and substitutional lattice of TiO 2 . The C/TiO 2 calcined at 300 and 400 °C (C/TiO 2 -300 and C/TiO 2 -400, respectively) showed mesoporous characteristic and large surface area of about 100 m 2 g -1 . The C/TiO 2 photocatalysts were then tested in the photo-oxidation of styrene under visible light irradiation with aqueous hydrogen peroxide as the oxidizing agent. The C/TiO 2 photocatalysts were successfully activated under the irradiation of visible light, where C/TiO 2 -300 and C/TiO 2 -400 showed the highest total concentration of products (benzaldehyde and styrene oxide) at 1.1 mmol and 1.0 mmol, respectively. For video presentation, kindly please visit this link

A heterogenous ternary Ni and Ag co-modified g-C3N4 nanocomposite is designed and fabricated using a photoreduction approach for photo-catalytic hydrogen production from methanol-water mixture. Ternary nanocomposite consisting of Ni–Ag co-deposited onto g-C3N4 was successfully fabricated and uniformly distributed, therefore, exhibited strong visible-light absorption and efficient charge carrier separation due to synergistic effect throughout the ternary composite. The nanocomposite with varying amounts of nickel and silver, play an important role to maximize the photoactivity with the optimized 3Ni–1Ag/CN sample delivering H2 of 2137.5 μmolg−1h−1, which is 16.13, 1.42 and 1.52 folds greater than using CN, 3Ni/CN and 3Ag/CN, respectively. This proves that semiconductor composition ratio is important in achieving a successful p-n junction and efficient charge separation and transfer in the ternary composite. The performance of optimized Ni–Ag/CN was further enhanced using photo-reduction method. The highest H2 yield of 5740 μmolg−1 is achieved over the photo-reduced Ni–Ag/CN-R nanocomposite which is 1.25 folds higher than non-photo-reduced composite. This improvement can be accredited to the formation of good p-n junction between the semiconductors in the ternary composite and due to the formation of photo-reduced Ag which acts as electron sinks which leads to improved charge separation. Furthermore, increasing catalyst loading increases the H2 production rate and methanol-water mixture gave the highest H2 production rate. The findings of this study would be beneficial for future hydrogen generation and implementation within newer sustainable systems.

The micro-reactor device was fabricated from Teflon and tested as a tool for biodiesel synthesis process from micro algae using Dodecylbenzenesulfonic acid catalyst. The variables influenceing on the biodiesel yield were optimized. The maximum yield of biodiesel of 99% was obtained at the reaction conditions of (temperature: 373.15 K, residence time: 20 min, methanol/oil ratio: 20, co-solvent amount: 30 wt% and catalyst amount: 11wt%). The influence of water content also investigated and recommended to be less than 0.5 wt %. The acid value also reduced to a value of less than 0.5 % at the optimum reaction condition. DBSA was found highly active catalyst for the esterification and transesterification reaction in the micro – reactor device. Biodiesel was produced in microreactor device at a small residence time (20 min) compared to the very long time consumed by the conventional batch process. Isopropanol was used as a co-solvent in the process and showed highly active in the biodiesel production.

Photocatalytic CO2 reduction by H2O and/or H2 reductant to selective fuels over Cu-promoted In2O3/TiO2 photocatalyst has been investigated. The samples, prepared via a simple and direct sol-gel method, were characterized by XRD, SEM, TEM, XPS, N2 adsorption-desorption, UV–vis diffuse reflectance, Raman and PL spectroscopy. Cu and In loaded into TiO2, oxidized as Cu2+ and In3+, promoted efficient separation of photo-generated electron/hole pairs (e−/h+). The results indicate that the reduction rate of CO2 by H2O to CH4 approached to 181 μmol g−1 h−1 using 0.5% Cu-3% In2O3/TiO2 catalyst, a 1.53 fold higher than the production rate over the 3% In2O3/TiO2 and 5 times the amount produced over the pure TiO2. In addition, Cu was found to promote efficient production of CH3OH and yield rate reached to 68 μmol g−1 h−1 over 1% Cu-3% In2O3/TiO2 catalyst. This improvement was attributed to charge transfer property and suppressed recombination rate by Cu-metal. More importantly, H2 reductant was less favorable for CH4 production, yet a significant amount of CH4 and CH3OH were obtained using a mixture of H2O/H2 reductant. Therefore, Cu-loaded In2O3/TiO2 catalyst has shown to be capable for methanol production, whereas product selectivity was greatly depending on the amount of Cu-loading and the type of reductant. A photocatalytic reaction mechanism was proposed to understand the experimental results over the Cu-loaded In2O3/TiO2 catalyst.

Three types of helical microtube coil namely circle, oval and elliptical are introduced and evaluated both experimentally and numerically. Al2O3-water, ZnO-water at three volume fractions ( ϕ ) of 1.0%, 1.5% and 2% are considered as working fluid as well as the base fluid (water). Different values of pitch are tested with constant pitch/diameter ratio of 1 for all geometries. The numerical simulations are presented the flow structures of helical microtubes in terms of velocity, isotherms, and vorticity contours. Compared to straight coil, the findings show that helical microtube curvature swirls are an important phenomenon to increase heat transfer. In addition, it shows that the heat transfer and friction loss increase as volume fractions of nanofluids and Reynolds number increase. The experiments have also uncovered that the use of helical microtube augment the heat transfer ratio considerably and greatest enhancement ratio was realized by employing circle form with ϕ = 2% of alumina nanofluid. Over ranges of considered flow, alumina nanofluid was better than ZnO-water nanofluid and the best thermal performance of 3.1 was recorded with using it at ϕ = 2% at Reynolds number of 1800. Besides, new empirical correlations were proposed and reported based on experimental data.

This work introduces a numerical study of the convective heat transfer of helical micro coils tube heat exchanger coil. It tested for both circle and elliptical geometry with 18 mm pitch and diameter of copper pipes. It is very difficult and time-consuming if these analyses could be carried out experimentally. Water is used as a working fluid by using 80 C for hot water and 25 C for cold water. The Reynolds number selected in the range of 200 to 1800 for hot water, while specified 5000 for cold water. ANSYS-FLUENT 18.0 has been used to investigate the heat transfer behavior. In computational fluid dynamics (CFD), the partial differential equations was represented by using the finite volume method (FVM) in the form of algebraic equations and the Navier-Stokes equations were solved by using a numerical procedure which is the Semi Implicit Method for Pressure-Linked Equations (SIMPLE) algorithm. The elementary results observed a proportionality relationship between the heat transfer and the Reynolds number raised values. Also, the circular configuration present maximum heat transfer performance and the maximum values are 5.6, 3.42 for Thermal performance factor and Nuselte number respectively at Reynolds number 1800.

A single-phase of perovskite-type oxide material can be prepared at a processing temperature relatively lower than 1000 °C through a sol-gel method. However, it is affected by the nature of chemical additives employed during the synthesis process. In the present work, sol-gel derived lanthanum strontium cobaltite, La0.6Sr0.4CoO3-δ (LSC64) material is prepared using various non-ionic surfactants namely polyoxyethylene (10) oleyl ether (Brij-97), polyoxyethylene octyl phenyl ether (Triton-X-100) and polyoxyethylene (20) sorbitan monooleate (Tween-80). The prepared powders of the LSC material is subsequently subjected to the thermal decomposition, phase formation and microstructure analysis by a thermal gravimetric analyzer, an X-ray diffractometer and a scanning electron microscope (SEM), respectively. The as-synthesized powders are calcined at different temperatures based on the thermal gravimetric analysis results. X-ray diffractometer results reveal that all of the calcined powders consist of more than 90 % perovskite phase of LSC64 and other secondary phases such as cobalt oxide, lanthanum oxide and strontium carbonate. The Brij-97-based and Tween-80-based calcined powders have morphology of typical clump-like network structure, while the Triton-X-100-based calcined powder has morphology of flake-like network structure.

Au-NPs-embedded Z-scheme WO3/TiO2 hetero-junction for boosting photocatalytic H2 evolution from glycerol-water mixture under visible light has been investigated. The composite samples, synthesized by a sol-gel assisted photo-deposition method, gave higher visible light absorption through Surface Plasmon Resonance (SPR), larger BET surface area and hindered recombination of charge carrier. Highest H2 evolution rate of 17200 ppm h−1 gcat−1 was obtained over 0.5%Au-loaded WO3/TiO2 which was 4.46 and 5.89 folds higher than WO3/TiO2 and TiO2, respectively. This divulges that constructing WO3/TiO2 Z-scheme hetero-junction adjusted redox potential, while decorating plasmonic Au-NPs enables faster charges separation with higher visible-light absorption through SPR, resulting in superior H2 production. In addition, both water splitting and photocatalytic glycerol reforming contributed towards excellent H2 formation. The apparent quantum yield of 28.3% (λ ~ 420 nm) was attained and catalyst prevailed photo-stability for H2 evolution in cyclic runs. This study provides new insight about constructing plasmonic assisted Z-scheme assembly for solar fuels production.

This article provides Numerical simulation on forced convective heat transfer performance of Nanofluid flowing through copper helical microtube of inner diameter of 1.5 mm with different pitch using ANSYS-FLUENT 18.0. The simulation was performed for water, CuO/water, Al2O3/water Nanofluid with 1-2% volume concentration and different pitch of microtube (10, 14 and 18 mm) for turbulent flow regime of Reynolds number varied 5000 to 20000 and governing equations of mass, momentum and heat transfer were solved simultaneously, using the k-e two equations turbulence model. Based on the obtained results, regardless of the concentrations used, the nanofluids exhibited a higher transfer rate than water. This is mainly attributed to the nanoparticles that are in the used nanofluids. The friction factor and the heat transfer rate were enhanced considerably due to the shape and size of the tube, which in this case is a helical microtube. Moreover, the maximum heat transfer performance has been conducted by Al2O3/water Nanofluid with 2% volume concentration and microtube pitch of 18 mm.

This research studied the characteristics of nanofluids in a concentric tube heat exchanger. The objectives of this research are to prepare the stable nanofluids with addition of surfactant and to investigate the stability, properties, and heat transfer of nanofluids in concentric tube heat exchanger. Aluminium oxide (Al2O3) was added to base fluid deionized water (DW) with addition of polyvinylpyrrolidone (PVP) as surfactant by two-step method. First, the best stability ratio of nanofluids to surfactant PVP was determined by preparing several samples of 0.50 wt% nanofluids with addition of different weight fraction of surfactant. Thus, each sample has different ratio and being observed for one week by visual observation. Then, nanofluids samples (0.25, 0.50, 0.75 and 1.00 wt%) were prepared based on the best stability ratio. The properties and heat transfer of nanofluids were analyzed at different concentration of nanofluids and at different temperatures (room temperature, 40 °C, 50 °C, 60 °C and 70 °C)....

The Agent-Based Intelligent Tutoring System is developed to fulfill the needs for effective tutorial tool that can be adapted to the needs and characteristics of software engineering students. Specifically, it is expected to help learners understand function point metrics, a subtopic in software engineering metrics syllabus. This intelligent tutor allows student to perform function point analysis in an environment that provides visualization, immediate feedback, interactive and guided help. The intelligent component for this system comes from the ability to adapt course module and needs for individual user. Thus adaptation is being done by modeling the expert's and student's knowledge. The essential part of an interactive and intelligent system is the interface that allows knowledge to be added to the system. Intelligent agent is embedded into the tutoring system, allowing the agent to use the added knowledge to answer questions and solve problem in function point metrics domain. The aim of the system is to enhance the learners' knowledge to a better level of subject matter understanding and enhance the delivery of domain knowledge from the subject matter expert. This paper introduces the architecture for agent-based Intelligent Tutoring System which uses Function Point Metrics as the domain knowledge. Generally the development of this system follows the agent oriented software engineering life cycle which comprise of specification, design implementation and verification. In particular, the design phase is discussed in this paper. The architecture introduces three components, the Learner Module, the Domain Module and the Tutoring Module. The ITS includes three agents, User Interface Style Agent, Log Agent, Practice Agent. The system is expected to enhance the learners learning level and enhance the teaching for the subject matter expert.

This paper reports on MDM of a combination ofhelical-phased modes comprising ring modes and HG modes.44Gbps data transmission is achieved by a wavelength divisionmultiplexing (WDM) - MDM system of two center-launchedhelical-phased ring modes and two 3μm radially offset HG modeon wavelengths 1550.12nm and 1551.72nm for a 1500m-longmultimode fiber. The power coupling coefficients, degeneratemode group delays and bit error rates are analyzed for differentHG modes and radial offsets.