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Computer programming and IoT are the key skills required in Industrial Revolution 4.0 (IR4.0). The industry demand is very high and therefore related students in this field should grasp adequate knowledge and skill in college or university prior to employment. However, learning technology related subject without applying it to an actual hardware can pose difficulty to relate the theoretical knowledge to problems in real application. It is proven that learning through hands-on activities is more effective and promotes deeper understanding of the subject matter (He et al. in Integrating Internet of Things (IoT) into STEM undergraduate education: Case study of a modern technology infused courseware for embedded system course. Erie, PA, USA, pp 1–9 (2016)). Thus, to fulfill the learning requirement, an integrated learning tool that combines learning of computer programming and IoT control for an industrial liquid filling system model is developed and tested. The integrated learning tool uses NodeMCU, Blynk app and smartphone to enable the IoT application. The system set-up is pre-designed for semi-automation liquid filling process to enhance hands-on learning experience but can be easily programmed for full automation. Overall, it is a user and cost friendly learning tool that can be developed by academic staff to aid learning of IoT and computer programming in related education levels and fields

Computer programming and IoT are the key skills required in Industrial Revolution 4.0 (IR4.0). The industry demand is very high and therefore related students in this field should grasp adequate knowledge and skill in college or university prior to employment. However, learning technology related subject without applying it to an actual hardware can pose difficulty to relate the theoretical knowledge to problems in real application. It is proven that learning through hands-on activities is more effective and promotes deeper understanding of the subject matter (He et al. in Integrating Internet of Things (IoT) into STEM undergraduate education: Case study of a modern technology infused courseware for embedded system course. Erie, PA, USA, pp 1–9 (2016)). Thus, to fulfill the learning requirement, an integrated learning tool that combines learning of computer programming and IoT control for an industrial liquid filling system model is developed and tested. The integrated learning tool uses NodeMCU, Blynk app and smartphone to enable the IoT application. The system set-up is pre-designed for semi-automation liquid filling process to enhance hands-on learning experience but can be easily programmed for full automation. Overall, it is a user and cost friendly learning tool that can be developed by academic staff to aid learning of IoT and computer programming in related education levels and fields.

Computer programming and IoT are the key skills required in Industrial Revolution 4.0 (IR4.0). The industry demand is very high and therefore related students in this field should grasp adequate knowledge and skill in college or university prior to employment. However, learning technology related subject without applying it to an actual hardware can pose difficulty to relate the theoretical knowledge to problems in real application. It is proven that learning through hands-on activities is more effective and promotes deeper understanding of the subject matter (He et al. in Integrating Internet of Things (IoT) into STEM undergraduate education: Case study of a modern technology infused courseware for embedded system course. Erie, PA, USA, pp 1–9 (2016)). Thus, to fulfill the learning requirement, an integrated learning tool that combines learning of computer programming and IoT control for an industrial liquid filling system model is developed and tested. The integrated learning tool uses NodeMCU, Blynk app and smartphone to enable the IoT application. The system set-up is pre-designed for semi-automation liquid filling process to enhance hands-on learning experience but can be easily programmed for full automation. Overall, it is a user and cost friendly learning tool that can be developed by academic staff to aid learning of IoT and computer programming in related education levels and fields

The unique behavior of one-dimensional nanostructure, nanorods in semiconductors has accentuated its utilization in various applications over the other nanostructures in recent decades. Intensive research was conducted and establishes the fact that the larger surface area nanorods demonstrate a lower Auger rate, long carrier lifetime, and linearly polarized emission. Numbers of semiconductor nanorods have been studied progressively in recent years, not to mention the promising advanced material, metal halide perovskites. As the perovskite nanorods have been intensively incorporated in different areas of applications, their recent development is rarely reviewed. In this review, the recent progress of metal perovskite nanorods is addressed by starting with the early appearance of semiconductors nanorods and their progress over the years. Subsequently, the synthesis methods and several factors that dictate the final morphology of the nanocrystals are elucidated. The fascinating applications of the perovskite nanorods in energy devices, photodetectors, and other optoelectronic devices are discussed followed by the challenges to the invention of metal halide perovskite nanorods. Lastly, the conclusion of this review and our outlook on the future progress of this material are presented.

The unique behavior of one-dimensional nanostructure, nanorods in semiconductors has accentuated its utilization in various applications over the other nanostructures in recent decades. Intensive research was conducted and establishes the fact that the larger surface area nanorods demonstrate a lower Auger rate, long carrier lifetime, and linearly polarized emission. Numbers of semiconductor nanorods have been studied progressively in recent years, not to mention the promising advanced material, metal halide perovskites. As the perovskite nanorods have been intensively incorporated in different areas of applications, their recent development is rarely reviewed. In this review, the recent progress of metal perovskite nanorods is addressed by starting with the early appearance of semiconductors nanorods and their progress over the years. Subsequently, the synthesis methods and several factors that dictate the final morphology of the nanocrystals are elucidated. The fascinating applications of the perovskite nanorods in energy devices, photodetectors, and other optoelectronic devices are discussed followed by the challenges to the invention of metal halide perovskite nanorods. Lastly, the conclusion of this review and our outlook on the future progress of this material are presented.

An amperometric nitrite sensor is reported based on a screen-printed carbon electrode (SPCE) modified with copper(II)-benzene-1,4-dicarboxylate (Cu-BDC) frameworks and iron(III) oxide nanoparticles (Fe2O3 NPs). First, copper(I) oxide (Cu2O) nanocubes were synthesized, followed by a solvothermal reaction between Cu2O and H2BDC to form square plate-like Cu-BDC frameworks. Then, Fe2O3 NPs were electrodeposited on Cu-BDC frameworks using a potentiostatic method. The Fe2O3@Cu-BDC nanocomposite benefits from high conductivity and large active surface area, offering excellent electrocatalytic activity for nitrite oxidation. Under optimal amperometric conditions (0.55 V vs. Ag/AgCl), the sensor has a linear range of 1 to 2000 µM with a detection limit of 0.074 µM (S/N = 3) and sensitivity of 220.59 µA mM−1 cm−2. The sensor also provides good selectivity and reproducibility (RSD = 1.91%, n = 5). Furthermore, the sensor exhibits long-term stability, retaining 91.4% of its original current after 4 weeks of storage at room temperature. Finally, assessing nitrite in tap and mineral water samples revealed that the Fe2O3@Cu-BDC/SPCE has a promising prospect in amperometric nitrite detection.

An amperometric nitrite sensor is reported based on a screen-printed carbon electrode (SPCE) modified with copper(II)-benzene-1,4-dicarboxylate (Cu-BDC) frameworks and iron(III) oxide nanoparticles (Fe2O3 NPs). First, copper(I) oxide (Cu2O) nanocubes were synthesized, followed by a solvothermal reaction between Cu2O and H2BDC to form square plate-like Cu-BDC frameworks. Then, Fe2O3 NPs were electrodeposited on Cu-BDC frameworks using a potentiostatic method. The Fe2O3@Cu-BDC nanocomposite benefits from high conductivity and large active surface area, offering excellent electrocatalytic activity for nitrite oxidation. Under optimal amperometric conditions (0.55 V vs. Ag/AgCl), the sensor has a linear range of 1 to 2000 µM with a detection limit of 0.074 µM (S/N = 3) and sensitivity of 220.59 µA mM−1 cm−2. The sensor also provides good selectivity and reproducibility (RSD = 1.91%, n = 5). Furthermore, the sensor exhibits long-term stability, retaining 91.4% of its original current after 4 weeks of storage at room temperature. Finally, assessing nitrite in tap and mineral water samples revealed that the Fe2O3@Cu-BDC/SPCE has a promising prospect in amperometric nitrite detection.

BACKGROUND: The intense interactions between people, animals and environmental systems in urban informal settlements compromise human and environmental health. Inadequate water and sanitation services, compounded by exposure to flooding and climate change risks, expose inhabitants to environmental contamination causing poor health and wellbeing and degrading ecosystems. However, the exact nature and full scope of risks and exposure pathways between human health and the environment in informal settlements are uncertain. Existing models are limited to microbiological linkages related to faecal-oral exposures at the individual level, and do not account for a broader range of human-environmental variables and interactions that affect population health and wellbeing. METHODS: We undertook a 12-month health and environmental assessment in 12 flood-prone informal settlements in Makassar, Indonesia. We obtained caregiver-reported health data, anthropometric measurements, stool and blood samples from children < 5 years, and health and wellbeing data for children 5-14 years and adult respondents. We collected environmental data including temperature, mosquito and rat species abundance, and water and sediment samples. Demographic, built environment and household asset data were also collected. We combined our data with existing literature to generate a novel planetary health model of health and environment in informal settlements. RESULTS: Across the 12 settlements, 593 households and 2764 participants were enrolled. Two-thirds (64·1%) of all houses (26·3-82·7% per settlement) had formal land tenure documentation. Cough, fever and diarrhoea in the week prior to the survey were reported among an average of 34.3%, 26.9% and 9.7% of children aged < 5 years, respectively; although proportions varied over time, prevalence among these youngest children was consistently higher than among children 5-14 years or adult respondents. Among children < 5 years, 44·3% experienced stunting, 4

type:Journal Article, A highly flexible electrochemical supercapacitor electrode was developed with a novel metal oxide-reinforced nanofiber electrode by utilizing a solution-based electrospinning technique. The facile fabrication steps involved the introduction of metal precursors into a polymeric solution, which was subjected to an in situ electrospinning process. The electrospun polymeric web with metallic ingredients was then subjected to an oxidative stabilization process that induced the formation of metal oxide nanoparticles within the polymer structure. Finally, the metal oxide nanoparticles incorporated with nanofibers were obtained using a carbonization process, thus converting the polymer backbones into a carbon-rich conductive nanofiber structure. The fabricated nanofibers were decorated and implanted with metal oxide nanoparticles that had a surface-decorated structure morphology due to the solubility of the precursors in the reaction solution. The electrochemical performance of the fabricated metal oxide reinforced with nanofiber electrodes was investigated as an electrochemical system, and the novel morphology significantly improved the specific capacitance compared to a pristine carbon nanofiber membrane. As a result of the uniform dispersion of metal oxide nanoparticles throughout the surface of the nanofibers, the overall capacitive behavior of the membrane was enhanced. Furthermore, a fabricated free-standing flexible device that utilized the optimized nanofiber electrode demonstrated high stability even after it was subjected to various bending operations and curvatures. These promising results showed the potential applications of these lightweight, conductive nanofiber electrodes in flexible and versatile electronic devices.

Herein we report the doping mechanism and impedance study of the Nb-substituted Bi3Ta1-xNbxO7 (0 ≤ x ≤ 0.5) prepared via conventional solid-state method at 900 °C over 24 h. The substitutional solid solution crystallised in a cubic fluorite structure, space group Fm-3m and with lattice parameter, a = b = c, in the range 5.4477 (±0.0037)–5.4654 (±0.0011) Å. An insignificant unit cell expansion was observed with increasing Nb2O5 content and the linear correlation between lattice parameter and composition variable showed that the Vegard's Law was obeyed. Both TGA and DTA analyses confirmed that the Bi3Ta1-xNbxO7 solid solution was thermally stable as neither phase transition nor weight loss was observed within the studied temperature range, ∼28 °C–1000 °C. The electrical conductivities of these samples were found to increase with increasing Nb concentration; the Bi3Ta0.5Nb0.5O7 exhibited the highest conductivity, ∼1.2 × 10−2 S cm−1 at 700 °C with a low activation energy of 1.03 eV.

Herein we report the doping mechanism and impedance study of the Nb-substituted Bi3Ta1-xNbxO7 (0 ≤ x ≤ 0.5) prepared via conventional solid-state method at 900 °C over 24 h. The substitutional solid solution crystallised in a cubic fluorite structure, space group Fm-3m and with lattice parameter, a = b = c, in the range 5.4477 (±0.0037)–5.4654 (±0.0011) Å. An insignificant unit cell expansion was observed with increasing Nb2O5 content and the linear correlation between lattice parameter and composition variable showed that the Vegard's Law was obeyed. Both TGA and DTA analyses confirmed that the Bi3Ta1-xNbxO7 solid solution was thermally stable as neither phase transition nor weight loss was observed within the studied temperature range, ∼28 °C–1000 °C. The electrical conductivities of these samples were found to increase with increasing Nb concentration; the Bi3Ta0.5Nb0.5O7 exhibited the highest conductivity, ∼1.2 × 10−2 S cm−1 at 700 °C with a low activation energy of 1.03 eV.

Graphene oxide has been used widely as a starting precursor for applications that cater to the needs of tunable graphene. However, the hydrophilic characteristic limits their application, especially in a hydrophobic condition. Herein, a novel non-covalent surface modification approach towards graphene oxide was conducted via a UV-induced photo-polymerization technique that involves two major routes; a UV-sensitive initiator embedded via pi-pi interactions on the graphene planar rings, and the polymerization of hydrophobic polymeric chains along the surface. The functionalized graphene oxide successfully achieved the desired hydrophobicity as it displayed the characteristic of being readily dissolved in organic solvent. Upon its addition into a polymeric solution and subjected to an electrospinning process, non-woven random nanofibers embedded with graphene oxide sheets were obtained. The prepared polymeric nanofibers were subjected to two-step thermal treatments that eventually converted the polymeric chains into a carbon-rich conductive structure. A unique morphology was observed upon the addition of the functionalized graphene oxide, whereby the sheets were embedded and intercalated within the carbon nanofibers and formed a continuous structure. This reinforcement effectively enhanced the electrochemical performance of the carbon nanofibers by recording a specific capacitance of up to 140.10. F/g at the current density of 1. A/g, which was approximately three folds more than that of pristine nanofibers. It also retained the capacitance up to 96.2% after 1000 vigorous charge/discharge cycles. This functionalization technique opens up a new pathway in tuning the solubility nature of graphene oxide towards the synthesis of a graphene oxide-reinforced polymeric structure.

The combination of graphene nanoplatelets and carbon nanofibers were successfully fabricated by utilizing a one-step solution based on the electrospinning technique. A distinctive morphology was observed in which the platelets were suspended between the fibrous structure that significantly improved the specific capacitance of the nanofiber to 86.11 F g−1, twice the increment from its original structure. Furthermore, all of the graphene nanoplatelets-reinforced samples recorded an optimal performance of over 90% capacitive retention after 1000 continuous charge/discharge cycles, regardless of the GnP concentration. These findings indirectly reflect the potential of CNF as the electrode material in the fabrication of high performance supercapacitor devices.

The combination of graphene nanoplatelets and carbon nanofibers were successfully fabricated by utilizing a one-step solution based on the electrospinning technique. A distinctive morphology was observed in which the platelets were suspended between the fibrous structure that significantly improved the specific capacitance of the nanofiber to 86.11 F g−1, twice the increment from its original structure. Furthermore, all of the graphene nanoplatelets-reinforced samples recorded an optimal performance of over 90% capacitive retention after 1000 continuous charge/discharge cycles, regardless of the GnP concentration. These findings indirectly reflect the potential of CNF as the electrode material in the fabrication of high performance supercapacitor devices.

Graphene oxide has been used widely as a starting precursor for applications that cater to the needs of tunable graphene. However, the hydrophilic characteristic limits their application, especially in a hydrophobic condition. Herein, a novel non-covalent surface modification approach towards graphene oxide was conducted via a UV-induced photo-polymerization technique that involves two major routes; a UV-sensitive initiator embedded via pi-pi interactions on the graphene planar rings, and the polymerization of hydrophobic polymeric chains along the surface. The functionalized graphene oxide successfully achieved the desired hydrophobicity as it displayed the characteristic of being readily dissolved in organic solvent. Upon its addition into a polymeric solution and subjected to an electrospinning process, non-woven random nanofibers embedded with graphene oxide sheets were obtained. The prepared polymeric nanofibers were subjected to two-step thermal treatments that eventually converted the polymeric chains into a carbon-rich conductive structure. A unique morphology was observed upon the addition of the functionalized graphene oxide, whereby the sheets were embedded and intercalated within the carbon nanofibers and formed a continuous structure. This reinforcement effectively enhanced the electrochemical performance of the carbon nanofibers by recording a specific capacitance of up to 140.10. F/g at the current density of 1. A/g, which was approximately three folds more than that of pristine nanofibers. It also retained the capacitance up to 96.2% after 1000 vigorous charge/discharge cycles. This functionalization technique opens up a new pathway in tuning the solubility nature of graphene oxide towards the synthesis of a graphene oxide-reinforced polymeric structure.

There are considerable amount of dyes to be discharged in the effluent from dyeing and finishing processes in the textile industry. The discharged dyes are known to be toxic, carcinogenic and mutagenic toward the aquatic system. A low concentration of dyes in the effluent can affect the aesthetic and transparency of water stream. Remaining dyes in the effluent necessitated colour removal along with the stringent restrictions and regulations established. Agricultural waste generally is preferred due to its cost-effective and good performance in adsorption. Pineapple plant stem (PPS) is one of the agricultural residues after shoots transplantation. Utilisation of PPS in dyes removal not only can remediate textile wastewater but also reduce the agricultural waste management problem in Malaysia. In the present study, the performance of pineapple plant stem for cationic (Basic Blue 3, BB3) and anionic (Congo Red, CR) dyes removal has been evaluated in a batch process. The isotherm equilibrium studies indicated that BB3 could be well described by Freundlich model (R² = 0.999) while high correlation values of CR obtained from Langmuir (R² = 0.999) and Temkin (R² = 0.997) models. The maximum sorption capacities for BB3 and CR were found to be 59.52 and 11.92 mg g¯¹, respectively under a favourable sorption process. The dependency of BB3 and CR adsorption on temperature was validated by van’t Hoff equation. The effect of temperature on the BB3 and CR removal by PPS was ascertained by studying the temperature-dependence dyes distribution between bulk solution and adsorbent, and the interaction between dyes and adsorbent. Removal of BB3 and CR by PPS was found to be exothermic. The result suggests that PPS has higher affinity on cationic than anionic dye.

There are considerable amount of dyes to be discharged in the effluent from dyeing and finishing processes in the textile industry. The discharged dyes are known to be toxic, carcinogenic and mutagenic toward the aquatic system. A low concentration of dyes in the effluent can affect the aesthetic and transparency of water stream. Remaining dyes in the effluent necessitated colour removal along with the stringent restrictions and regulations established. Agricultural waste generally is preferred due to its cost-effective and good performance in adsorption. Pineapple plant stem (PPS) is one of the agricultural residues after shoots transplantation. Utilisation of PPS in dyes removal not only can remediate textile wastewater but also reduce the agricultural waste management problem in Malaysia. In the present study, the performance of pineapple plant stem for cationic (Basic Blue 3, BB3) and anionic (Congo Red, CR) dyes removal has been evaluated in a batch process. The isotherm equilibrium studies indicated that BB3 could be well described by Freundlich model (R² = 0.999) while high correlation values of CR obtained from Langmuir (R² = 0.999) and Temkin (R² = 0.997) models. The maximum sorption capacities for BB3 and CR were found to be 59.52 and 11.92 mg g¯¹, respectively under a favourable sorption process. The dependency of BB3 and CR adsorption on temperature was validated by van’t Hoff equation. The effect of temperature on the BB3 and CR removal by PPS was ascertained by studying the temperature-dependence dyes distribution between bulk solution and adsorbent, and the interaction between dyes and adsorbent. Removal of BB3 and CR by PPS was found to be exothermic. The result suggests that PPS has higher affinity on cationic than anionic dye.

Single phase non-stoichiometric bismuth zinc niobate, Bi3Zn1.84Nb3O13.84, was fabricated by a conventional solid state method. The sample was refined and fully indexed on the cubic system, space group Fd3m (No. 227), Z = 4 with a = 10.5579(4) �. Electrical characterisation was performed using an ac impedance analyser over the temperature range of 25-850 �C and frequency range of 5 Hz-13 MHz. Typical dielectric response is observed in Bi3 Zn1.84Nb3O13.84 with a high relative permittivity, low dielectric loss and a negative temperature coefficient of capacitance, with the values of 147, 0.002 and -396 ppm/�C, at 100 kHz at ambient temperature, respectively. This material is highly resistive, with a conductivity of 1�10-21 O-1�cm-1 and a high activation energy of ca. 1.59 eV.

Single phase non-stoichiometric bismuth zinc niobate, Bi3Zn1.84Nb3O13.84, was fabricated by a conventional solid state method. The sample was refined and fully indexed on the cubic system, space group Fd3m (No. 227), Z = 4 with a = 10.5579(4) �. Electrical characterisation was performed using an ac impedance analyser over the temperature range of 25-850 �C and frequency range of 5 Hz-13 MHz. Typical dielectric response is observed in Bi3 Zn1.84Nb3O13.84 with a high relative permittivity, low dielectric loss and a negative temperature coefficient of capacitance, with the values of 147, 0.002 and -396 ppm/�C, at 100 kHz at ambient temperature, respectively. This material is highly resistive, with a conductivity of 1�10-21 O-1�cm-1 and a high activation energy of ca. 1.59 eV.

Sergestid shrimp Acetes intermedius was recorded for the first time from the Bintulu coastal waters in Sarawak. The morphological characters of the species were examined. Population structure, length-weight and length-length relationship of A. intermedius was estimated based on specimens collected from the site during February-March 2006. A total of 857 specimens (473 males and 384 females) of A. intermedius were measured for the study of size frequency structure. The mean length of the male and female was 25.6 ± 2.52 mm and 27.02 ± 3.24 mm, respectively. The sex ratio was found to be 1: 0.81 (males: females). Total length of female was on an average 1.41 mm longer than the male (P < 0.01). The equations calculated for length-weight relationship were W = 0.0025 TL3.1484 (r2 = 0.80) for male, W = 0.0033 L3.044 (r2 = 0.77) for female. The value of b for males (b = 3.148) and females (b = 3.044) were closest to 3 which was not significantly higher than isometric value (3) indicating that the growth in males and females were isometric. The estimated co efficient of correlation (r) between the total length and body weight was 0.99 for combined sexes of the species, indicating that the relationship was highly significant (P < 0.01).

Sergestid shrimp Acetes intermedius was recorded for the first time from the Bintulu coastal waters in Sarawak. The morphological characters of the species were examined. Population structure, length-weight and length-length relationship of A. intermedius was estimated based on specimens collected from the site during February-March 2006. A total of 857 specimens (473 males and 384 females) of A. intermedius were measured for the study of size frequency structure. The mean length of the male and female was 25.6 ± 2.52 mm and 27.02 ± 3.24 mm, respectively. The sex ratio was found to be 1: 0.81 (males: females). Total length of female was on an average 1.41 mm longer than the male (P < 0.01). The equations calculated for length-weight relationship were W = 0.0025 TL3.1484 (r2 = 0.80) for male, W = 0.0033 L3.044 (r2 = 0.77) for female. The value of b for males (b = 3.148) and females (b = 3.044) were closest to 3 which was not significantly higher than isometric value (3) indicating that the growth in males and females were isometric. The estimated co efficient of correlation (r) between the total length and body weight was 0.99 for combined sexes of the species, indicating that the relationship was highly significant (P < 0.01).