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Fulltext Impact of coal rents, transportation, electricity consumption, and economic globalization on ecological footprint in the USA

Wenlong Z, Nawaz MA, Sibghatullah A, Ullah SE, Chupradit S, Minh Hieu V

Environ Sci Pollut Res Int, 2023 Mar;30(15):43040-43055.
PMID: 35501438 DOI: 10.1007/s11356-022-20431-7

Over the last three decades, the world has been facing the phenomenon of the ecological deficit as the ecological footprint is continuously rising due to the persistent decline of the per-capita bio-capacity. Moreover, there is a substantial increase in globalization and electricity consumption for the same period, and transportation is contributing to economic prosperity at the cost of environmental sustainability. Understanding the determinants of ecological footprint is thus critical for suggesting appropriate policies for environmental sustainability. As a result, this study analyzes the impacts of economic globalization, transportation, coal rents, and electricity consumption in ecological footprint in the context of the USA over the period 1995 to 2018. The data have been extracted from "Global Footprint Network," "Swiss Economic Institute," and "World Development Indicators." The current study has also applied the flexible Fourier form nonlinear unit root test to examine the stationarity among variables. For the empirical estimation, a novel technique, the "quantile auto-regressive distributive lag model," is applied in the study to deal with the nonlinear associations of the variables and to evaluate the long-term stability of variables across quantiles. The study's findings indicate that coal rents, transportation, and globalization significantly and positively contribute to the deterioration of ecological footprints at different quantile ranges in the short and long run. Electricity consumption is found to have a positive and significant impact at lower quantile ranges in the long run but not have a significant impact in the short run. The study suggested that lowering the dependence of the transport sector on fossil fuels, more use of hydroelectricity, and stringent strategies to curb coal consumption would be helpful to reduce the positive influence of these variables on ecological footprints in the USA.

Matched MeSH terms: Electricity
On the physics of ferroelectrics

Webb JF

Sci Prog, 2003;86(Pt 3):203-34.
PMID: 15079997

The main physical properties of ferroelectric crystals are described, and the macroscopic and microscopic viewpoints are discussed along with some applications, such as in capacitors and nonlinear optics. The emphasis is on physical understanding, while the mathematical level is kept to a minimum or supplemented by graphical representations to make the article more accessible.

Matched MeSH terms: Static Electricity*
Constructed wetland integrated microbial fuel cell system: looking back, moving forward

Wang Y, Zhao Y, Xu L, Wang W, Doherty L, Tang C, et al.

Water Sci Technol, 2017 Jul;76(2):471-477.
PMID: 28726712 DOI: 10.2166/wst.2017.190

In the last 10 years, the microbial fuel cell (MFC) has been extensively studied worldwide to extract energy from wastewater via electricity generation. More recently, a merged technique of embedding MFC into a constructed wetland (CW) has been developed and appears to be increasingly investigated. The driving force to integrate these two technologies lies in the fact that CWs naturally possess a redox gradient (depending on flow direction and wetland depth), which is required by MFCs as anaerobic anode and aerobic cathode chambers. No doubt, the integration of MFC with a CW will upgrade the CW to allow it to be used for wastewater treatment and, simultaneously, electricity generation, making CWs more sustainable and environmentally friendly. Currently, published work shows that India, China, Ireland, Spain, Germany and Malaysia are involved in the development of this technology although it is in its infant stage and many technical issues are faced on system configuration, operation and maximisation of electricity production. This paper aims to provide an updated review and analysis of the CW-MFC development. Focuses are placed on the experience gained so far from different researchers in the literature and further research directions and proposals are discussed in great detail.

Matched MeSH terms: Electricity
Application of interface material and effects of oxygen gradient on the performance of single-chamber sediment microbial fuel cells (SSMFCs)

Wang CT, Sangeetha T, Yan WM, Chong WT, Saw LH, Zhao F, et al.

J Environ Sci (China), 2019 Jan;75:163-168.
PMID: 30473281 DOI: 10.1016/j.jes.2018.03.013

Single-chamber sediment microbial fuel cells (SSMFCs) have received considerable attention nowadays because of their unique dual-functionality of power generation and enhancement of wastewater treatment performance. Thus, scaling up or upgrading SSMFCs for enhanced and efficient performance is a highly crucial task. Therefore, in order to achieve this goal, an innovative physical technique of using interface layers with four different pore sizes embedded in the middle of SSMFCs was utilized in this study. Experimental results showed that the performance of SSMFCs employing an interface layer was improved regardless of the pore size of the interface material, compared to those without such layers. The use of an interface layer resulted in a positive and significant effect on the performance of SSMFCs because of the effective prevention of oxygen diffusion from the cathode to the anode. Nevertheless, when a smaller pore size interface was utilized, better power performance and COD degradation were observed. A maximum power density of 0.032mW/m2 and COD degradation of 47.3% were obtained in the case of an interface pore size of 0.28μm. The findings in this study are of significance to promote the future practical application of SSMFCs in wastewater treatment plants.

Matched MeSH terms: Electricity
Optimal aeration area of cathode electrode in the batch type of microbial fuel cells with non-woven interface

Wang CT, Ubando AT, Wan ML, Ong Tang RC

Chemosphere, 2023 Oct;337:139257.
PMID: 37343634 DOI: 10.1016/j.chemosphere.2023.139257

Microbial fuel cells (MFCs) are based on the biochemical reaction of microorganisms to decompose organic wastewater for converting chemical energy into power energy. MFCs are considered an environmentally friendly technology that is gaining popularity due to their simultaneous digestion and energy production abilities. To enhance its real application in wastewater treatment, this study proposes to use a non-woven material for replacing the usage of expensive membranes in MFCs. In addition, the study aims to consider a series of different aeration areas of cathode electrodes for finding an optional design. Results have shown that the adoption of non-woven with 0.45 μm can effectively prohibit the diffusion of oxygen into the anode chamber. Moreover, the non-woven material played an important role as an interface between the anode and cathode, enhancing the MFC performance. The usage of suitable non-woven material can replace the role of the membrane when applied in real wastewater applications. The results have shown that the case study where a combination of a 50% aeration area of the cathode electrodes with 25% exposure of the cathode plate in the air yielded relatively better aeration in terms of a higher current density of 250 mA/m2, higher power density of 220 mW/m2, and higher open voltage circuit of 0.4 V, compared to other case studies considered. These results indicate the optimal aeration configuration for MFCs applied in commercial wastewater treatment in the future.

Matched MeSH terms: Electricity
Fulltext The development of a power recycling prototype for renewable energy using dc motor

Wan Nor Shela Ezwane Wan Jusoh, Md Razak Daud

Journal of Engineering and Science Research, 2018;2(6):50-54.
MyJurnal

Energy consumption is an important part of life today because without the power a work cannot be done. The energy used today will be lost or waste without renewable energy or power recycle back. In reality, energy use has always had a noticeable impact on the environment. Overconsumption of energy is the main trigger for the global warming that is now threatening to cause devastation in many areas of the world. Each year, electricity consumption in Malaysia is always an increase. This can contribute to the occurrence of global warming. This project will be designed for renewable energy or recycle power to avoid waste of energy from lost. Also, this project consider regarding the Green Technology without polluting the environment. The objective is to develop a prototype or hardware that aims to renewable energy using the 12V DC Motor as a generator which is use rear shaft of table fan as a medium to drive the 12V DC Motor and also to analyze the power consumption of table fan before and after install with hardware. The methods used to design the connector and DC motor holder is using a solidwork software, then construct the circuit simulation using a proteus software and also use a microcontroller PIC16F877A as a controller. The result obtained from the testing and experiments by integrating the hardware part, electrical part and software part. Finally, with the development of a power recycling prototype for renewable energy using DC Motor application, the wasted energy can be reused from conversion to other energy and energy can be used as renewable energy.

Matched MeSH terms: Electricity
Fulltext Data on greenhouse gases emission of fuels in power plants in Malaysia during the year of 1990-2017

Wan Mansor WN, Abdullah S, Che Wan Othman CWMN, Jarkoni MNK, Chao HR, Lin SL

Data Brief, 2020 Jun;30:105440.
PMID: 32300616 DOI: 10.1016/j.dib.2020.105440

Energy has a significant influence on Malaysia's industry. It is used in electricity generation, refineries, gas processing plants and end-user applications such as transportation, residential, agriculture and fishing. These burning fossil fuel activities produce greenhouse gases (GHG) emissions. This article presents the emissions data of fuel used in power plants in Malaysia during the year of 1990 until 2017. The fuel used in power plants is coal and coke, natural gas, diesel oil and residual fuel oil. The energy data used in power plants were gathered from the Malaysia Energy Information Hub, published by the Malaysian Energy Commission. The GHG emissions data were calculated using the emission factors method. The climate impact of different GHGs in terms of CO2-equivalent (CO2-e) was also calculated using global warming potentials. The article also presents population data in Malaysia during the year. A correlation between the fuels, GHG emission and the population is also investigated using statistical analysis. The data presented here may facilitate the Malaysian government to identify the source of the pollutants and undertake a climate change mitigation plan.

Matched MeSH terms: Electricity
Fulltext Elucidating mesomorphic and electrical properties of conjugated acetylide-imine as electrochemically deposited electron transporting materials in organic conductive film

Wan M. Khairul, Foong, Y.D., Lee, O.J., Lim, S.K.J., Daud, A.I., Rahamathullah, R., et al.

ASM Science Journal, 2018;11(101):124-135.
MyJurnal

A new class of liquid crystalline acetylide-imine system was successfully synthesized, characterized
and deposited on indium tin oxide (ITO) coated substrate via electrochemical deposition
method for potential organic film application. The relationship between liquid crystal
molecular structure, phase transition temperature and electrical performance was evaluated.
The mesomorphic properties were identified via polarized optic microscopy (POM) which displayed
fan-shaped texture of smectic A phase and their corresponding transition enthalpies
are in concurrence with DSC and TGA studies. The findings from the conductivity analysis
revealed that the fabricated film exhibits good electrical performance where it displayed
linear current-voltage relationship of I-V curve. Therefore, this proposed type of molecular
framework has given an ideal indication to act as transporting material for application in
optoelectronic devices.

Matched MeSH terms: Electricity
Reducing charging effects in scanning electron microscope images by Rayleigh contrast stretching method (RCS)

Wan Ismail WZ, Sim KS, Tso CP, Ting HY

Scanning, 2011 Jul-Aug;33(4):233-51.
PMID: 21611953 DOI: 10.1002/sca.20237

To reduce undesirable charging effects in scanning electron microscope images, Rayleigh contrast stretching is developed and employed. First, re-scaling is performed on the input image histograms with Rayleigh algorithm. Then, contrast stretching or contrast adjustment is implemented to improve the images while reducing the contrast charging artifacts. This technique has been compared to some existing histogram equalization (HE) extension techniques: recursive sub-image HE, contrast stretching dynamic HE, multipeak HE and recursive mean separate HE. Other post processing methods, such as wavelet approach, spatial filtering, and exponential contrast stretching, are compared as well. Overall, the proposed method produces better image compensation in reducing charging artifacts.

Matched MeSH terms: Static Electricity
Fulltext Design and development of eggplant harvester for gantry system

Wan Ishak, W.I., Kit, W.H., Awwal, M. A.

Pertanika Journal of Science & Technology, 2010;18(2):-.
MyJurnal

This paper describes the design and development of harvesting system for the gantry system to harvest eggplants. For this purpose, the harvesting robot was successfully designed and fabricated for the gantry system to harvest eggplants. The operation of the harvester was controlled by Programmable Logic Controller (PLC). Basically, the limit switches, DC motor, and relay are connected to the PLC. Meanwhile, a PLC ladder diagram was designed and developed to control the operation of the eggplant harvester. A visual basic programme was developed to interface the harvester with a greenhouse gantry control system. A videogrammetry method was employed to calculate the distance between the stems of eggplants and the cutter of robot end effector. The end effector used electric as its power source and it was controlled via Programmable Logic Controller (PLC). Visual Basic Programme was developed to interface the harvester with the gantry control system. The accuracy of the videogrammetry was tested to be 67.2% for X-axis, 88.2% for Y-axis and 84.7% for Z-axis. Meanwhile, the speed of the end effector for harvester is 2.4 km/h and it could lift up to 55 cm. In order to determine detachment force of eggplant, 16 samples of mature eggplants were tested in a greenhouse, and as a result, more than 22.76 N force was needed to detach a mature eggplant inside the gantry system.

Matched MeSH terms: Electricity
Fulltext Online Learning Approach for Predictive Real-Time Energy Trading in Cloud-RANs

Wan Ariffin WNSF, Zhang X, Nakhai MR, Rahim HA, Ahmad RB

Sensors (Basel), 2021 Mar 25;21(7).
PMID: 33806215 DOI: 10.3390/s21072308

Constantly changing electricity demand has made variability and uncertainty inherent characteristics of both electric generation and cellular communication systems. This paper develops an online learning algorithm as a prescheduling mechanism to manage the variability and uncertainty to maintain cost-aware and reliable operation in cloud radio access networks (Cloud-RANs). The proposed algorithm employs a combinatorial multi-armed bandit model and minimizes the long-term energy cost at remote radio heads. The algorithm preschedules a set of cost-efficient energy packages to be purchased from an ancillary energy market for the future time slots by learning both from cooperative energy trading at previous time slots and by exploring new energy scheduling strategies at the current time slot. The simulation results confirm a significant performance gain of the proposed scheme in controlling the available power budgets and minimizing the overall energy cost compared with recently proposed approaches for real-time energy resources and energy trading in Cloud-RANs.

Matched MeSH terms: Electricity
The energy cost of water independence: the case of Singapore

Vincent L, Michel L, Catherine C, Pauline R

Water Sci Technol, 2014;70(5):787-94.
PMID: 25225924 DOI: 10.2166/wst.2014.290

Finding alternative resources to secure or increase water availability is a key issue in most urban areas. This makes the research of alternative and local water resources of increasing importance. In the context of political tension with its main water provider (Malaysia), Singapore has been implementing a comprehensive water policy for some decades, which relies on water demand management and local water resource mobilisation in order to reach water self-sufficiency by 2060. The production of water from alternative resources through seawater desalination or water reclamation implies energy consumptive technologies such as reverse osmosis. In the context of increasing energy costs and high primary energy dependency, this water self-sufficiency objective is likely to be an important challenge for Singapore. The aim of this paper is to quantify the long-term impact of Singapore's water policy on the national electricity bill and to investigate the impact of Singapore's projects to reduce its water energy footprint. We estimate that 2.0% of the Singaporean electricity demand is already dedicated to water and wastewater treatment processes. If its water-energy footprint dramatically increases in the coming decades, ambitious research projects may buffer the energy cost of water self-sufficiency.

Matched MeSH terms: Electricity
A new thio-Schiff base fluorophore with copper ion sensing, DNA binding and nuclease activity

Vikneswaran R, Syafiq MS, Eltayeb NE, Kamaruddin MN, Ramesh S, Yahya R

Spectrochim Acta A Mol Biomol Spectrosc, 2015 Nov 5;150:175-80.
PMID: 26046495 DOI: 10.1016/j.saa.2015.05.087

Copper ion recognition and DNA interaction of a newly synthesized fluorescent Schiff base (HPyETSC) were investigated using UV-vis and fluorescent spectroscopy. Examination using these two techniques revealed that the detection of copper by HPyETSC is highly sensitive and selective, with a detection limit of 0.39 μm and the mode of interaction between HPyETSC and DNA is electrostatic, with a binding constant of 8.97×10(4) M(-1). Furthermore, gel electrophoresis studies showed that HPyETSC exhibited nuclease activity through oxidative pathway.

Matched MeSH terms: Static Electricity
Fulltext QSAR Studies on Neuraminidase Inhibitors as Anti-influenza Agents

Veerasamy R, Rajak H

Turk J Pharm Sci, 2021 04 20;18(2):151-156.
PMID: 33900700 DOI: 10.4274/tjps.galenos.2020.45556

Objectives: The present study aimed to establish significant and validated quantitative structure-activity relationship (QSAR) models for neuraminidase inhibitors and correlate their physicochemical, steric, and electrostatic properties with their anti-influenza activity.
Materials and Methods: We have developed and validated 2D and 3D QSAR models by using multiple linear regression, partial least square regression, and k-nearest neighbor-molecular field analysis methods.
Results: 2D QSAR models had q2: 0.950 and pred_r2: 0.877 and 3D QSAR models had q2: 0.899 and pred_r2: 0.957. These results showed that the models werere predictive.
Conclusion: Parameters such as hydrogen count and hydrophilicity were involved in 2D QSAR models. The 3D QSAR study revealed that steric and hydrophobic descriptors were negatively contributed to neuraminidase inhibitory activity. The results of this study could be used as platform for design of better anti-influenza drugs.

Matched MeSH terms: Static Electricity
Bioelectricity production and xylene biodegradation through double chamber benthic microbial fuel cells fed with sugarcane waste as a substrate

Umar MF, Rafatullah M, Abbas SZ, Ibrahim MNM, Ismail N

J Hazard Mater, 2021 10 05;419:126469.
PMID: 34192640 DOI: 10.1016/j.jhazmat.2021.126469

Xylene, a recalcitrant compound present in wastewater from activities of petrochemical and chemical industries causes chronic problems for living organisms and the environment. Xylene contaminated wastewater may be biodegraded through a benthic microbial fuel cell (BMFC) as seen in this study. Xylene was oxidized into intermediate 3-methyl benzoic acid and entirely converted into non-toxic carbon dioxide. The highest voltage of the BMFC reactor was generated at 410 mV between 23 and 90 days when cell potential was 1 kΩ. The reactor achieved a maximum power density of about 63 mW/m2, and a current of 0.4 mA which was optimized from variable resistance (20 Ω - 1 kΩ). However, the maximum biodegradation efficiency of the BMFC was at 87.8%. The cyclic voltammetry curve helped to determine that the specific capacitance was 0.124 F/g after 30 days of the BMFC operation. Furthermore, the fitting equivalent circuit was observed with the help of Nyquist plot for calculating overall internal resistance of 65.82 Ω on 30th day and 124.5 Ω on 80th day. Staphylococcus edaphicus and Staphylococcus sparophiticus were identified by 16S rRNA sequencing as the dominant species in the control and BMFC electrode, presumably associated with xylene biodegradation.

Matched MeSH terms: Electricity
Dynamic Absorption Enhancement and Equivalent Resonant Circuit Modeling of Tunable Graphene-Metal Hybrid Antenna

Ullah Z, Nawi I, Witjaksono G, Tansu N, Khattak MI, Junaid M, et al.

Sensors (Basel), 2020 Jun 04;20(11).
PMID: 32512718 DOI: 10.3390/s20113187

Plasmonic antennas are attractive optical components of the optoelectronic devices, operating in the far-infrared regime for sensing and imaging applications. However, low optical absorption hinders its potential applications, and their performance is limited due to fixed resonance frequency. In this article, a novel gate tunable graphene-metal hybrid plasmonic antenna with stacking configuration is proposed and investigated to achieve tunable performance over a broad range of frequencies with enhanced absorption characteristics. The hybrid graphene-metal antenna geometry is built up with a hexagon radiator that is supported by the Al2O3 insulator layer and graphene reflector. This stacked structure is deposited in the high resistive Si wafer substrate, and the hexagon radiator itself is a sandwich structure, which is composed of gold hexagon structure and two multilayer graphene stacks. The proposed antenna characteristics i.e., tunability of frequency, the efficiency corresponding to characteristics modes, and the tuning of absorption spectra, are evaluated by full-wave numerical simulations. Besides, the unity absorption peak that was realized through the proposed geometry is sensitive to the incident angle of TM-polarized incidence waves, which can flexibly shift the maxima of the absorption peak from 30 THz to 34 THz. Finally, an equivalent resonant circuit model for the investigated antenna based on the simulations results is designed to validate the antenna performance. Parametric analysis of the proposed antenna is carried out through altering the geometric parameters and graphene parameters in the Computer Simulation Technology (CST) studio. This clearly shows that the proposed antenna has a resonance frequency at 33 THz when the graphene sheet Fermi energy is increased to 0.3 eV by applying electrostatic gate voltage. The good agreement of the simulation and equivalent circuit model results makes the graphene-metal antenna suitable for the realization of far-infrared sensing and imaging device containing graphene antenna with enhanced performance.

Matched MeSH terms: Static Electricity
Radar return reduction for wind turbines using bump structures

Ueng SK, Chan Yao-Hong, Lu WH, Chang HW

Sains Malaysiana, 2015;44:1701-1706.

Wind turbines are massive electrical structures. They produce large returns when illuminated by radar waves. These
scatterings have a great impact on the operation of surveillance, air traffic control and weather radars. This paper presents
two geometric modelling methods for reshaping wind turbine towers so that the Radar Cross Section (RCS) of wind turbines
is reduced. In the proposed reshaping methods, bump structures are created on the surface of the conventional cylinder
wind turbine tower. When a reshaped tower is illuminated by radar waves, the bump structures scatter incident radar
waves into insignificant directions so that the strength of back-scattering is declined and the RCS of the wind turbine is
decreased. The test results confirmed that the proposed methodssignificantly reduce bi-static RCS values of wind turbines.
The proposed reshaping methods are practical, flexible and effective in alleviating the scatterings of wind turbines.

Matched MeSH terms: Electricity
Production and characterization of graphene from carbonaceous rice straw by cost-effect extraction

Uda MNA, Gopinath SCB, Hashim U, Halim NH, Parmin NA, Uda MNA, et al.

3 Biotech, 2021 May;11(5):205.
PMID: 33868892 DOI: 10.1007/s13205-021-02740-9

This paper describes the synthesis of graphene-based activated carbon from carbonaceous rice straw fly ash in an electrical furnace and the subsequent potassium hydroxide extraction. The produced graphene has a proper morphological structure; flakes and a rough surface can be observed. The average size of the graphene was defined as up to 2000 nm and clarification was provided by high-resolution microscopes (FESEM and FETEM). Crystallinity was confirmed by surface area electron diffraction. The chemical bonding from the graphene was clearly observed, with -C=C- and O-H stretching at peaks of 1644 cm-1 and 3435 cm-1, respectively. Impurities in the graphene were found using X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The measured size, according to zeta-potential analysis, was 8722.2 ± 25 nm, and the average polydispersity index was 0.576. The stability of the mass reduction was analyzed by a thermogravimetric at 100 °C, with a final reduction of ~ 11%.

Matched MeSH terms: Electricity
Fulltext Novel modulation method for multidirectional matrix converter

Toosi S, Misron N, Hanamoto T, Bin Aris I, Radzi MA, Yamada H

ScientificWorldJournal, 2014;2014:645734.
PMID: 25298969 DOI: 10.1155/2014/645734

This study presents a new modulation method for multidirectional matrix converter (MDMC), based on the direct duty ratio pulse width modulation (DDPWM). In this study, a new structure of MDMC has been proposed to control the power flow direction through the stand-alone battery based system and hybrid vehicle. The modulation method acts based on the average voltage over one switching period concept. Therefore, in order to determine the duty ratio for each switch, the instantaneous input voltages are captured and compared with triangular waveform continuously. By selecting the proper switching pattern and changing the slope of the carriers, the sinusoidal input current can be synthesized with high power factor and desired output voltage. The proposed system increases the discharging time of the battery by injecting the power to the system from the generator and battery at the same time. Thus, it makes the battery life longer and saves more energy. This paper also derived necessary equation for proposed modulation method as well as detail of analysis and modulation algorithm. The theoretical and modulation concepts presented have been verified in MATLAB simulation.

Matched MeSH terms: Electricity*
Fabrication and morphological characterization of hybrid polymeric solar cells based on P3HT and inorganic nanocrystal blends

Toong WY, Khaulah Sulaiman

Sains Malaysiana, 2011;40.

In this research we investigated the effect of composition on the fabrication and morphological characteristics of a hybrid polymeric solar cell which consists of an electron donating conjugated polymer, namely is poly(3-hexylthiophene) (P3HT) combined with an electron-accepting component, which is a type of inorganic compound of TiO2 nanocrystals. The composition of TiO2 in the blends is varied and the optimum performance of the devices are studied. The optical and morphological characterizations are carried out via UV-Visible absorption spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM). The electrical characteristics of the devices are measured by using Keithley 2400 SMU and solar simulator with light intensity of 100 mW/cm2.

Matched MeSH terms: Electricity

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