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Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo, Osun State, Nigeria

S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

《能源前沿(英文)》 2013年 第7卷 第2期   页码 214-222 doi: 10.1007/s11708-013-0241-2

摘要: In this study, the global solar radiation on horizontal surface in Osogbo, Osun state, Nigeria was analyzed using 11-year data (1997–2007). Correlations using linear and quadratic expressions were developed to relate the global solar radiation on horizontal surface based on relative sunshine hours and temperature measurements for evaluating the monthly average daily global solar radiation. The calculated monthly clearness index values indicate that the prevailing weather condition in Osogbo is heavily overcast. All the developed quadratic correlations gave better correlation coefficients (0.834, 0.872 and 0.823 respectively) than the linear models. However, the Hargreaves and Samani related based quadratic model gave the best among the three developed quadratic expressions and is therefore suggested for estimating the monthly global radiation in this site and its surroundings.

关键词: global solar radiation     Hargreaves model     sunshine hour     ambient temperatures     Osogbo    

Orderly decorated nanostructural photoelectrodes with uniform spherical TiO

M. Bakhshayesh,S. S. Azadfar

《化学科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 532-540 doi: 10.1007/s11705-015-1549-8

摘要: This study presents a novel nanostructural electrode made of 20-nm-diameter nanoparticles, which orderly decorated with 2-µm TiO particles, deposited by a new gel process. The decorated electrode (DE) is better than the non-decorated electrode (NE) in both light scattering and light harvesting, as confirmed by diffuse reflectance spectroscopy. X-ray diffraction reveals that both electrodes have a mixture of anatase and rutile phases. The dye-sensitized solar cell based on the decorated electrode shows the highest power conversion efficiency of 7.80% as a result of less recombination demonstrated by electrochemical impedance spectroscopy. From internal power conversion efficiency measurement, the external quantum efficiency of DE cell at 530 nm is 89%, which is higher than that of NE cell (77%).

关键词: dye-sensitized solar cell     uniform particles     TiO2 gel process     light harvesting    

Estimation of power in low velocity vertical axis wind turbine

Sampath S. S.,Sawan SHETTY,Chithirai Pon Selvan M.

《机械工程前沿(英文)》 2015年 第10卷 第2期   页码 211-218 doi: 10.1007/s11465-015-0338-x

摘要:

The present work involves in the construction of a vertical axis wind turbine and the determination of power. Various different types of turbine blades are considered and the optimum blade is selected. Mechanical components of the entire setup are built to obtain maximum rotation per minute. The mechanical energy is converted into the electrical energy by coupling coaxially between the shaft and the generator. This setup produces sufficient power for consumption of household purposes which is economic and easily available.

关键词: wind turbine     shaft design     power generation     generator    

Mechanical properties of steel, glass, and hybrid fiber reinforced reactive powder concrete

Atheer H.M. ALGBURI, M. Neaz SHEIKH, Muhammad N.S. HADI

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 998-1006 doi: 10.1007/s11709-019-0533-7

摘要: This study examines the properties of fiber-reinforced reactive powder concrete (FR-RPC). Steel fibers, glass fibers, and steel-glass hybrid fibers were used to prepare the FR-RPC. The non-fibrous reactive powder concrete (NF-RPC) was prepared as a reference mix. The proportion of fibers by volume for all FR-RPC mixes was 1.5%. Steel fibers of 13 mm length and 0.2 mm diameter were used to prepare the steel fiber-reinforced RPC (SFR-RPC). Glass fibers of 13 mm length and 1.3 mm diameter were used to prepare the glass fiber-reinforced RPC (GFR-RPC). The hybrid fiber-reinforced RPC (HFR-RPC) was prepared by mixing 0.9% steel fibers and 0.6% glass fibers. Compressive strength, axial load-axial deformation behavior, modulus of elasticity, indirect tensile strength, and shear strength of the RPC mixes were investigated. The results showed that SFR-RPC achieved higher compressive strength, indirect tensile strength and shear strength than NF-RPC, GFR-RPC, and HFR-RPC. Although the compressive strengths of GFR-RPC and HFR-RPC were slightly lower than the compressive strength of NF-RPC, the shear strengths of GFR-RPC and HFR-RPC were higher than that of NF-RPC.

关键词: reactive powder concrete     steel fiber     glass fiber     hybrid fiber    

Characterization and seasonal distribution of microplastics in the nearshore sediments of the south-east coast of India, Bay of Bengal

Dhineka , M. Sambandam , S. K. Sivadas , T.Kaviarasan , Umakanta Pradhan , Mehmuna Begum , Pravakar Mishra , M. V. Ramana Murthy

《环境科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 10-10 doi: 10.1007/s11783-021-1444-0

摘要:

In view of increasing Microplastics (MPs) contamination in the marine environment and dearth of baseline data, a study was conducted on the abundance, characterization, and seasonal distribution of MPs in the nearshore sediments of the south-east coast of India. Sediment samples (n = 130) were collected at a distance of 1 km and 10 km from the shore region at varying depths (8–45 m) along the Chennai to Puducherry coast (165 km stretch), representing two seasons, i.e., south-west (July 2019 and July 2020) and north-east (January 2020) monsoons. The average abundance of MPs at the 22 offshore sites along the Chennai to Puducherry coast varied from 9±4.3 to 19±12.9 particles/50 g dry weight, in July 2019 and January 2020, respectively. July 2020 had an average abundance of 10±4.5 particles/50 g dry weight. Spatially, high levels of MPs were found at 1km stations and transects in proximity to the river inlets, and temporally, the north-east month recorded the maximum concentration. The dominant morphotype was the filament, and the major polymers were polyethylene and polypropylene. Scanning Electron Microscope (SEM) images revealed the surface irregularity and degradation of MPs due to weathering. The study highlights that high sediment contamination by MPs occurs during heavy rainfall and accumulates closer to river inlets. Eventually, this study suggests that appropriate management of plastic wastes on the landside will reduce MP contamination in the marine environment.

Techno-economic evaluation of wind energy in southwest Nigeria

Muyiwa S. ADARAMOLA, Olarenwaju M. OYEWOLA, Olayinka S. OHUNAKIN, Rufus R. DINRIFO

《能源前沿(英文)》 2012年 第6卷 第4期   页码 366-378 doi: 10.1007/s11708-012-0205-y

摘要: In this study, an analysis of the wind energy potential in the southwest geo-political region of Nigeria was conducted. A 37-year (1971–2007) wind speed data set measured at 10 m height, obtained from eight meteorological stations within the region was analyzed using a 2-parameter Weibull function. Besides, a techno-economic evaluation of large wind energy conversion systems with power ratings ranging from 0.6 to 2 MW at different hub heights based on the levelized unit cost of electricity was made for the different sites considered. The result showed that electricity cost varied from 0.06997 and 0.11195 $/(kW·h) to 2.86611 and 4.58578 $/(kW·h) at limit values of turbine specific cost band intervals of 1000 and 1600 $/kW. It was further shown that Lagos, having the highest accumulated power outputs of 430.10 kW/a from DeWind D7 at 70 m hub height, is the most preferred for economically usable power generation in terms of the levelized unit cost.

关键词: mean wind speed     Weibull distributions     wind turbine     techno-economic analysis     southwest geopolitical region     Nigeria    

Investigation of wind energy potentials in Brunei Darussalam

M. A. SALAM, M. G. YAZDANI, Q. M. RAHMAN, Dk NURUL, S. F. MEI, Syeed HASAN

《能源前沿(英文)》 2019年 第13卷 第4期   页码 731-741 doi: 10.1007/s11708-018-0528-4

摘要: Conventional power generation mainly depends on natural gas and diesel oil in Brunei Darussalam. The power utility company is now thinking of power generation using natural wind. In this paper, wind energy, being one of the most readily available renewable energy sources, was studied. The wind characteristic, velocity and directions were studied using Weibull distribution based on the measurement of wind speed at two different locations in Brunei Darussalam. These wind speed distributions were modeled using the Wind Power program. The wind rose graph was obtained for the wind direction to analyze the wind power density onshore and offshore. Based on this analysis, it has been found that the wind speed of 3 to 5 m/s has a probability of occurrence of 40%. Besides, the annual energy production at a wind speed of 5 m/s has been found to be in the range between 1000 and 1500 kWh for both the locations in Brunei Darussalam.

关键词: wind speed     Weibull distribution     wind rose     wind energy     wind power    

Decoration of vertically aligned TiO

ISMAIL, M. S. AMIN, Mohamed MEKEWI

《能源前沿(英文)》 2018年 第12卷 第2期   页码 249-258 doi: 10.1007/s11708-018-0547-1

摘要: WO decorated photoelectrodes of titanium nanotube arrays (W-oxide TNTAs) were synthesized via a two-step process, namely, electrochemical oxidation of titanium foil and electrodeposition of W-oxide for various interval times of 1, 2, 3, 5, and 20 min to improve the photoelectrochemical performance and the amount of hydrogen generated. The synthesized photoelectrodes were characterized by various characterization techniques. The presence of tungsten in the modified TNTAs was confirmed using energy dispersive X-ray spectroscopy (EDX). Field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscope (HRTEM) proved the deposition of W-oxide as small particles staked up on the surface of the tubes at lower deposition time whereas longer times produced large and aggregate particles to mostly cover the surface of TiO nanotubes. Additionally, the incorporation of WO resulted in a shift of the absorption edge toward visible light as confirmed by UV-Vis diffuse reflectance spectroscopy and a decrease in the estimated band gap energy values hence, modified TNTAs facilitated a more efficient utilization of solar light for water splitting. From the photoelectrochemical measurement data, the optimal photoelectrode produced after 2 min of deposition time improved the photo conversion efficiency and the hydrogen generation by 30% compared to that of the pure TNTA.

关键词: titanium dioxide nanotube arrays     potentiostaticanodization     electrodeposition method     tungsten oxide     photoelectrochemical water splitting    

Planetary Homeostasis of Reactive Nitrogen Through Anaerobic Ammonium Oxidation

Guibing Zhu,Bangrui Lan,Shuci Liu,Cameron M.Callbeck,Shanyun Wang,Liping Jiang,Asheesh Kumar Yadav,Jan Vymazal,Mike S. M.

《工程(英文)》 doi: 10.1016/j.eng.2023.09.013

摘要: The availability of nitrogen (N) is crucial for both the productivity of terrestrial and aquatic ecosystems globally. However, the overuse of artificial fertilizers and the energy required to fix nitrogen have pushed the global nitrogen cycle (N-cycle) past its safe operating limits, leading to severe nitrogen pollution and the production of significant amounts of greenhouse gas nitrous oxide (N2O). The anaerobic ammonium oxidation (anammox) mechanism can counteract the release of ammonium and N2O in many oxygen-limited situations, assisting in the restoration of the homeostasis of the Earth’s N biogeochemistry. In this work, we looked into the characteristics of the anammox hotspots’ distribution across various types of ecosystems worldwide. Anammox hotspots are present at diverse oxic–anoxic interfaces in terrestrial systems, and they are most prevalent at the oxic–anoxic transition zone in aquatic ecosystems. Based on the discovery of an anammox hotspot capable of oxidizing ammonium anoxically into N2 without N2O by-product, we then designed an innovative concept and technical routes of nature-based anammox hotspot geoengineering for climate change, biodiversity loss, and efficient utilization of water resources. After 15 years of actual use, anammox hotspot geoengineering has proven to be effective in ensuring clean drinking water, regulating the climate, fostering plant and animal diversity, and enhancing long-term environmental quality. The sustainable biogeoengineering of anammox could be a workable natural remedy to resolve the conflicts between environmental pollution and food security connected to N management.

关键词: biogeochemical N-cycle     oxic–anoxic interface     nature-based solution     biogeoengineering     nitrogen sustainable development    

An investigation of reaction furnace temperatures and sulfur recovery

S. ASADI, M. PAKIZEH, M. POURAFSHARI CHENAR

《化学科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 362-371 doi: 10.1007/s11705-011-1106-z

摘要: In a modern day sulfur recovery unit (SRU), hydrogen sulfide (H S) is converted to elemental sulfur using a modified Claus unit. A process simulator called TSWEET has been used to consider the Claus process. The effect of the H S concentration, the H S/CO ratio, the input air flow rate, the acid gas flow of the acid gas (AG) splitter and the temperature of the acid gas feed at three different oxygen concentrations (in the air input) on the main burner temperature have been studied. Also the effects of the tail gas ratio and the catalytic bed type on the sulfur recovery were studied. The bed temperatures were optimized in order to enhance the sulfur recovery for a given acid gas feed and air input. Initially when the fraction of AG splitter flow to the main burner was increased, the temperature of the main burner increased to a maximum but then decreased sharply when the flow fraction was further increased; this was true for all three concentrations of oxygen. However, if three other parameters (the concentration of H S, the ratio H S/CO and the flow rate of air) were increased, the temperature of the main burner increased monotonically. This increase had different slopes depending on the oxygen concentration in the input air. But, by increasing the temperature of the acid gas feed, the temperature of the main burner decreased. In general, the concentration of oxygen in the input air into the Claus unit had little effect on the temperature of the main burner (This is true for all parameters). The optimal catalytic bed temperature, tail gas ratio and type of catalytic bed were also determined and these conditions are a minimum temperature of 300°C, a ratio of 2.0 and a hydrolysing Claus bed.

关键词: Claus unit     concentration of H2S     tail gas ratio     sulfur recovery     catalytic bed    

Sizing of hybrid PMSG-PV system for battery charging of electric vehicles

M. M. RAJAN SINGARAVEL,S. ARUL DANIEL

《能源前沿(英文)》 2015年 第9卷 第1期   页码 68-74 doi: 10.1007/s11708-015-0349-7

摘要: The number of electric vehicles are increasing in the society as they are considered as zero emission vehicles and also because conventional fuels are becoming expensive. Additional electrical power should be produced to meet the energy requirement of this increase in electric vehicle population. To use the existing grid infrastructure without any failure, installing distributed generator at secondary distribution network is essential. In this work, sizing of wind-driven permanent magnet synchronous generator—photovoltaic hybrid distributed generating system has been attempted to meet the energy demand of electric vehicles of a particular residential area. Different feasible combinations for wind generator capacity and photovoltaic capacity are obtained to satisfy the additional energy requirement. Results are analyzed based on energy, financial payback periods and daily power profile of the hybrid system. Based on this analysis, the sizes of wind generator and photovoltaic array have been chosen to meet the energy demand of electric vehicles of that particular residential locality.

关键词: electric vehicles     hybrid PMSG-PV system     smart grid    

Bismuth oxide-related photocatalysts in green nanotechnology: A critical analysis

Reverberi, P.S. Varbanov, M. Vocciante, B. Fabiano

《化学科学与工程前沿(英文)》 2018年 第12卷 第4期   页码 878-892 doi: 10.1007/s11705-018-1744-5

摘要: A survey addressing the uses of bismuth oxide in photocatalysis is presented. The richness of literature on such a specific topic proves the growing importance of this compound as a valid tool in pollution abatement and environmental decontamination. Many research groups have focused their activity on how to improve the photocatalytic properties of this semiconductor and several solutions have been adopted in the synthesis method, often based on wet-chemical processes. The impressive development of nanoscience helped in understanding and identifying process variables and operative conditions aiming at optimizing the yield of this promising photocatalytic material in the utilization of solar energy.

关键词: photocatalysis     visible light     bismuth compounds     nanotechnology     environmental remediation     decontamination     pollution abatement    

Kinematical synthesis of an inversion of the double linked fourbar for morphing wing applications

AVILéS, I. FERNáNDEZ, M. ABASOLO

《机械工程前沿(英文)》 2013年 第8卷 第1期   页码 17-32 doi: 10.1007/s11465-013-0364-5

摘要:

This paper presents the kinematical features of an inversion of the double linked fourbar for morphing wing purposes. The structure of the mechanism is obtained using structural synthesis concepts, from an initial conceptual schematic. Then, kinematic characteristics as instant center of rotation, lock positions, dead point positions and uncertainty positions are derived for this mechanism in order to face the last step, the dimensional synthesis; in this sense, two kinds of dimensional synthesis are arranged to guide the wing along two positions, and to fulfill with the second one some aerodynamic and minimum actuation energy related issues.

关键词: morphing wing     structural synthesis     dimensional synthesis     geometrical kinematics    

Effect of the degree of template removal from mesoporous silicate materials on their adsorption of heavy oil from aqueous solution

Farouq TWAIQ,M.S. NASSER,Sagheer A. ONAIZI

《化学科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 488-497 doi: 10.1007/s11705-014-1459-1

摘要: The key aim of this study is to evaluate the adsorption of heavy oil from aqueous solutions with different oil contents over mesoporous silicate materials having different surfactant template contents. The mesoporous silicate materials have been synthesized from tetraethylorthosilicate as a silica precursor and cetyltrimethylammonium bromide as a template using the sol-gel technique. Four samples were prepared by (1) totally removing the template using the calcination process, (2) partially removing the template via ethanol extraction, (3) partially removing the template via water extraction, and (4) keeping the template as synthesized, respectively. These four samples have been characterized using X-ray diffraction, nitrogen adsorption, thermal gravimetric analysis and Fourier transformed infrared. The effect of the degree of template removal of these mesoporous materials for the oil removal has been investigated. The oil removal is inversely proportional to the surfactant content in the mesoporous material, being highest for the calcined sample but lowest for the as-synthesized sample. The kinetic of oil adsorption over the calcined material has been also studied and the data obtained fit well a second-order model.

关键词: heavy oil     mesoporous silicate material     kinetics     template removal     adsorption    

Critical review of recent development in fiber reinforced adobe bricks for sustainable construction

Mahgoub M. SALIH, Adelaja I. OSOFERO, Mohammed S. IMBABI

《结构与土木工程前沿(英文)》 2020年 第14卷 第4期   页码 839-854 doi: 10.1007/s11709-020-0630-7

摘要: This paper presents a state-of-the-art review of research on the utilization of fibers (predominantly derived from waste materials) as reinforcement in adobe brick production. Recycling of these wastes provides sustainable construction materials and helps to protect the environment. Specimen preparation and test procedures are outlined. The effects of addition of these wastes on the physical and mechanical properties of adobe bricks as presented in the literature, are investigated. The main results for each additive are presented and discussed. It is concluded that improved adobe brick properties can be expected with the addition of combination of waste additives. The use of waste materials in the construction industry is generally of interest and useful for engineers and designers seeking sustainable solutions in construction. It is also of interest to researchers actively seeking to develop methodical approaches to quantifying, optimising and testing the performance in use of such waste material additives.

关键词: adobe bricks     fibre reinforced bricks     green     sustainable building material     physical and mechanical properties    

标题 作者 时间 类型 操作

Correlations for estimating solar radiation using sunshine hours and temperature measurement in Osogbo, Osun State, Nigeria

S. OHUNAKIN, M. S. ADARAMOLA, O. M. OYEWOLA, R. O. FAGBENLE

期刊论文

Orderly decorated nanostructural photoelectrodes with uniform spherical TiO

M. Bakhshayesh,S. S. Azadfar

期刊论文

Estimation of power in low velocity vertical axis wind turbine

Sampath S. S.,Sawan SHETTY,Chithirai Pon Selvan M.

期刊论文

Mechanical properties of steel, glass, and hybrid fiber reinforced reactive powder concrete

Atheer H.M. ALGBURI, M. Neaz SHEIKH, Muhammad N.S. HADI

期刊论文

Characterization and seasonal distribution of microplastics in the nearshore sediments of the south-east coast of India, Bay of Bengal

Dhineka , M. Sambandam , S. K. Sivadas , T.Kaviarasan , Umakanta Pradhan , Mehmuna Begum , Pravakar Mishra , M. V. Ramana Murthy

期刊论文

Techno-economic evaluation of wind energy in southwest Nigeria

Muyiwa S. ADARAMOLA, Olarenwaju M. OYEWOLA, Olayinka S. OHUNAKIN, Rufus R. DINRIFO

期刊论文

Investigation of wind energy potentials in Brunei Darussalam

M. A. SALAM, M. G. YAZDANI, Q. M. RAHMAN, Dk NURUL, S. F. MEI, Syeed HASAN

期刊论文

Decoration of vertically aligned TiO

ISMAIL, M. S. AMIN, Mohamed MEKEWI

期刊论文

Planetary Homeostasis of Reactive Nitrogen Through Anaerobic Ammonium Oxidation

Guibing Zhu,Bangrui Lan,Shuci Liu,Cameron M.Callbeck,Shanyun Wang,Liping Jiang,Asheesh Kumar Yadav,Jan Vymazal,Mike S. M.

期刊论文

An investigation of reaction furnace temperatures and sulfur recovery

S. ASADI, M. PAKIZEH, M. POURAFSHARI CHENAR

期刊论文

Sizing of hybrid PMSG-PV system for battery charging of electric vehicles

M. M. RAJAN SINGARAVEL,S. ARUL DANIEL

期刊论文

Bismuth oxide-related photocatalysts in green nanotechnology: A critical analysis

Reverberi, P.S. Varbanov, M. Vocciante, B. Fabiano

期刊论文

Kinematical synthesis of an inversion of the double linked fourbar for morphing wing applications

AVILéS, I. FERNáNDEZ, M. ABASOLO

期刊论文

Effect of the degree of template removal from mesoporous silicate materials on their adsorption of heavy oil from aqueous solution

Farouq TWAIQ,M.S. NASSER,Sagheer A. ONAIZI

期刊论文

Critical review of recent development in fiber reinforced adobe bricks for sustainable construction

Mahgoub M. SALIH, Adelaja I. OSOFERO, Mohammed S. IMBABI

期刊论文