bluuebunny/crossref_metadata_2025 huggingface dataset:
Stress analysis of a rack gear on sea wave power plant design in Bangka Island
Authors: Rosa F , Prayitnoadi R P
Published: November 2020

Bangka Island is one of the islands in Indonesia which has the potential of marine energy resources. One of the energies is ocean waves that can be used as an alternative to renewable energy in the design of mini power plants. The mechanic system flow that can be applied is sea wave drives float and then it drives a transmission element. Element transmission will rotate the generator that connected by a shaft. The element transmission that used in the plants is rack and pinion gear. This research conducted static analysis software using the von mises and safety factor method on rack and pinion gear. Based on research data, wave data at the headland of a bonded coast in Central Bangka Regency in January 2019 with a maximum wave height of 1,220 m and a minimum of 0.285 m. The force assessment that occurs on the buoy is based on the wave force with a maximum wave height of 287.19 N and the buoyancy force. From the highest height the maximum force obtained at the buoy is 689.54 N and vice versa the weight of the buoy mass. From the analysis using Autodesk Inventor software, it was found that the maximum stress that occurs in pinion gears is 53.14 MPa smaller than the yield strength material and the safety factor that occurs a minimum of 6.59 is greater than the safety factor allowed so that the rack and pinion gear can accept the force exerted by the waves.
Solar Energy Potential Mapping around Yogyakarta Palace As an Effort in Integrating Renewable Energy into Cultural Based Economic Development
Authors: Budiarto R , Dewanto B G , Novitasari D , Aliyah F
Published: November 2020

The Yogyakarta Palace is the main heritage buildings in Yogyakarta Province. It is a main cultural symbol, which is also one of the main tourism objects. This research focuses on The Palace main buildings and surrounding area as an effort to integrate acceleration of renewable energy use into the cultural-based economic development. It considers cross-cutting issues in integrating engineering approach within a complex socio-culture context. The research applied distribution of solar energy potential mapping by using analysis of 3D buildings data in the Open Street Map (OSM), Digital Elevation Model (DEM) and solar intensity data. QGIS software was applied to analyze the 3D buildings data and geospatial aspect. The research also provides a classification of solar energy potential. The mapping shows valuable capacity of The Palace and its surrounding area to produce electricity by the PV technology. Implementing, for instance, the Building Integrated Photovoltaics (BIPV) method in selected buildings, could provide encouraging environment for green tourism in a city of culture melting point as well as increase of renewable energy role and economic development. However, in such delicate issue of PV implementation the mapping and installation works would be far simpler tasks compared to the required intensive socio-culture inclusive process.
Review design of E-Motorcycle charger topology for DC house using planar magnetics
Authors: Muhammad D C , Alfath M I , Naradhipa A M , Husnayain F , Ardita I M
Published: November 2020

Following the global trend of adopting renewable energy into the electric power system, many direct currents (DC) houses concepts are proposed. Most of the renewable energy systems are based on DC voltage sources. This paper discussed the development of a lightweight, low-profile, and built-in electric motorcycle (E-Motorcycle) charger that does not take excessive space and compatible with the DC house system. A topology comparison in high switching frequency above 1 MHz using planar magnetics is performed to select the most suitable DC-DC converter. A wide bandgap (WBG) devices are used to achieve high efficiency in high switching frequency and reduce the charger’s size. Simulation results and design of the selected topology is presented.
Optimization of Battery Energy Storage System (BESS) sizing for solar power plant at remote area
Authors: Baghta N A , Aprilianti K P , Aryani D R , Jufri F H , Utomo A R
Published: November 2020

It is known that the availability of electrical energy will boost economic growth and also industrial growth. However, because the geographical location of the remote area is relatively isolated, the community’s energy demand in the area cannot be fulfilled. Until now, the majority of operated power plants are diesel generator by using fossil fuels. Hence, the addition of renewable energy sources (RESs), especially solar energy (PV) and Battery Energy Storage System (BESS) become a choice to reduce the use of fossil fuels. This study discusses the sizing of BESS and PV to obtain an optimized configuration that maximizes the penetration of RESs and minimizes the utilization of diesel generator. The method of this study will be done by using data from the remote area with simulation and computation using HOMER that can get the best configuration of the system. Thus, the results of this study can be implemented in those areas either at the present or in the future.
Modelling of photovoltaic system power prediction based on environmental conditions using neural network single and multiple hidden layers
Authors: Azka R , Soefian W , Aryani D R , Jufri F H , Utomo A R
Published: November 2020

The solar power plant is an alternative to the provision of environmentally friendly renewable electricity, especially in the tropics, which are sufficiently exposed to the sun throughout the year. However, environmental conditions such as rainfall, solar radiation, or clouds may affect the output power of photovoltaic (PV) systems. These factors make it difficult to know whether PV can meet the needs of the existing load. This research develops a model to predict the output power of a 160 x 285W PV system located in the tropics and has certain environmental conditions. The prediction development is supported by the Python programming language with a single hidden layer and two hidden layers Neural Network, as well as the traditional Multiple Linear Regression tools. The simulation results show that the two hidden layers Neural Network method has a higher level of accuracy compared to the single hidden layer and Multiple Linear Regression as seen from the value of R2, MSE, and MAE.
Study of power flow and stability for a hybrid diesel-PV power system in Indonesia
Authors: Soefian W , Azka R , Jufri F H , Aryani D R , Utomo A R
Published: November 2020

Diesel power plants are still the main choice for supplying isolated grids in Indonesia. Although this kind of power plant is easy to install, it has a high cost of energy (COE) mainly due to the cost of diesel fuel. Besides, Indonesia as a tropical country has a high intensity of solar radiation. Moreover, the investment cost of PV power plant is getting lower and it does not require high operation cost. Thus, the implementation of PV power plant is considered promising in Indonesia, and the idea of combining diesel power plants with PV in isolated grids arises to increase the efficiency of the COE. Apart from the economical aspect, the technical aspect of a hybrid diesel-PV power system implementation needs to be studied as well. In this study, the impact of the PV power plant interconnection to the existing grid is analysed in terms of the power flow and the transient stability using the DIgSILENT PowerFactory software. Furthermore, a load-sharing scheme is applied to some diesel generator units. According to the simulation result, the hybrid power system operated within the allowable voltage limits. After some transient events occurred, the hybrid power system was able to maintain its stability.
Utilization of palm kernel shell ash as stabilization materials for clay to settlement consolidation
Authors: Mariina  , Fahriani F , Apriyanti Y
Published: November 2020

Consolidation is a change in soil volume at the time of loading due to pore pressure dissipation. The consolidation parameter is a parameter that determines the consolidation process and magnitude of the settlement consolidation in soil. The process of consolidation in clay takes a long time and the settlement consolidation that occurs is relatively large, so it is necessary to improve soil stability on clay. Palm kernel shell ash is used in this research to enhance clay stability. Clay was mixed with palm kernel shell ash with varying levels of 5%, 10%, and 15% of the soil the dry weight. The Consolidation test was carried out on a mixture of clay and palm kernel shell ash to obtain consolidation parameters like the values of consolidation coefficient (Cv), compression index (Cc), and settlement of consolidation (Sc). The results of this research showed that the consolidation coefficient value increased with increasing levels of palm kernel shell ash. The Compression index and settlement of consolidation decreases with increasing levels of palm kernel shell ash. Base on the research, it can be concluded that the addition of palm shell ash to clay can accelerate the process of consolidation and reduce the value of settlement of consolidation.
Reliability analysis of the Kolong Kebintik as water resources for special economic zone in Tanjung Gunung, Pangkalan Baru District, Central Bangka Regency
Authors: Sabri F , Adriyansyah
Published: November 2020

Tanjung Gunung, Pangkalan Baru District, Central Bangka Regency is an area that is included in the Special Economic Zone. The Development of this area will have an impact on the increasing demand for water that must be provided by the management. The water resources will be supplied from Kolong Kebintik. Other than supply to the Special Economic Zone, it is also planned to supply water in Pangkalan Baru District. The water demand for Special Economic Zone is 43 l/s and water demand for the Pangkalan Baru Disctric is 48.11 l/s. So the total domestic demand is 91.11 l/s. To guarantee water in Kolong Kebintik is still available to needs of the Special Economic Zone and Pangkalan Baru District, it is necessary to analyze the reliability using standard operating rule. If want to get 100% reliability of Kolong Kebintik, then use only 22.8 l/s of the total demand 43 l/s or only 53% of the needs of the Special Economic Zone.
Important value aspect of mangrove community at coastal area of Pangkalpinang City, Bangka Island
Authors: Akhrianti I , Gustomi A
Published: November 2020

Mangrove is a one of high - level plants becouse it has structure roots, branches and leafes. Mangrove commonly was found in the delta or brakishwater, but has ecological benefit as well as economic value. Mangrove found in the intertidal zone and high tide level. This research was aimed to analysis important value aspect of species mangroves at coastal area of Pangkalpinang City. This study uses a purposive sampling method. Data was collected using the line and plot transect method (LTP) and hemisphere photography agreed upon for mangrove monitoring in the COREMAP-CTI. The results showed that Mangrove composition found in 5 stations as many as 22 species mangroves which were classified into 10 family Rhizophoraceae, Sonneratiaceae, Avicenniaceae, Meliaceae, Combretaceae, Rubiaceae, Euphorbiaceae, Myrcinaceae, Arecaceae, Malvaceae, Pteridaceae. The type of vegetation that has the highest INP value at the capling level is Rhizophora apiculata BI. of 266.65%, and The type of vegetation that has the highest INP value at the sapling level is Rhizophora apiculata BI. of 202.85%. Dominance species found in 5 station is Rhizophora apiculata BI and Sonneratia alba.
Green mining: technical study of off-shore tin mining using cutter suction dredger in Bangka Island, Indonesia
Authors: Virgiawan M R , Pitulima J
Published: November 2020

According to government regulations regarding good mining practice, PT Timah Tbk and its partners have begun to develop offshore mining techniques using Cutter Suction Dredger (CSD). Therefore there is a need for a technical study of the application of CSD in offshore tin mining. The method used in this research is to observe field activities directly. Observation of mining data of mining design, dredging system and mapping of bathymetri. The process flow, production and tin ore recovery of mineral processing. Observation of the tailings disposal considers the minimal impact on the environment. The result is mining design using CSD applies a long face system with a combination of vertical digging. The opening angle of the two anchors amounting to 90-145° produces width snee of 40-55 m. This method is capable of producing an average rate of soil removal of 250 m3/hour. The floating mineral processing plant uses a three-stage jigging method with Circullar and Pan American types plus a shaking table resulting a washing tin recovery of 66%-90%. Considering bathimetry, the geotube embankment technique can control the spread of tailings. The conclusion is that the mining process using CSD is one step better in terms of implementing good mining practice.
Effect of electrode numbers in electrocoagulation of Batik Cual wastewater: analysis on water quality and energy used
Authors: Gusa R F , Sari D N , Afriani F , Sunanda W , Tiandho Y
Published: November 2020

Batik cual is one of the leading textile products in the Bangka Belitung Islands. In their production processes resulted dye pollutan in wastewater. Most batik cual industries use synthetic dyes such as remazol brilliant blue royal which can damage the environment if discharge without further treatment. Electrocoagulation is a method that can be used as a first step in processing batik cual wastewater. In this paper, we analyze the relationship between the number of aluminium electrodes used in the electrocoagulation process and the quality of the water produced and the energy used. Wastewater quality parameters observed included pH level, number of dissolved particles, conductivity level and turbidity. Through this comparison, it can be obtained information related to the key parameters of electrocoagulation to increase its efficiency. The optimum result obtained when using six electrodes in the electrocoagulation process.
Resource Recovery Potential of Wastewater Treatment Plants in Yogyakarta
Authors: Marleni N N N , Putri K N R , Istiqomah N A
Published: November 2020

Wastewater contains water, nutrients, and energy resources, which can be recovered for human activities. Product from wastewater is one of the solutions to provide energy and food security amidst the looming energy and fertilizer crisis. Unfortunately, wastewater treatment plants in developing countries are often designed not to accommodate the concept of resource recovery. Currently, there is a real lack of feasibility analysis of upgrading existing wastewater treatment plants to accommodate the concept of resource recovery. Therefore, this study aims to determine the resource recovery potential in existing wastewater treatment plants in Yogyakarta and identify their limitations for resource recovery. Two wastewater treatment plants in Yogyakarta were assessed, one with anaerobic treatment, the other with stabilization ponds. The feasibility is assessed by the parameter of wastewater flow, organics, nutrients, and microbiology compounds. The findings of this study will be beneficial for a regional management standpoint to consider the most suitable strategy for wastewater management in Yogyakarta.
The contribution of Business Environment Factor in Forming the Entrepreneurial Characteristics of White Pepper Smallholders
Authors: Astuti R P , Bahtera N I , Atmaja E J J
Published: November 2020

Nowadays, entrepreneurship is required by white pepper smallholders to face the challenge of the change in the business environment. The study on the entrepreneurial characteristics also contributes to equipping the appropriate training program related to the psychological characteristics of smallholders. Its study has not massively being done by scholars. The study aims to identify the entrepreneurial characteristics of white pepper smallholders in Bangka Belitung Islands Province that can be formed by the influence of the business environment. The questionnaire was used as the data collection technique. Simple random sampling was employed as the sampling method. 90 white pepper smallholders were the total of respondents. Structural equation modelling analysis using smart partial least squares was applied to analyse the data. The study revealed that there was a significant factor in the business environment in shaping the entrepreneurial characteristics of white pepper smallholders. The input availability became the main factor of the business environment in affecting the entrepreneurial characteristics. It concluded that the factor of the environment contributed to form the entrepreneurial characteristics of white pepper smallholders. It suggested that the policymaker should concern about creating the proper business environment in developing the entrepreneurial characteristics of white pepper smallholders so that the number of smallholder agribusiness entrepreneurship in the province can be exponentially raised.
Measurement of sustainable development in Bangka Belitung Islands Province
Authors: Putri A K , Wulandari A , Akbar M F
Published: November 2020

In this paper, the authors present a review about sustainable development in the Bangka Belitung Islands Province in 2016-2018. In sustainable development research is described as a balance of economic, social, and environmental development. The data used is the Times Series data from year 2009 to year 2018 in Bangka Belitung province which is in the form of GDRP for constant price of 2010, Human Development Index, and environmental quality index. The results of the research showed that the development of several indicators of development has not been the construction of economic, social, and environmental development in Bangka Belitung Islands province. More development shows improvements from the economic side, while that for the social side has already shown a good figure. What needs to be a concern is the quality of the environment in the Bangka Belitung Islands province that shows that sustainable development in this province indicates the presence of pressure on the environment.
Analysis of environmental resilience index due to realization of village funds in the Bangka Belitung Islands Province
Authors: Rosalina E , Sucipto
Published: November 2020

The government has provided funds to villages. Use of that fund to develop villages status from underdeveloped become independent villages. This goal is in the strategic plan of the Republic of Indonesia from 2015-2019. Improved village status can be seen from the village index builds (IDM). IDM consists of social (IKS), economic (IKE), environmental (IKL). The IKL index is very important but is not a priority in village development. The aims of the research is to examine how much the use of village funds in the index of environmental resilience in five villages. The research in West Bangka with the status of developing villages. This research uses a mixed method. By distributing questionnaires to the community and interviews with village officials. They are some results of this study. First, from interviu the result that village do not allocated fun for improve environmental resilience. Second, the village is indeed not to divide village funds to overcome the potential/prone to natural disasters. Village officials realize that each village has the potential for natural disasters. The condition of the villages that are close to the coast. They hope next year, the government has a regulation. The questionnaire obtained from the results showed that the use of village funds for infrastructure. The use of village funds for infrastrure are bridges, irrigation, embung, and drainage. From the calculation of the scale of receiving benefits from water, soil, air pollution, landslides, and overcoming drought are above 30 percent. This implies that the community has benefited from village funds for environmental resilience.
Digital transformation to improve quality, efficiency and safety in construction of roads incorporating recycled materials
Authors: Widyatmoko I
Published: November 2020

Raw materials and supplies have been subjected to much increased pressure due to the recent boom in infrastructure construction. These activities have caused more severe environmental damage. The construction and demolition of infrastructure assets accounts for around 30 per cent of global material consumption and waste generation. There are many benefits associated with recycling end of life materials and waste from these construction works. Recycling reduces disposal costs and carbon emissions. It also helps complying with environmental legislation and restrictions on what can be sent to landfill. It is expected that reliable recycling methods in the future should make efficient use of comprehensive catalogue and databases of materials currently used in construction. Greater challenges when dealing with end of life infrastructure assets are often associated with the lack of, or incomplete, records about the materials used in the assets, such as since the design and construction phases, and throughout their serviceable lives. The increasing use of Big Data, smart sensors and automation open ways to build banks of material database into BIM (building information modelling) and other similar methods. This will provide detailed records of existing materials and their in-service history ahead of any future recycling, thus better informed during the design stage, and helps improving the effectiveness and quality of recycled products. Furthermore, road construction industry has been adopting the latest advancement in digitalization of pavement assessment technology. This new approach was aimed at obtaining substantial improvement in the productivity levels, quality and safety of the construction industry and minimizing impact on the environment. A new concept called “Construction 4.0” was subsequently introduced to implement this approach. This concept is often associated with key components such as smart automation, predictive intelligent, real-time data exchange, 4D/5D executions and immediate field-to-office stakeholder communication. These components are currently at early stages however, it has been evidenced that some of these components are being realized. This paper discusses the opportunity and potential benefits associated with the digital transformation in construction industry, specifically as means to promote quality, efficiency and safety in future recycling.
Study on simultaneous degradation of nitrogen and phosphorus in wastewater from sludge dewatering removal by mixing sodium and lanthanum modified zeolite
Authors: Zhang Chunyu , Zhou Bingling , Li Zaiguo
Published: November 2020

This paper studied the adsorption of nitrogen and phosphorus in wastewater from sludge dewatering by sodium and lanthanum modified zeolite. Under the condition of initial concentration of 50mg/L, the dosage of 7.5g/L and reaction time of 3h, the removal rate of ammonium reached 92% by sodium zeolite; while the removal rate of phosphate reached 99% by lanthanum zeolite under the condition of initial concentration of phosphorus 60mg/L, the dosage of 10g/L and reaction time of 12h. Two kinds of modified zeolite were mixed to synchronously remove nitrogen and phosphorus from wastewater from sludge dewatering. The results showed that the removal of phosphate by lanthanum zeolite was motion influenced by the concentration of ammonium in the solution, and the existence of lanthanum zeolite was useful to promote the removal of ammonium. Otherwise, sodium zeolite did not have the ability to adsorb phosphate, and the capacity of ammonium adsorption decreased with the increase of phosphate concentration in the solution. When the mass mixing ratio of sodium zeolite and lanthanum zeolite was 4:6, the removal rates of ammonia nitrogen and phosphorus reached 89.6% and 97.5% respectively.
Research on Beijing-Tianjin-Hebei ecological and environmental protection cooperative development
Authors: Nie Xiaoqin , Shu Tianchu , Guo Hanwen , Bai Binjie , Li Xu
Published: November 2020

China’s rapidly growing urbanization has brought upon setbacks such as resource depletion and environmental pollution. As an important representative of China’s economic development and urban agglomeration, the Beijing-Tianjin-Hebei Urban Agglomeration’s (BTHUA) coordinated development of eco-environmental protection is still in a lagging state, and the restoration process of eco-environmental governance is relatively slow. Based on the analysis of relevant national demographic data, this study evaluates the current status of the BTHUA’s eco-environmental protection program and the main issues it faces with respect to economic development status, pollutant discharge characteristics, related resources distribution characteristics, and technology resources sharing mechanisms. The results show that the current pollutant emissions and the distribution of scientific and technological resources in the BTHUA are both in an unbalanced state, together with the shortage of sharing mechanisms, resulting in a lower efficiency in the coordinated development of the ecological environment protection in BTHUA. Simultaneously, based on the front-end scientific research results, the corresponding countermeasures and scientific suggestions are put forward for the main bottleneck problems, to provide certain theoretical support for the coordinated development of ecological and environmental protection.
Multiple perspectives on eco-compensation of ecological migrants in the Three Rivers Headwaters Region, China
Authors: Wei Xiaoyan , Yang Xixia , Mao Xufeng , Wei Xijie
Published: November 2020

The purpose of the study is to determine the reasonable compensation standards for ecological immigrants in the Three Rivers Headwaters region, four calculation methods were proposed according to different conditions. Results show that the minimum compensation standard for herdsmen was recommended from the current 10,000 yuan/year to 25,000 yuan/year. The highest compensation standard is proposed to, with the consideration of the quality and area of grassland, be increased by 2.5-5.0 times compared to the current compensation standard. It is expected that the current study may provide a novel perspective and reference for the compensation standards for ecological immigrants for nature reserves.
Study on adsorption of lead and cadmium by non-burning ceramic granules from waterworks residual sludge
Authors: Tang Haiyun , Zhao Yuanyuan , Li Yaoyu , Liu Danni , Chen Yuehui , Xu Youze
Published: November 2020

In this experiment, the unburned ceramiste water treatment residuals (UCWTR) was prepared by the burning-free method to study its adsorption performance on Pb and Cd. Adsorption experiments show that the quality of ceramsite improved with the height of the filler layer in the reaction column, and its penetration and depletion time are prolonged. On the contrary, the driving force of mass transfer increases with the initial concentration of water in the reaction column, and the penetration and exhaustion time is shortened. The dynamic adsorption process of Pb and Cd by UCWTR is more consistent with the Thomas model and Yoon-Nelson model, and the correlation coefficient R2 is greater than 0.9. Under the condition that the initial flow rate v is 10 mL/min, the height of the packing layer h is 10 cm, and the initial concentration C0 is 150 mg/g, the fitted dynamic saturated adsorption capacities of UCWTR for lead and cadmium are 9.22 mg/g, 11.52 mg/g, the static adsorption capacity of lead and cadmium are 1.48 times and 155 times respectively. kT decreases as the height of the filler layer and the initial concentration increase; kYN decreases as the height of the filler layer increases, and increases as the initial concentration increases; the time t required to penetrate 50% of the adsorbent increases with the height of the filler layer and decreases with the increase of the initial concentration, which indicated that the solution did not reach full contact with UCWTR during the dynamic adsorption process.
Design of clean energy dispatching system for wind and solar storage
Authors: Song Jinghui , Su Leitao
Published: November 2020

In order to optimize the capacity dispatch of energy storage system in grid-connected wind-solar hybrid power generation system, a method for optimizing the capacity of hybrid energy storage system composed of supercapacitors and batteries in grid-connected wind-solar hybrid power generation system is proposed by utilizing the generation data of wind power and photovoltaic and the dispatch data of power grid. Based on the method of Particle Swarm Optimizer (PSO), it was simulated that wind-solar hybrid power joined into the dispatch according to the rules of dispatch system. The best power dispatch was achieved by multi-objective particle swarm optimization (MPSO). The results show that the accuracy of capacity optimization of energy storage system can be improved by considering both the total continuous power loss and the instantaneous power loss. The hybrid energy storage system composed of supercapacitors and batteries can improve the overall security and economy of the power grid.
Pitting corrosion of chloride ions in electrocoagulation for Cr(VI) removal: optimization by response surface methodology
Authors: Luo Yuanling , Zhang Ruiqi , Zhan Qi , Liao Xiaoxi , Hu Zhenxin , Zhao Peiling , Xu Haiyin
Published: November 2020

This work observed an interesting phenomenon of pitting corrosion by chloride ions (Cl−) in electrocoagulation (EC) for Cr(VI) removal. High Cr(VI) removal capacity was achieved by initiating pitting corrosion on iron surface with Cl− over 50 mg L−1, as showed by environmental scanning electron microscope analysis (ESEM). Then response surface methodology (RSM) was applied to optimize the Cr(VI) removal in the case of Cl−. RSM suggested that the optimal operation conditions were initial pH at 5.24, applied currents at 0.914 A and Cl− concentration at 54.37 mg L−1. The verification test showed 99.98 % of Cr(VI) removal efficiency under the above optimal condition. Our study indicated that Cl− can act as an enhancement factor by pitting corrosion in EC for Cr(VI) removal.
Numerical simulation of the environmental impact of oil spill in the Liuheng Island of Zhoushan City
Authors: Huang Yi , He Yufeng , Tang Ming , Min Xiangqiang , Sheng Yehua , Chen Peng
Published: November 2020

At present, numerical models of 2D tidal current and oil spill have been widely used in simulating the diffusion and spread of spilled oil. Thus, this paper adopts the MIKE21_FM hydrodynamic model, and establishes a 2D tidal current dynamic model based on unstructured meshes in the Liuheng Island of Zhoushan city. After verification by the measured data, it can be found that this model can reflect the hydrodynamic characteristics perfectly, and provide sufficient hydrodynamic conditions for the simulation of oil spill. Based on that, the MIKE21/3 OS model is applied for predicting the risk of oil spill. Accordingly, 8 working conditions are simulated to track the spread and sweeping area of spilled oil. The results show that both oil spill time, tidal current and wind direction can affect oil diffusion, while wind direction is the most dominant factor. Moreover, the sweeping area increases gradually with time, and the maximum area reaches 2018.95 km2 after 72 hours at ebb tide under the wind direction of WNW.
Corrosion Investigation of Sn-0.7Cu Pb-Free Solder in Open-Circuit and Polarized Conditions
Authors: Aziz Mohd Zohirul Haziq , Zainon Nasihah , Mohamad Ahmad Azmin , Nazeri Muhammad Firdaus Mohd
Published: November 2020

The corrosion performance of Sn-0.7Cu solder alloy was investigated in 1 M hydrochloride acid by means of open-circuit potential and potentiodynamic polarization techniques. In open-circuit potential measurement, the potential showed almost constant reading after achieving potential -550 mV, consistent with single dissolution peak observed in potentiodynamic polarization. This revealed single element dissolution process of Sn took place. Supporting morphological and phase analyses were done by using scanning electron microscope and X-ray diffraction. Phase analysis confirmed the corrosion product are SnO and SnO2. Morphological analysis showed two type of oxide layer formed as corrosion product, which are compact oxide layer and loose rod-like oxide layer after polarization, while rod-like corrosion product was diminished in open-circuit condition. This indicate that complete protection from further corrosion was impossible due to the incomplete passivation layer formation in potentiodynamic polarization.
Structural and dimensional analysis of LDPE/TPS blend filled with calcium carbonate
Authors: Halim Anis Adila Ab , Wahab Mohamad Kahar Ab
Published: November 2020

This study aims to investigates the changes in structural, thermal stability and water absorption properties of thermoplastic starch (TPS) before and after modification with citric acid and ascorbic acid. The first stage of study involved the preparation of TPS from native potato starch. Starch will be converted into thermoplastic like in the presence of glycerol as plasticizer. For the second stage, LDPE was blended with TPS to produce LDPE/TPS blend with and without modification. Then, the influence of calcium carbonate as particulate filler on the properties of LDPE/TPS blends was also investigated. Structural findings based on the FTIR analysis showed the formation of new ester bond on the TPS backbone after the modification, which correspond to the formation of crosslinking network in TPS phase. Water absorption test was used to determine the effectiveness of TPS modification in term of physical interaction between the phases.
The Effect of Polypropylene Grafted Maleic Anhydride on the Polypropylene / Natural Rubber Blends Filled with Cyperus Odoratus
Authors: Abidin Norfatulikmah Zainal , Wahab Mohamad Kahar Ab
Published: November 2020

A new thermoplastic blend was developed by using polypropylene (PP) with natural rubber (NR) as the base material. The natural filler is added to enhance the properties of PP/NR blend. Two series of blends under varying conditions were prepared and investigated. The first series was to compare the properties of PP/NR blend with diferent filler loading. Second is to investigate the effect of polypropylene grafted maleic anhydride (PP-MAH) on the properties of PP/NR blend filled with Cyperus Odoratus. Process development, tensile properties, thermal analysis, FTIR analysis and morphological characterization of blends were investigated with the variation of the conditions of the blend. The increasing filler loading decrease the tensile properties of the PP/NR blend as support by morphology study of the PP/NR blends. Icorporation of PP-MAH was resulted in improved tensile and thermal properties compared to uncompatibilized counterparts. The increament in tensile strength was confirmed by the SEM study that showed better dispersion of NR in the PP matrix and improved adhesion between the two phases.
Failure Analysis on U-Bend Header Tube of Boiler Economizer
Authors: Hayazi Nur Farhana , Shamsudin Shaiful Rizam , Wardan Rajaselan
Published: November 2020

A water tube boiler is a type of boiler in which water circulates in tubes heated externally by fire. It was found that the water tube economizers are often subject to the serious damage mainly because of the overheating and corrosion. Thus, the metallurgical investigation procedures starts with the visual inspection, stereomicroscopy, metallography and chemical analysis methods. It was identified that the failure of the u-bend tube was due to the cracking caused by bending forces during the procedures. This cracking causes a leak for the tube. The appearance of corrosion on the shell side is due to the presence of small content of sulphur under the boiler environment. Several welding imperfections were also detected, however, both corrosion and welding imperfections were not the primary caused of the tube failure. From the analysis, the use of SUS304 grade stainless steel was discovered to be the appropriate material selection for the tube boiler.
Preparation of a Visible light Active N-doped TiO2 Photocatalyst using Microwave Irradiation Technique
Authors: Nawawi Wan Izhan , Razak Sharin , Fazeri
Published: November 2020

The dye wastewater which directly discharges without treatment process will affect the environment. The semiconductor like titanium dioxide (TiO2) has gained attention as most potential material for photocatalysis process to treat the dye wastewater with act as photocatalyst. However, this semiconductor has their limitation toward the photodegradation under visible light irradiation. In this study, TiO2 has been modified by doping with nitrogen (N) to improve the effectiveness under visible light irradiation. This simple prepared N-doped TiO2 was prepared by mixing of TiO2 powder with urea as N precursor under microwave irradiation instead of using muffle furnace as heating media. The nitogen was chemically bonded with TiO2 as proven by XPS analysis. N-doped TiO2 sample show active under visible light irradiation due to lower band gaps energy of sample observed by UV/Vis-DRS. An active photo response under visible light was observed from N-doped TiO2 with 80 minutes time irradiation to complete the reactive red 4 (RR4) color removal, while no photocatalytic degradation was observed from unmodified TiO2 under the same irradiation.
The mixture material of dried straw and kapok for acoustic treatment for UTeM mosque
Authors: Ismail Mohd Muzafar , Razak Jeefferie Abd , Junid Ramli , Khalid NorAisah , Arith Faiz , Said Maizatul Alice Meor
Published: November 2020

The acoustical requirements in terms of intelligibility and liveliness are dissimilar for both of sounds-recitation and speech on religious subjects at UTeM mosque. To attain an overall satisfactory acoustical performance, it is significant to find an optimum Reverberation Time (RT) and the best directivity, which is the major factors affecting intelligibility and liveliness. This experiment is conduct to gauge the effect of RT by making it a variable, while keeping other factors as non-variable and fulfilling ideal conditions for maximum intelligibility. Bearing in mind, the acoustical problems always occurred in any communication building. To improve the problem, this paper presents the new idea of improvement by using biodegradable sound absorber materials which is the mixture of dried rice straw and kapok.
Assessment of Mechanical Properties of Recycled HDPE and LDPE Plastic Wastes
Authors: Murat Bibi Intan Suraya , Kamalruzaman Muhammad Syarifuddin , Azman Mohamad Hafiz Nor , Misroh Muhamad Fazlee
Published: November 2020

Most plastic materials can be recycled, and turning them into some useful products can be one of the options in reducing environmental pollutions. In this project, High Density Polyethylene (HDPE) and Low Density Polyethylene (LDPE) were used, shredded into smaller pieces and were hot-pressed to become flat plates. Both materials were then mixed with industrial waste sawdust with an aim to investigate their material properties and their suitability to be used in domestic applications such as bricks, pavement and roof tiles. Three destructive and one non-destructive methods have been conducted: tensile, impact, water absorption and ultrasonic testing. It was found that the tensile properties and impact resistance of the recycled HDPE are better than the recycled LDPE, but 10% lower than their virgin polymers. Higher stiffness and lower impact resistance were observed from specimens with additional sawdust filler in comparison to their original polymers. From the ultrasonic measurement, higher wave velocity and lower attenuation in HDPE specimens were observed, compared to the LDPE specimens, attributed by a higher modulus and density of the HDPE specimens. The ultrasonic velocity, which reflects the elastic modulus, and the attenuation that reflect the microstructure inhomogeneity are respectively decreased and increased when more fillers were added to the original specimens. This study reveals that the mechanical properties of the recycled HDPE and LDPE are closer to their virgin materials, and they have huge potential for plastic recycling.
Effect of Different Filler Loading on Flexural Properties and Water Absorption Behavior of Kenaf Core Fiber Reinforced Polypropylene Composite
Authors: Mustapa Nur Rusyidah , Rozyanty A. R. , Pisal Mohd Hanif Mohd
Published: November 2020

In this investigation, kenaf core fiber (KCF) reinforced polypropylene (PP) composite was prepared via extrusion and compression moulding. The effect of different ratio of KCF filler with PP on flexural properties of composite had been investigated. PP and KCF filler were prepared with different filler loading of 5, 10, 15, 20 and 25 wt% using twin-screw extruder at temperature 180 ºC and rotor speed of 70 rpm, followed by compression moulding at the same temperature. The flexural tests were conducted to evaluate the flexural properties of the composite. The results obtained showed that the incorporation of KCF in PP increased the flexural strength and flexural modulus of the composite. The water absorption behaviour of the composite was also investigated. It was found that water absorption of composites increased with increasing of fiber content.
Review on the effect of Gallium in solder alloy
Authors: Ervina Efzan M.N , Nur Faziera M.N
Published: November 2020

Soldering is a well-known metallurgical joining method that uses a filler metal, the solder, with a melting point below 425°C. The trends toward to miniaturization in microelectronic packaging industries have motivated the development of high performance lead-free solders. However, the properties of the lead free solder cannot match the properties of lead solder. To overcome this problem, a dopant is added to the based lead free solder. In this paper, review on the effect of Gallium as doped was discussed.
Accessible dynamic micropatterns in monolayer cultures via modified desktop xurography
Authors: Tran Raymond , Hoesli Corinne A , Moraes Christopher
Published: November 2020

Micropatterned cell cultures provide an important tool to understand dynamic biological processes, but often require specialized equipment and expertise. Here we present subtractive bioscribing (SuBscribing), a readily accessible and inexpensive technique to generate dynamic micropatterns in biomaterial monolayers on-the-fly. We first describe our modifications to a commercially available desktop xurographer and demonstrate the utility and limits of this system in creating micropatterned cultures by mechanically scribing patterns into a brittle, non-adhesive biomaterial layer. Patterns are sufficiently small to influence cell morphology and orientation and can be extended to pattern large areas with complex reproducible shapes. We also demonstrate the use of this system as a dynamic patterning tool for cocultures. Finally, we use this technique to explore and improve upon the well-established epithelial scratch assay, and demonstrate that robotic control of the scratching tool can be used to create custom-shaped wounds in epithelial monolayers, and that the scribing direction leaves trace remnants of matrix molecules that may significantly affect conventional implementations of this common assay.
Origin of the complex Raman tensor elements in single-layer triclinic ReSe2
Authors: Resende Geovani C , Ribeiro Guilherme A S , Silveira Orlando J , Lemos Jessica S , Brant Juliana C , Rhodes Daniel , Balicas Luis , Terrones Mauricio , Mazzoni Mario S C , Fantini Cristiano , Carvalho Bruno R , Pimenta Marcos A
Published: November 2020

Low symmetry 2D materials offer an alternative for the fabrication of optoelectronic devices which are sensitive to light polarization. The investigation of electron–phonon interactions in these materials is essential since they affect the electrical conductivity. Raman scattering probes light–matter and electron–phonon interactions, and their anisotropies are described by the Raman tensor. The tensor elements can have complex values, but the origin of this behavior in 2D materials is not yet well established. In this work, we studied a single-layer triclinic ReSe2 by angle-dependent polarized Raman spectroscopy. The obtained values of the Raman tensor elements for each mode can be understood by considering a new coordinate system, which determines the physical origin of the complex nature of the Raman tensor elements. Our results are explained in terms of anisotropy of the electron–phonon coupling relevant to the engineering of new optoelectronic devices based on low-symmetry 2D materials.
Influence of helium ion irradiation on the morphology and microstructure of CN-G01 beryllium
Authors: Luo Xiaofang , Gong Baoping , Wang Long , Cui Minghuan , Feng Yongjin
Published: November 2020

Beryllium is considered as a candidate of ITER first-wall (FW) armor and neutron multiplier in fusion reactors. To assess the irradiation resistance of CN-G01 beryllium, which has been accepted as an alternative ITER-grade beryllium in China, 180 keV helium ions with fluences of 1.0 × 1017 ions cm−2, 5.0 × 1017 ions cm−2 and 1.0 × 1018 ions cm−2 were implanted at room temperature. The theoretical simulation of energy loss, damage distribution and helium concentration were proceeded by SRIM. In this paper, we report the experimental exploration of ion fluence effect on surface morphology and microstructure of irradiated samples. Field Emission Scanning Electron Microscope (FESEM) analysis depicted the formation and growth of helium bubbles at different irradiation ion fluences. No obvious exfoliation or cavities was observed on the surface at all ion fluences, suggesting a reliable radiation resistance of CN-G01 beryllium. Atomic force microscopy (AFM) morphology showed that the maximum height of bubbles was 47.8 nm. Surface roughness values increased slightly due to the formation of defects and bubbles on the irradiated beryllium surface. Nevertheless, the structural analysis demonstrated by grazing incidence x-ray diffraction (GIXRD), indicated an obvious preferred orientation on (101) peak at various ion fluences. Annihilation of defects caused by a small rise of the localized temperature could explain the increasing intensity of diffraction peak (101).
Turbulent boundary layer control with a spanwise array of DBD plasma actuators
Authors: LI Yueqiang , GAO Chao , WU Bin , WANG Yushuai , ZHENG Haibo , XUE Ming , WANG Yuling
Published: November 2020

The turbulent boundary layer control on NACA 0012 airfoil with Mach number ranging from 0.3 to 0.5 by a spanwise array of dielectric barrier discharge (DBD) plasma actuators by hot-film sensor technology is investigated. Due to temperature change mainly caused through heat produced along with plasma will lead to measurement error of shear stress measured by hot-film sensor, the correction method that takes account of the change measured by another sensor is used and works well. In order to achieve the value of shear stress change, we combine computational fluid dynamics computation with experiment to calibrate the hot-film sensor. To test the stability of the hot-film sensor, seven repeated measurements of shear stress at Ma = 0.3 are conducted and show that confidence interval of hot-film sensor measurement is from −0.18 to 0.18 Pa and the root mean square is 0.11 Pa giving a relative error 0.5% over all Mach numbers in this experiment. The research on the turbulent boundary layer control with DBD plasma actuators demonstrates that the control makes shear stress increase by about 6% over the three Mach numbers, which is thought to be reliable through comparing it with the relative error 0.5%, and the value is hardly affected by burst frequency and excitation voltage.