bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of Fe content on crystal phase and mechanical properties of 6061 aluminium alloy
Authors: Wang Zhen , Jiang Shiwen , Liu Tianze , Ban Chunyan
Published: August 2023

In order to eliminate the adverse effects of impurity element Fe in aluminium alloy, the effects of Fe content on the microstructures and mechanical properties of 6061 aluminium alloy were studied utilizing scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and tensile testing machine. The results show that Fe exists mainly in α-AlFeSi and β-AlFeSi phases. Elemental Fe promotes the generation of fishbone shaped α-AlFeSi phase, while the percentage of needle shaped β-AlFeSi phase gradually decreases. After homogenizing annealing, the Mg2Si phase has been redissolved, and a large amount of Si element exists in the aluminium matrix. With the increase of Fe and Si content, β→α phase transition has been completed, and the fishbone α-AlFeSi phase accumulates at the grain boundary. After the extrusion forming process, the morphology of the α-Al12(MnFe)3Si phase changes from fishbone to granular, and the bulk deposition of α-Al12(MnFe)3Si improves the strength of 6061 aluminium alloy.
Precipitation Behavior of Al3(Sc, Zr) Particles in Al-Mg-Zn Alloy during Two-stage Homogenization
Authors: Zhang Tianyou , Yan Lizhen , Zhang Yongan , Xiong Baiqing , Xiao Wei
Published: August 2023

The precipitation of secondary Al3(Sc, Zr) particles in Al-Mg-Zn-Sc-Zr alloy during the two-stage homogenization has been studied by OM, SEM, and TEM. The results indicated that Al3(Sc, Zr) particles grew gradually with the first-stage homogenization temperature ranging from 380°C to 440°C. The first-stage homogenization temperature greatly affected the particle size of Al3(Sc, Zr). The lower the first-stage homogenization temperature was, the smaller the particle size of Al3(Sc, Zr) was. After the same second-stage homogenization treatment, the particles were coarsened, and the size was 15.2 nm, 15.9 nm, and 19.7 nm, respectively. Meanwhile, the Al3(Sc, Zr) particles exhibited a legume-like morphology and maintained a coherent relationship with the Al matrix after different homogenization treatments.
Microstructure and Properties of Mg-Zn-Ca Alloy by Using Different Types of Cladding ECAP
Authors: Jiang Shiwen , Wang Zhen , Liu Tianze , Ban Chunyan
Published: August 2023

A self-made 120° die was used for ECAP, and the effect of using different types of metal cladding and different temperatures for ECAP on the microstructure and mechanical properties of Mg-5Zn-0.6Ca alloy was analyzed. Microstructure observation and tensile testing were also carried out. The results show that, after ECAP, the grain size of the magnesium alloy was greatly refined, and the mechanical properties were significantly improved. Regarding the degree of grain refinement and the improvement of mechanical properties, 6061 aluminum alloy cladding is better than the pure copper cladding.
Preparation and Characterization of Zn-doped CuAlO2 Thin Films
Authors: Liu Yantao , Wang Ying , Ma Jianping
Published: August 2023

In this paper, the CuAl1-xZnxO2 (x=0, 0.03, 0.05, 0.07, 0.1) targets have been obtained by the solid phase reaction method using analytically pure Cu2O, Al2O3, and ZnO powders as experimental raw materials, and CuAl1-xZnxO2 thin films have been prepared on quartz glass substrates by magnetron sputtering. The characteristics of CuAl1-xZnxO2 thin films have been studied systematically. The results showed that Zn doping makes the (101) and (104) diffraction peaks of CuAlO2 shift. EDS results confirmed that Zn atoms replaced Al atoms. The average transmittance could reach 57.7% at 3%, and the band gap increased as the Zn doping concentration increased and could reach 3.83 eV at 10%.
The Tribological Mechanism of Chromium at Extreme Stress-temperature Conditions Simulating the Interior Ballistic Environment in Artillery Barrels
Authors: Hu Chenchen , Xu Xu
Published: August 2023

The tribological mechanism of bulk chromium materials has been investigated at high-temperature and high-stress conditions simulating the interior ballistic environment in gun barrels. The results show a higher level of weight change after testing at 1, 000 °C as compared to that at 600 °C. The topographical difference is more evident in the friction surface after testing at 1, 000 °C than that at 600 °C. The detailed analysis of surface morphology and chemistry indicates a tribological mechanism combining oxidative wear, abrasive wear, and adhesive wear at a testing temperature of 600 °C, whilst the tribological mechanism is combined with adhesive wear and oxidative wear at a testing temperature of 1, 000 °C.
Experimental Study on Reducing Water Absorption of Foamed Light Soil by Microbial Technology
Authors: Wu Qifeng , Wang Zhengtong , Ma Rong
Published: August 2023

There is a problem with water absorption and increased density when foamed light soil is applied below the underground water level. It is necessary to study how to reduce the water absorption of foamed light soil. The microbial-induced calcite precipitation technology was used to treat the foamed light soil to reduce water absorption. The spraying and soaking methods were used for treatment, and a control group without any treatment was set up. The water absorption test was used to verify the treatment effect. The experimental results show that the water absorption of foamed light soil increases with the density and water ratio increase. It effectively reduces the water absorption of foamed light soil by microbial-induced calcite precipitation technology. The soaking method has a better effect, but the spraying method is more operable in practical engineering.
Carburizing Rate of Pyrolysis Furnace Tube in Long-term Service
Authors: Du Chenyang , Liu Chang , Li Xiaowei , Song Ce , Lu Jianyu
Published: August 2023

The high-temperature working environment of ethylene pyrolysis furnace tubes makes carburization one of the main damage mechanisms, and carburization also leads to the degradation of tube material properties and failure. It is important to study the carburization rate of long-term service furnace tubes for the evaluation of long-cycle use and carburization detection. In this paper, the relationship between carburization rate and carburization time is studied by low-pressure vacuum carburization of Cr35Ni45Nb alloy tubes with different service life (new tubes, two years, three years, and six years) in the field, aiming to provide a scientific basis for the remaining life prediction and carburization inspection for the tube material.
Mechanical Properties and Forming Quality of PLA Based on Computer 3D Printing Parameters
Authors: Meng Fanrong , Cui Haijun , Wang Meng
Published: August 2023

At present, human beings have successfully manufactured many products by using the 3D printing (hereinafter referred to as 3DP) technology, which has been widely used in many disciplines, including aerospace, national defense, biomedicine, medicine, and other fields. Therefore, 3DP has gradually attracted the attention of countries all over the world. FDM is one of the most widely used 3DP technologies, which has the characteristics of simple operation, small forming equipment, and easy placement. Printing technologies and printing materials are two main factors affecting the quality of 3DP products. At present, there are three kinds of plastics for the 3DP technology, namely ABS, PLA, and PA. Among them, PLA has the advantages of degradability and no pungent smell, which has been widely used in 3DP. Therefore, this paper analyzes the influence of 3DP product parameters on mechanical properties based on PLA materials. At the same time, there are still many problems with surface roughness and dimensional accuracy of FDM processing, which is also the main problem hindering 3DP. Therefore, it is of great significance to study the mechanical properties and forming quality of PLA based on 3DP parameters.
Grain refinement and mechanical property of Al-Cu-Mg-Si-Ti-Sc alloy in the state of deformation treatment condition
Authors: Gao Ying , Zhao Yuhang , Yang Ning , Gao Guimei , Li Shichun , Liu Darui
Published: August 2023

Al-Cu-Mg-Si-Ti-Sc compound metal with distinct content of Sc increment was prepared by using metallurgical engineering processing. The formation of Sc in Al-4.5%Cu-1.3%Mg-0.6%Si-0.2%Ti-xSc compound metal and its microstructural observation was studied with SEM. The mechanical performances of the compound metal were measured by tensile and fatigue tests in the state of machining distortion conditions. The result reveals that the increment of 0.2% rare earth Sc can fine Al-Cu-Mg-Si-Ti-Sc compound metal grain crystals, which enhances ordinary temperature tensile strength, yield strength, and elongation. The low cycle fatigue of Al-5.2Mg-0.8Si-0.25Cr-0.1Zr-0.2Sc compound metal reveals a cyclic steady state, which mainly relies on the amplitude of the density of movable dislocations and gross applied strain during cyclic distortion. Meanwhile, under external action, the dislocation slip is more in-homogeneous, and materials are more prone to trans-granular crack in which grain crystals can coordinate distortion.
Study on the effect of Cu addition on fatigue crack growth behavior of high-strength Al-1.2Mg-1.2Si alloy
Authors: Zhang Xu , Yan Hongwei , Li Zhihui , Yan Lizhen , Gao Guanjun
Published: August 2023

This work investigated effect of Cu addition on fatigue crack growth rate and fatigue fracture morphology of Al-1.2Mg-1.2Si alloy by fatigue test machine and Scanning Electron Microscope. It revealed that effect of Cu on the fatigue crack growth rate of these alloys was related to Cu content. When the Cu content was 0.18, there did no significant influence on fatigue crack growth ability. But when Cu addition was raised to 0.37, the fatigue cracks growth resistance was significantly reduced. However, Cu addition did not significantly affect the fatigue fracture mode of the alloys. The ductile fracture was main fracture mode on this alloy.
Evaporation of nanofluid with induced bubbles under sun illumination
Authors: Yuan Bo , Zhu Qunzhi
Published: August 2023

Recently, various nanofluids have been explored to facilitate vapor production, showing the great efficacy of such fluids in solar evaporation. Plasmonic nanofluid generally requires high concentrations or mixing of individual nanofluids to achieve efficient evaporation. In contrast, carbon-based nanofluid, by its very nature, can achieve broad-spectrum absorption and require only very low concentrations. In this work, we introduce air bubbles within the carbon-based nanofluid to facilitate vapor evaporation. The dynamic bubbles effectively extend the incident light path and provide a large gas-liquid interface for moisture trapping, and the kinetic energy of the vapor generated during bubble bursting improves vapor diffusion. The coupling effect between the carbon-based nanofluid and the bubble resulted in a vapor production rate of 0.831 kg/(m2·h), with evaporation efficiencies three times that of pure water at a stable irradiance of approximately 750 W/m2, showing that both the nanofluid and bubbles play their positive roles in promoting evaporation. This work combines bubbling with evaporation systems, providing new insights into the use of solar evaporation
Preforming based on CF/PEKK prepreg continuous pultrusion process
Authors: Liu Yu , Qi Junwei , Shi Jiaqi , Cheng Zhitong
Published: August 2023

Prepreg material is continuously bent and transformed on a Preformed mold, ultimately transitioning from a flat shape to a hat-shaped long beam cross-sectional shape as it enters the hot pressing mold. This process involves various factors such as the inherent properties of the prepreg material, the control of process parameters such as pressure and temperature, and geometric characteristics, all of which can affect the outcome. Inappropriate parameters may lead to defects such as wrinkling in the prepreg layers during the preforming process, which cannot be eliminated in subsequent hot pressing processes. Therefore, it is necessary to analyze the inducing factors that cause defects (wrinkles) in the prepreg layers during the preforming stage and to explore the optimal preforming method, enabling the prepreg layers to enter the hot pressing mold in an ideal hat-shaped form. This is of paramount importance for improving the quality of precast concrete, enhancing product stability, and increasing production efficiency.
CF/PEKK advanced pultrusion thermoforming process temperature field simulation
Authors: Jin Jianghai , Wang Yuequan , Shi Jiaqi , Liu Yu
Published: August 2023

Advanced pultrusion molding technology is one of the composite molding processes. It has unique advantages in the automated manufacturing of long trusses and long beam components. Thermoplastic composites are becoming popular for research in many fields such as aerospace because of their room-temperature storage and secondary use. Since the temperature history is critical to the molding quality of thermoplastic composites, the temperature field variation of CF/PEKK composites in the advanced pultrusion thermoforming process has been explored in the context of studying the advanced pultrusion molding process of thermoplastic composites in this paper. By constructing a 3D model of the temperature field and setting up a complete solution scheme in ANSYS simulation software, the simulated temperature field data were obtained, and a real-time temperature monitoring platform was set up to obtain the measured temperature data, and the comparison showed that the two temperature profiles fit well, which proved the applicability of the model and solution scheme to this study.
Influence of different magnetic configurations on plasma parameters in SPIDER device
Authors: Zagórski R. , Candeloro V. , Sartori E. , Serianni G.
Published: August 2023

The ITER fusion reactor will be heated by fast neutral beams generated by accelerating and
neutralizing negative ions, produced in a RF inductively-coupled plasma which expands through a
region featuring a magnetic filter. During the current shut down of the SPIDER device (until 2023)
some modifications of the device have been planned to improve the system performance. These
modifications are based on the experience gained during operation of SPIDER in previous years and
include, among others, the addition of further sets of permanent magnets in the expansion chamber
of the plasma source and around the RF drivers. The purpose of these modifications is to improve
plasma confinement, and thus increase its density and homogeneity. The present paper reports the
results of numerical studies of the plasma parameters in SPIDER source with different types of
modifications of SPIDER device including new permanent magnets configurations. Analysis are done
by means of the numerical code FSFS2D in which a self-consistent two-dimensional fluid description
of the source is implemented. In order to partially account for the 3D flow pattern within our 2D
model, simulations are run in two different layouts, in the vertical plane with the magnetic
filter being perpendicular to the integration domain and in the horizontal plane with the filter
field in the integration surface. Simulation results indicate, that the permanent magnets around
the RF driver tends to increase the plasma density in the driver.
Skipper-CCD sensors for the Oscura experiment: requirements and preliminary tests
Authors: Cervantes-Vergara Brenda A. , Perez Santiago , Estrada Juan , Botti Ana , Chavez Claudio R. , Chierchie Fernando , Saffold Nathan , Aguilar-Arevalo Alexis , Alcalde-Bessia Fabricio , Avalos Nicolás , Baez Oscar , Baxter Daniel , Bertou Xavier , Bonifazi Carla , Cancelo Gustavo , Castelló-Mor Nuria , Chavarria Alvaro E. , De Egea Juan Manuel , D'Olivo Juan Carlos , Dreyer Cyrus , Drlica-Wagner Alex , Essig Rouven , Estrada Ezequiel , Etzion Erez , Grylls Paul , Fernandez-Moroni Guillermo , Fernández-Serra Marivi , Ferreyra Santiago , Holland Stephen , Lantero Barreda Agustín , Lathrop Andrew , Lawson Ian , Loer Ben , Luoma Steffon , Marrufo Villalpando Edgar , Martinez Montero Mauricio , McGuire Kellie , Molina Jorge , Munagavalasa Sravan , Norcini Danielle , Piers Alexander , Privitera Paolo , Rodrigues Dario , Saldanha Richard , Singal Aman , Smida Radomir , Sofo-Haro Miguel , Stalder Diego , Stefanazzi Leandro , Tiffenberg Javier , Traina Michelangelo , Uemura Sho , Ventura Pedro , Vilar Cortabitarte Rocío , Yajur Rachana
Published: August 2023

Oscura is a proposed multi-kg skipper-CCD experiment designed for a dark matter (DM) direct detection search that will reach unprecedented sensitivity to sub-GeV DM-electron interactions with its 10 kg detector array. Oscura is planning to operate at SNOLAB with 2070 m overburden, and aims to reach a background goal of less than one event in each electron bin in the 2–10 electron ionization-signal region for the full 30 kg-year exposure, with a radiation background rate of 0.01 dru.[1 dru (differential rate unit) corresponds to 1 event/kg/day/keV.] In order to achieve this goal, Oscura must address each potential source of background events, including instrumental backgrounds. In this work, we discuss the main instrumental background sources and the strategy to control them, establishing a set of constraints on the sensors' performance parameters. We present results from the tests of the first fabricated Oscura prototype sensors, evaluate their performance in the context of the established constraints and estimate the Oscura instrumental background based on these results.
Overcoming the Fluctuating Curve from PV Power Generation by Modelling the Integration of Hydrogen Energy Storage Into Electricity Microgrid
Authors: Sesotyo Priyo A. , Dalimi Rinaldy
Published: August 2023

Java Madura Bali (Jamali) system is the Indonesian largest grid, which contributes approximately 61%, with the Coal Thermal dominates by 59% and followed by the New Renewable Energy (NRE) of 9%. Solar Photovoltaic Power Plants (SPP) contribute only 1% from the NRE itself. Low voltage customers (TR) are approximately 61% with the residential contribute approximately 42%. The rates of the national SAIDI is 12.72 hours/subscriber/year and the national SAIFI is 9.25 times per subscriber/year. There is some challenge in regulating voltage in area with high penetration of solar PV, case of voltage fluctuation in response to the fluctuating of solar irradiance, as well as other factors such as load transient. This voltage fluctuation is proportional to the amount of current generated by the PV system and also proportional to the solar irradiance.

Hydrogen energy storage (HES) is an alternative to NRE-based energy storage technology. Integrating solar PV with hydrogen energy storage and optimisation device may mitigate PV-driven voltage fluctuation, preventing excessive reserve power flow on the grid. The hydrogen energy storage system can cover variation of the loads at the nearby solar PV system in the microgrid and the ability to manage those loads, as mentioned in the energy management system. Integrating the HES within Solar PV system can improve the curve shape, improve system reliability and voltage stability, especially in the Residential Microgrid. Also may build the opportunities to earn new revenues from wholesale electricity markets, enhancing the reliability rate and competitive monetary value.
Maximum Demand Reduction (MDRed) modelling using MATLAB Stateflow®
Authors: Subramani Gopinath , Ramachandaramurthy Vigna K.
Published: August 2023

Based on renewable energy case studies, the MDRed (Maximum Demand Reduction) Model is created as an optimization apparatus for the solar PV-battery system. In this paper, MATLAB modeling toolbox is used for simulation of the solar PV-BESS design and verification of the MDRed modeling via variations in MD limit and solar PV load. Based on MDRed model, the maximum demand supervisory control algorithm is developed via MATLAB Stateflow® for the battery management system (BMS) to monitor and regulate the load to maintain the net load consumption below MD limit with the solar PV system. In summary, the simulation with the master MD controller shows the effectiveness of the proposed controller on the BMS to cater to MD reductions during solar irradiance and load pattern variations.
Reflection & Outcome Projection on the Impact of ASEAN Energy Transition to Regional Cohesivity
Authors: Araisya Tristan Noa , Debora  , Susila Akbar Yudha
Published: August 2023

Within the past decades, the world is combating climate change that leads to the need for clean energy. In consideration of the previous notion, ASEAN has become one of the important actors in supporting the process of achieving clean energy in Southeast Asia. On the other hand, each of the countries has different potential for every type of renewable energy. That being said, Southeast Asia’s transition to clean energy has a consequential impact on the cohesivity of the region. We use neoliberal theses, specifically the green economy, to explain this. In this paper, we argue that optimistically, clean energy will bring positive impact towards regional cohesion in economics and policy terms. The cohesion itself is the result of the stepping up of ASEAN’s clean energy cooperation and the growth of intra-regional trade in that respective area. Aside from that, institutionalists also argue that institutions—in this case ASEAN—may change the state’s behavior. Nevertheless, there are few things to note if ASEAN sought to accelerate their energy transition: national interest, the involvement of great powers, the inequality in technology distribution, and the overshadowment in global investment to China, India, and Brazil due to their potential.
The Challenges of Nuclear Power Plant Development in Indonesia: A Case of Thorium Power Plant in Bangka Island, Indonesia
Authors: Kurniawan Nanang Indra , Hasanah Mahesti , Pamungkas Warih Aji
Published: August 2023

This paper discusses the challenges of nuclear power plant development in Indonesia. With a growing belief among policymakers that nuclear power could play a vital role in energy transition and diversification, it is important to analyse the process of nuclear decision-making. Drawing on the case of the development of the Thorium Molten Salt Reactor (TMSR) in Bangka Island, this paper aims to understand the social, political, and institutional aspects of thorium power plant development. More specifically, this paper elaborates on public acceptance and the regulatory environment of nuclear power development. This paper is mainly based on secondary data such as official reports, online media, and relevant academic research. We argue that nuclear power development requires not only good technological and risk management capacity but also strong public trust in the government and nuclear industry through information transparency and openness.
Size fractionated ambient particles down to nanoparticles (PM0.1) during a haze episode in Myanmar
Authors: Tial Mai Kai Suan , Amin Muhammand , Putri Rahmi Mulia , Hata Mitsuhiko , Furuuchi Masami , Phairuang Worradorn
Published: August 2023

This is the first report on the size-fractionated airborne particles small to nanoparticles (PM0.1) in Myanmar. The ambient air monitoring using a cascade air sampler of PM10/2.5/1.0/0.5/0.1 stages was done in Tachileik, Myanmar, during the dry season in 2022. Concentrations of PM2.5 and PM10 seriously exceeded air quality standards, e.g., those by the World Health Organization (WHO). The PM0.1 concentration ranged from 5.4 to 20.8 μg/m3, with an average of 13.1 ± 4.3 μg/m3, similar to other large cities in this area as Bangkok in Thailand. This result will provide air quality information in Myanmar, which will likely be the clean air act and the transition to sustainable air quality management in Myanmar and other developing countries.
Decarbonization Program through an Implementation of 411 kWp OFFGRID PV Rooftop in reducing GHG in Muara Karang Combined Cycle Power Plant
Authors: Hutajulu D S , Revina T , Dermawan M D
Published: August 2023

The Indonesian government commits to reducing greenhouse gas emissions by following the Paris Agreement to the Nations Framework Convention on Climate Change. Indonesia targets to reduce GHG emissions by 29% by 2030 with business as usual and 40% with international assistance. PT PJB Muara Karang in Jakarta has operated PV Rooftop with a total capacity of 411 kWp which is one of the renewable energy sources. The solar plants have been installed on the roof of an office building aimed at own-used. Calculation of the reduction of greenhouse gas emissions uses the reference CDM AMS I.D Version 18.0. By using this method, the reduction in greenhouse gases was approximately 158,93 ton CO2 from January 2021 to June 2022. This program can generate 411,839.7 kWh of Electricity. As a solution to reduce coal-fired power plants, in the long term, the company (PT PJB) has a target of developing New Renewable Energy of 3394 MW by 2030. The rooftop PV installation program for own use is one of the company’s commitments to reduce greenhouse gases and support the achievement of the targets energy mix for renewable energy. This program is expected to be claimed as a form of decarbonization program.
Determination of Particulate Matters and Total Suspended Particles emitted from Incense Burning
Authors: Chy Sopannha , Aun Srean , Hang Leakhena , Amin Muhammad , Hata Mitsuhiko , Or Chanmoly , Kong Sela , Taing Chanreaksmey , Um Dalin , Furuuchi Masami
Published: August 2023

Incense burning is an important ceremonial ritual in Buddhism. It is well recognized that incense smoke has negative health effects, which may be caused by the emission of submicron particles, including ultrafine and nanoparticles. Hence, in this study, the concentration of particulate matter (PM) and total suspended particles (TSP) emitted from incense burning were determined from 4 incense stick brands. The experiment was conducted in a room with a volume of approximately 146m3 using two instruments: an HV sampler and a Nano Sampler. The highest TSPs concentration from long sticks and short sticks were S1 (319.03 μg/m3) and N2 (439.75 μg/m3), respectively. High mass concentration was found in the ultrafine particle range for S2 (112.27 μg/m3) and N2 (117.30 μg/m3). In contrast, S1 and N1 exhibited high concentrations in the coarse particle mode at 79.28 μg/m3 and 86.75 μg/m3, respectively. Out of the 4 incense brands, N2 appeared to have the highest concentration in almost every particle range compared to the other 3 brands. Incense should be burned in a well-ventilated setting and try not to stay in the same place as the altar to reduce the risk of incense smoke exposure.
Monitoring Particulate Matters and Total Suspended Particles Along the Roadside and Public Area in Phnom Penh
Authors: Ngoun Pengsreng , Aun Srean , Amin Muhammad , Hang Leakhena , Hata Mitsuhiko , Taing Chanreaksmey , Kong Sela , Or Chanmoly , Um Dalin , Furuuchi Masami
Published: August 2023

This study aims to investigate the Total Suspended Particles (TSP) and Particulate Matter (PM) of the exposed area of vehicles emission along a boulevard (Russian Federation Boulevard/RFB) and public park (Wat Phnom Historical Park/WP) in Phnom Penh as a beneficial fact for passengers and tourists of air quality that they breathed in. This present study was carried out in 8 hours per sampling, twice a month, and 2 months long (March and April) of 2022 by using a high-volume sampler (HV, Shibata 500V) to determine TSP and Modified Nano-sampler (NS) to define PM (TSP/PM10/PM2.5/PM1/PM0.1). Conforming to the results, the highest percentage of relative humidity found during the sampling was when it rained (97.30%) and in the morning. Meanwhile, the lowest relative humidity was only about 48.70% which was during the hot afternoon. Additionally, TSP of RFB peak’s data was accounted as 234.04 μg/m3 which is beneath the standard of Royal Government of Cambodia (RGC), 330 μg/m3. Nevertheless, the climax concentration of fine and ultrafine particles (PM2.5 and PM0.1) that wandered in the same area had surprisingly stood in an immensely high number as 95.56 and 38.04 μg/m3. To summarize, low level of TSP in the ambient atmosphere is not correlating to less pollution since the acquired results of PM2.5 and PM0.1 had detected in a dominant level that disturb the public health respiratory system. Same thing happened to WP which is a tree-based site as well.
Carbonaceous component of Total Suspended Particulate (TSP) in Makassar City, Sulawesi Island, Indonesia
Authors: Amin Muhammad , Ramadhani Andi Annisa Tenri , Zakaria Rasdiana , Hanami Zarah Arwieny , Putri Rahmi Mulia , Torabi Sayed Esmatullah , Phairuang Worradorn , Hata Mitsuhiko , Masami Furuuchi
Published: August 2023

As the initial study related to carbonaceous components in Sulawesi Island, Indonesia, total suspended particulate matter (TSP) was collected in the roadside environments in Makassar city, Indonesia. The mean TSP level in this study was higher than the National Ambient Air Quality Standard (NAAQS) of Indonesia and much higher than World Health Organization (WHO) standards. It ranged from 21.6 to 838.6 μg/m3. The lowest concentration was found during the rainy days in paved site. The highest TSP level in all sites was found in the rush morning and late noon hour. It is related to the movement of the citizens during those periods of time. Regardless of the sites and times of sampling, organic carbon (OC) is the main fraction of total carbon (TC) for around 62.2 – 84.0%. OC and EC had well correlation indicating both carbonaceous components were emitted from the common sources. It might be emitted from the traffic emission as seen from the greater correlation between TSP and soot-EC than between TSP vs. char-EC. Hence, exhaust emissions from traffic and non-exhaust emission during the movement of vehicles should be the two main sources of TSP and its carbon components in the roadside environment of Makassar city, Sulawesi Island, Indonesia.
Preliminary discussion about the air pollution status in Afghanistan from Aerosol Optical Depth
Authors: Torabi Sayed Esmatullah , Amin Muhammad , Phairuang Worradorn , Hata Mitsuhiko , Furuuchi Masami
Published: August 2023

Kabul city, the capital of Afghanistan, has suffered from poor air quality for the last two decades. This study focuses on Kabul’s spatiotemporal characteristics of aerosol optical depth (AOD). The annual and long-term 20 years of AOD data were retrieved from Moderate Resolution Imaging Spectroradiometer (MODIS) a combination of Terra and Aqua satellites using the Google Earth Engine geospatial analysis platform to determine seasonal variation and long-term trend of the aerosols. The air mass backward trajectories were calculated using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Furthermore, ArcGIS 10.7.1 is used to visualize the AOD over the city. The results show high AOD in summer. However, autumn is recorded as the lowest average AOD season. In addition, the 20 years of data from 2001 to 2021 shows a slight increase in AOD. We suggest that the increase in AOD in the city is due to the rapid growth of the population. The cross-boundary atmospheric aerosols affect the air quality in the city.
Is Ground Source Heat Pump the Future of Space Cooling in Southeast Asia?
Authors: Widiatmojo Arif , Uchida Youhei
Published: August 2023

The rapid economic growth of Southeast Asian countries is followed by accelerated population and energy demand growth. On the other hand, the region still relies heavily on fossil fuels as the primary source of electricity. As a result, there is a growing concern about future regional energy sustainability. Space cooling has become one of the fastest-growing energy sectors. Introducing a new space cooling technology capable of providing a higher thermal efficiency can be an alternative solution. The Ground Source Heat Pump (GSHP) is a proven technology to reduce the required energy for space cooling and heating in four-season countries. However, its performance in the tropical climate is still questionable. This paper describes the challenges of GSHP application in tropical climates, such as in Southeast Asia. The research conducted to investigate the suitability of GSHP system application in Southeast Asia is also discussed. While more data are being gathered from several GSHP pilot tests in Vietnam and Thailand, the short to medium-term performance data analysis shows its advantages over the conventional Air Source Heat Pump (ASHP) or standard air conditioner. However, extensive research is still required to evaluate its long-term performance and the financial advantages over the ASHP.
Tracking Potential Renewable Energy Jobs in ASEAN
Authors: Bilqis Amira , Demoral Alnie , Rosalia Silvira Ayu , Yurnaidi Zulfikar , Safrina Rika , Yuniarni Diah Retno
Published: August 2023

Job creation in renewable is among the most significant social impacts of higher renewable penetration to the energy mix, but it also poses a challenge for countries to adapt to the changing work landscape amidst the energy transition. Hence mapping the distribution and projecting renewable employment in the coming years in ASEAN will be crucial as it would support the policy ramifications, job market, and economy. This research adopted data and scenarios trajectory from the 7th ASEAN Energy Outlook (AEO7) from 2020 up to 2050 with four technologies: Solar PV Utility-Scale, Onshore Wind, Hydropower Dam, and Geothermal. It is limited to three job types: manufacturing, construction, installation, and operation and maintenance. The data was processed using Low Emissions Analysis Platform (LEAP) software. The findings indicate that ASEAN’s renewable energy (RE) jobs will reach between 3.9 – 5.5 million, with Vietnam and Indonesia dominating the share. Meanwhile, job share growth based on the technology is most robust in hydropower and solar. As new plants are established during the early years, job creation will be relatively higher, especially in manufacturing and construction. Further refinement of methodologies and continuous data improvement is vital to allow the better projection of the region’s workforce on energy transition and provide opportunities for better coordination, planning, and investment to improve employment outcomes.
The Future of Nuclear Power: A Philippine Perspective
Authors: Macmac Shaina D. , Tizon Zhane Ann M. , Ocampo Erin Samantha G. , Almendrala Michelle C. , Evidente Ralph Carlo T.
Published: August 2023

A global transition toward sustainable energy systems is of capital importance to avert the adverse effects of climate change. However, at the forefront of this paradigm shift remains energy security as a key constituent. The Philippines, amid imposing high electricity rates because of the importation of coal and fossil fuels, continuously struggles with its energy consumption. As it commits to a 75% reduction and avoidance of greenhouse gas (GHG) emissions by 2030, the Philippines endeavors steps toward meeting its concomitant energy demand while investing in more sustainable energy sources. Among the most viable options, nuclear energy is integral in providing a zero-emission clean energy source to address the demand while attaining the country’s commitment to GHG reduction. Thus, national policy discussions on the introduction of nuclear power in the energy mix are of principal interest as its inclusion is projected to present colossal potential and prospects for the government and its people in terms of employment, energy security, and a sustainable environment. In lieu, this paper pivots on the future of nuclear power in the Philippine context through a comprehensive review of the status of its energy sector, the historical context and status of its nuclear power, public acceptance, capacity building, and economic feasibility.
Rehabilitation Strategy for Restoration of Riverbank Protection Function in the Merawu Watershed, Banjarnegara Regency
Authors: Sukmawati J G , Widiyatno  , Suryatmojo H
Published: August 2023

Riverbank is a buffer zone for the river ecosystem and the surrounding land. The significant land use changes and land cover reduction in the Merawu Watershed had put pressure on the riverbank and threatened the protection function sustainability. Thus, this study aims to 1) identify the riverbank’s ecological status, 2) identify its Protection Carrying Capacity (PCC), 3) determine the indicative location of rehabilitation, and 4) develop a rehabilitation strategy for restoring the riverbank protection function. The Riparian Quality Index (RQI) results indicated riverbank ecological degradation and deviation from natural conditions due to intensive tillage. The entire riverbank PCC status was poor due to less land cover in dryland agriculture and mixed dryland agriculture. Three indicative locations of rehabilitation were prioritized, i.e., Karangkobar (54.86 ha), Kalibening (41.21 ha), and Wanayasa Sub-districts (39.31 ha). Recommended riverbank rehabilitation strategies were 1) constructing bunds and bench terraces in sloping land, 2) implementing trees along the border (hedgerow) pattern and riparian buffer strips to increase land cover on cultivated riverbank lands, and 3) constructing gully plugs and retaining dams to strengthen riverbanks; using organic mulch; and planting the recommended species (Falcataria falcata, Artocarpus altilis, Dendrocalamus asper, and Gigantochloa apus) on degraded critical lands.
Enhancement of Hydrodearomatization Catalyst by Brönsted Acid Site of Al2O3 Support for Clean Diesel Production
Authors: Henpraserttae Suparoek , Buarod Eumporn , Goodwin Vituruch , Saisirirat Peerawat , Yoosuk Boonyawan , Chollacoop Nuwong
Published: August 2023

Exhaust from diesel engine contributes a main part in both PM10 and PM2.5 problem. Polycyclic aromatic hydrocarbons (PAHs) in diesel fuel should be considered because of their toxicity. Worldwide Fuel Charter recommends the PAHs content less than 2 wt.% in diesel fuel for less toxic of diesel exhaust emission. Nickle Molybdenum Sulfide over Gamma alumina (NiMoS/γ-Al2O3) catalyst is generally used in hydrotreating processes of petroleum refinery. PAHs are saturated by hydrogenation reaction (HYD) to be mono-aromatic or non-aromatic, called Hydrodearomatization (HDA) process. However, NiMoS/γ-Al2O3 catalysts still require improvements of HYD activities. Gamma alumina has been widely used as catalyst support, which generally possesses only Lewis acidity. This work focuses on surface modification of γ-Al2O3 by ammonium fluoride to generate Brönsted acidity, which could improve HYD function of NiMoS catalysts. All γ-Al2O3 supports were characterized by In-situ pyridine adsorption Diffuse Reflectance Infrared Fourier Transform spectroscopy (Pyridine-DRIFT). Increment of fluorine content in the modified γ-Al2O3 leads to increase its Brönsted acidity. The NiMoS over modified γ-Al2O3 exhibits higher HYD activities than that of the γ-Al2O3. Generation of Brönsted acidity on ϒ-Al2O3 support can enhance the HYD function of NiMoS catalyst for HDA process of clean diesel production.
Destabilization of Emulsion Oil Separation by using Chemical Coagulation Process: Preliminary Investigation for Effective Analysis
Authors: Bou Kimhor , Poev Sakada , Chan Rathborey , Ham Phaly , Bun Saret
Published: August 2023

Removal of pollutants produced by industrial plants requires reusing of water and access to the environment standard. The chemical coagulation process is a convectional method for wastewater treatment to reduce chemical oxygen demand and total suspend solids. The objective of this work is to study the effect of initial pH, coagulant type, and chemical dosage used on the separation performance at different initial oil concentrations. Based on the result, 800 mg/L of aluminum sulphate could remove up to 80% of 1g/L and 2g/L residual oil in wastewater, whereas residual 3g/L of that in wastewater with pH ranging from 7 to 8 could be removed up to 90%. In the instance of ferric chloride, the high removal efficiency of residual oil in wastewater could be achieved by utilizing a coagulant concentration ranging from 500 mg/L to 900 mg/L. Results show that, 700 mg/L of ferric chloride could remove up to 90% of residual oil in synthetic wastewater (1 g/L, 2 g/L, and 3 g/L). However, the aluminum sulphate could only remove 60–85 % of the total oil within the same dosage. In summary, further study on the possibility of ferric chloride in removing residual oil from wastewater could be considered.
Development and characterization of biological sutures made of cell-assembled extracellular matrix
Authors: Borchiellini Paul , Rames Adeline , Roubertie François , L’Heureux Nicolas , Kawecki Fabien
Published: August 2023

Most vascular surgical repair procedures, such as vessel anastomoses, requires using suture materials that are mechanically efficient and accepted by the patient’s body. These materials are essentially composed of synthetic polymers, such as polypropylene (ProleneTM) or polyglactin (VicrylTM). However, once implanted in patients, they are recognized as foreign bodies, and the patient’s immune system will degrade, encapsulate, or even expel them. In this study, we developed innovative biological sutures for cardiovascular surgical repairs using Cell-Assembled extracellular Matrix (CAM)-based ribbons. After a mechanical characterization of the CAM-based ribbons, sutures were made with hydrated or twisted/dried ribbons with an initial width of 2 or 3 mm. These biological sutures were mechanically characterized and used to anastomose ex vivo animal aortas. Data showed that our biological sutures display lower permeability and higher burst resistance than standard ProleneTM suture material. In vivo carotid anastomoses realized in sheep demonstrated that our biological sutures are compatible with standard vascular surgery techniques. Echography confirmed the absence of thrombus and perfect homeostasis with no blood leakage was obtained within the first 10 min after closing the anastomosis. Finally, our findings confirmed the effectiveness and clinical relevance of these innovative biological sutures.
Effectiveness of successive booster vaccine doses against SARS-CoV-2 related mortality in residents of long-term care facilities in the VIVALDI study
Authors: Stirrup Oliver , Shrotri Madhumita , Adams Natalie L , Krutikov Maria , Azmi Borscha , Monakhov Igor , Tut Gokhan , Moss Paul , Hayward Andrew , Copas Andrew , Shallcross Laura
Published: August 2023

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused severe disease in unvaccinated long-term care facility (LTCF) residents. Initial booster vaccination following primary vaccination is known to provide strong short-term protection, but data are limited on duration of protection and the protective effect of further booster vaccinations.

Objective

To evaluate the effectiveness of third, fourth and fifth dose booster vaccination against SARS-CoV-2 related mortality amongst older residents of LTCFs.

Design

Prospective cohort study.

Setting

LTCFs for older people in England participating in the VIVALDI study.

Methods

Residents aged >65 years at participating LTCFs were eligible for inclusion if they had at least one polymerase chain reaction or lateral flow device result within the analysis period 1 January 2022 to 31 December 2022. We excluded individuals who had not received at least two vaccine doses before the analysis period. Cox regression was used to estimate relative hazards of SARS-CoV-2 related mortality following 1–3 booster vaccinations compared with primary vaccination, stratified by previous SARS-CoV-2 infection and adjusting for age, sex and LTCF size (total beds).

Results

A total of 13,407 residents were included. Our results indicate that third, fourth and fifth dose booster vaccination provide additional short-term protection against SARS-CoV-2 related mortality relative to primary vaccination, with consistent stabilisation beyond 112 days to 45–75% reduction in risk relative to primary vaccination.

Conclusions

Successive booster vaccination doses provide additional short-term protection against SARS-CoV-2 related mortality amongst older LTCF residents. However, we did not find evidence of a longer-term reduction in risk beyond that provided by initial booster vaccination.
Factors that influence older adults’ participation in physical activity: a systematic review of qualitative studies
Authors: Meredith Samantha J , Cox Natalie J , Ibrahim Kinda , Higson Joanna , McNiff Jessica , Mitchell Stephanie , Rutherford Matthew , Wijayendran Anusan , Shenkin Susan D , Kilgour Alixe H M , Lim Stephen E R
Published: August 2023

Background

Despite the advantages of physical activity (PA), older adults are often insufficiently active to maximise health. Understanding factors that influence PA engagement will support well-designed interventions for older people. Our aim was to review the qualitative evidence exploring the factors affecting older adults’ engagement in PA.

Methods

We searched six electronic databases for studies of community-dwelling older adults (≥70 years) including qualitative methods. We excluded studies of a single-disease group, individuals with cognitive impairment and care home residents. Methodological rigour was assessed with the Critical Appraisal Skills Programme, and framework synthesis was applied using the Capability Opportunity Motivation—Behaviour (COM-B) model, which hypothesises that behaviour is influenced by three factors: capability, opportunity and motivation.

Results

Twenty-five studies were included in the review (N = 4,978; mean 79 years) and 32 themes were identified. Older adults’ capability was influenced by functional capacity (e.g. strength) and perceived risk of injury from PA (e.g. falls). Opportunity was impacted by the environment ‘fit’ (e.g. neighbourhood safety), the availability of social interaction and socio-cultural ageing stereotypes. PA was motivated by identifying as an ‘exerciser’, health gains and experiencing positive emotions (e.g. enjoyment), whereas negative sensations (e.g. pain) reduced motivation.

Conclusions

The qualitative synthesis showcased a complex web of interacting factors influencing PA between the sub-domains of COM-B, pinpointing directions for intervention, including a focus on whole systems approaches. There was a lack of research exploring PA influences in the oldest old and in low-income countries. Future research should seek to involve under-served groups, including a wider diversity of older people.