bluuebunny/crossref_metadata_2025 huggingface dataset:
Disaster mapping as decision support system to decrease abrasion impact due to climate change in Bantul Coastal Area
Authors: Naufal M , Nandini M , Rahmanu Y A , Najib D W A , Kusumaningrum P B , Ahyar M I , Hizbaron D R
Published: August 2019

Global climate change affects the physical condition of coastal areas, one of which is the rise in wave height. The increase in wave height allows higher volume of carried substrate on the swash and backwash motions. These events have an impact on increasing the abrasion intensity, specifically on the coastal areas which consist of sand material (beaches). Coastal area of Bantul Regency is one of the areas exposed to abrasion because it is directly facing the Indian Ocean. Application of atmospheric science and technology is needed to reduce the impact of losses caused by abrasion. Disaster mapping is an effort to reach that expectation. This research aimed (1) to identify abrasion susceptibility, and (2) to analyse social vulnerability due to abrasion in Bantul coastal area. The assessment was done by GIS-based spatial-multi criteria analysis to process physical and socio-cultural aspects in regards of abrasion, which the analytical unit was the coastal area between Opak and Progo River estuaries. This research resulted in susceptibility map and social vulnerability map as references for coastal mitigation directives supporting the resilience of region and community towards climate change.
Rice plantation projection based on scenario representative concentration pathways (RCP) 4.5 in West Java Province
Authors: Hidayat N M , Agustina L , Wibawanty D R , Safril A
Published: August 2019

Climate change is characterized by the changing of weather and climate elements in the earth, such as temperature and precipitation over a long period. The changing of these climate elements will affect the water balance then affect the agricultural management system, especially in timing and cropping patterns. This study aims to explain the projection of climate change result in the future and its relation with the changing of planting time and crop patterns of rice in West Java Province based on Representative Concentration Pathways (RCP) 4.5 scenario from 2006 until 2040. The data used in this study were observation data of temperature and rainfall in period of 2006-2015 from 39 rainfall posts with the height data of each rainfall post. The analysis conducted in this study was based on Thorntwaite and Matter water balance models by using observation data (2006-2015) as the baseline and future periods (2021-2030 and 2031-2040). Air temperature and rainfall data in period of 2006-2015 were used to correct the model data. Calculation of groundwater availability was calculated for each representative of Oldeman climate type. Furthermore, the rice planting schedule can be known when the condition of the level of groundwater availability reaches field capacity. The results of the analysis show changes in the Oldeman climate type and the level of groundwater availability due to changes in air temperature and rainfall parameters resulting from projections on current conditions. This caused a change in the planting schedule. The planting schedule will start early when the climate type turns wet, so the condition of the level of groundwater availability increases. The planting schedule in September was seen more broadly in the East and West parts of West Java in the period of 2021-2030 compared to the period of 2006-2015 and 2031-2040.
Urban Heat Islands analysis towards topographic based land use change and daily commute effect along the Kaliurang Street in Yogyakarta
Authors: Suarma U , Hapsarini S A , Isnastuti N L , Ikhwani H R , Durrotunafisah
Published: August 2019

This paper’s aim is to analyse the correlation between land change pattern and its topography with Urban Heat Islands (UHI) in Kaliurang Street and surrounding area. Secondly, the effects of daily commuting activities from rural or sub urban area towards urban area are well identified. Kaliurang Street is one of the major streets in Sleman that uniquely represented the transition between rural, suburban, and urban area. Rural area is located in the furthest north, suburban located in the center, while the urban area is located in the southern part. Transect method carried out along Kaliurang Street to obtain primary data mainly temperature and vehicles number. Data collected during daytime (between 12-2 PM) and afternoon (between 3 to 5 PM). Furthermore, LANDSAT 8 OLI/TIRS satellite imagery was analyzed to obtain the Land Surface Temperature (LST) Information, while ALOS PALSAR was analyzed to obtain elevation data. One of the causes of temperature differences is the commuting which affects the variation of surface temperature along Kaliurang Street. Therefore, strong correlation between commuting and the UHI phenomenon are expected.
The influence of environmental conditions (vegetation, temperature, equator, and elevation) on tropospheric nitrogen dioxide in urban areas in Indonesia
Authors: Syafei A.D , Irawandani T. D , Boedisantoso R. , Assomadi A. F , Slamet A. , Hermana J.
Published: August 2019

Nitrogen dioxide (NO2) is one important species in the tropospheric layer that has a contribution towards air quality. In urban areas in Indonesia, urbanization and growing industrial activities have increased rapidly, which may have affected tropospheric NO2. This study investigates the effect of green spaces and other environmental variables (e.g., temperature, city, distance from the equator) had on tropospheric NO2 in over thirty (30) urban areas in Indonesia between 2007 to 2016. Data on land cover were obtained from Google Earth’s satellite imagery data, tropospheric NO2 readings came from Metop-A, and information on temperature was obtained from the Terra MODIS satellite. Our results show an annual decrease in green space over 10 years in all urban areas except Surabaya. Multiple linear regression analysis also reveals that a decline in vegetation decreases tropospheric NO2 significantly. Other influential environmental factors are surface temperature and distance to the equator. Despite a promising model being obtained from this study, adding variables is important to improve the forecasting.
Diurnal Pattern of PM10 and CO in Riau as a Forest Fire Risk Area
Authors: Sumaryati  , Budiwati T , Indrawati A , Syahrial
Published: August 2019

PM10 and CO are air pollutants emitted by fossil fuel combustion and biomass burning have the bad impact on human being. Riau as a forest fire risk area, it is supposed that air quality related to PM10 and CO affected by the fire. This paper studies diurnal pattern of PM10 and CO in Riau during 2015 when a strong El Nino phenomena occurs. The diurnal pattern of pollutant is useful for hazard mitigation of the pollutant especially when its concentration reaches maximum and potent to exceed the threshold value of ambient air quality. The result of the study shows plot scatter of PM10 and CO has got the correlation coefficient of 0.72 when no fire period and 0.91 when fire period. The strong correlation in fire period is caused by the similarity of major sources of biomass burning that ignored other sources. Both diurnal patterns, especially CO shows a bimodal shape when no fire period, and the pattern changes to being flat all of the day when a great forest fire occurs in Riau and its surrounding. The bimodal shape was characterized by two concentration peaks in the morning at 08.00 and in the evening at 20.00 local time that was related on rush hour, atmospheric stability, chemical reaction rate of CO. During one year of el Nino phenomena in 2015, CO concentration is still below national air quality standard although in a great fire period and the diurnal peak concentration, while PM10 concentration in some days in fire period exceeds the national air quality standard.
Forecast of Tropical Cyclone Occurrences based on Fuzzy Logic Algorithm
Authors: Irawan A M , Nugroho H A , Simanjuntak P P , Sugiarto S I
Published: August 2019

Most studies of the tropical cyclone (TC) forecasting are focused on the track and the wind radius forecasting, even though a tropical cyclone formation alerts also developed. This paper takes a different approach and explores and forecast the TC occurrences. This study presents the development of fuzzy logic (FL) models for predicting the occurrence of TC from five primary TC genesis parameters. These parameters are low-level relative vorticity (θ), horizontal wind of upper troposphere (u), sea surface temperature (SST), equivalent potential temperature (θe), and specific humidity (q). The FL model was developed by employing the trapezoidal and triangular fuzzy membership functions for the input and output variables. The fuzzy rules were inferred from the TC genesis parameters data, with a daily calculation period from 1989 to 2018. The amount of TC genesis parameters when the cyclone occurred of the lowest, middle, and upper tercile reconstruction was used as a threshold to build FL model. The model satisfactorily simulated the occurrence of TC with comparable error measures. The result exhibits the accuracy at 0.75 (range: 0 to 1, perfect score: 1). The evidence shows that the result provides insights into the adequacy of FL methods for forecasting the TC occurrences.
Indonesian Climate under 2°C and 4°C Global Warming: Precipitation Extremes
Authors: Supari  , Sopaheluwakan A , Linarka U A , Rizal J , Satyaningsih R , Chung J X
Published: August 2019

The Paris Agreement, signed in 2015, is intended to limit global warming well below 2°C. This paper is aimed to assess the potential key impact of 2°C and 4°C global warming on the characteristics of precipitation extremes over Indonesia. For this purpose, the CSIRO-Mk3.6.0 global projections forced by the representative concentration pathway (RCP8.5) scenario is dynamically downscaled using the RegCM modelling system. The results show that under these two global warming level, total annual precipitation (PRCPTOT) will decrease in most regions. Consistently, the dry spell duration (CDD, consecutive dry days) is projected to increase. On the other hand, the frequency and the intensity of precipitation extremes (R50mm and RX1day) are projected with mix increase and decrease tendency. Seasonally, the contrast changing of PRCPTOT is projected. PRCPTOT tends to decrease during dry season (June-July-August, JJA) and tends to increase during wet season (December-January-February, DJF). The similar pattern is found for other indices e.g. CDD, R50mm and RX1day. In general, changes at 4°C global warming are statistically more significant and more intensified compared to that at 2°C. Our findings suggest the benefit of limiting global warming at a lower level.
Sensitivity of Planetary Boundary Layer Scheme in WRF-Chem Model for Predicting PM10 Concentration (Case study: Jakarta)
Authors: Musthafa M , Turyanti A , Nuryanto D E
Published: August 2019

Weather Forecasting-Chemistry (WRF-Chem) is an air pollution model that combines meteorological factors and atmospheric chemistry simultaneously (online coupled). Many schemes selected on WRF-Chem according to boundary layer conditions of the study area. The objectives of this study were to evaluate WRF-Chem model and analyze the sensitivity of Yonsei University (YSU) scheme and Mellor Yamada Janjic (MYJ) scheme as physical boundary layer parameters, especially for Jakarta region. Particulate matter 10 micrometers or less in diameter (PM10) selected as the air pollutant parameter. The model outputs compared to observational data in five locations in Jakarta. The regression analysis between air temperature data shows that the values of R2 are 0.5 - 0.6 in February and 0.5 - 0.9 in August. Another result, the wind velocity from WRF-Chem overestimates but the hourly averages have a similar diurnal pattern with the observation. The PM10 concentration model output is underestimated which is caused by local emissions that are not accommodated in the model. The sensitivity analysis shows a higher sensitivity index for MYJ than YSU scheme, especially in August, so the model outcome of the MYJ scheme has a good response to the observations in Jakarta. It is seen that the extreme concentration of PM10 produced through the WRF-Chem with both schemes in February and August have the same time in morning. The model output of WRF-Chem through both schemes also demonstrate the minimum concentration of PM10 that follows during afternoon. The Planetary Boundary Layer (PBL) height analysis shows that in morning until noon, the PBL height with MYJ scheme is lower than YSU. It is different for other hours, that from the afternoon through the night until next morning, the height of PBL with MYJ scheme is thicker than YSU. At the point when the PBL is high, the pollutants assorted in a more volume so the estimation of the pollutant concentration estimated on the surface will be reduced.
Comparison of seasonal prediction outputs based on dynamic atmosphere model and observations (case study: seasonal prediction in 2016 - 2017)
Authors: Satyawardhana H , Gammamerdianti
Published: August 2019

Seasonal predictions are considered as an important factor for many sectors in Indonesia, especially for the agriculture sector. In Indonesia, the variability of seasonal characteristics is influenced by various regional atmospheric phenomena, such as monsoon, ENSO, and IOD. With such urgency, this research is conducted using dynamic models to generate accurate medium-term predictions. The dynamical atmospheric model, Cubical Conformal Atmospheric Model (CCAM) is used to produce daily predictions up to 8 months. CCAM result has been tested on major islands in Indonesia such as Java, Sumatra, Sulawesi, Borneo and Papua. It shows that during the rainy season, the value of rainfall predictions is lower than observations. Meanwhile, the rainfall predictions are overestimate when compared to observations during dry season. Nevertheless, the patterns of rainfall predictions are following satellite rainfall observations patterns, especially in Java.
The Indonesia In-House Radar Integration System (InaRAISE) of Indonesian Agency for Meteorology Climatology and Geophysics (BMKG): Development, Constraint, and Progress
Authors: Permana D S , Hutapea T D , Praja A S , Paski J A I , Makmur E E S , Haryoko U , Umam I H , Saepudin M , Adriyanto R
Published: August 2019

In 2017, BMKG has 41 weather radars covering most of Indonesia region and most of its data are automatically sent to the BMKG headquarter every 10 minutes. There are four different weather radar brands with its specific data format and software analysis. In recent years, the weather radar community has developed open-source software to handle several radar data formats. Based on this, BMKG has developed the Indonesia In-House Radar Integration System (InaRAISE) of BMKG using the open-source weather radar software. InaRAISE has been developed using Python-based libraries Wradlib and Py-ART for processing weather radar data. BMKG radar data have been successfully extracted and transformed into Cartesian coordinates for post-processing. The multiple radars have been successfully composited by comparing column-maximum reflectivity. Web-based near real-time radar images has been experimentally operated, but not officially launched. The main constraint is the susceptible communication network between radar sites and BMKG headquarter causing real-time data transfer problems. InaRAISE serves feasible data radar extraction for data assimilation in the numerical weather prediction model. InaRAISE could serve as a supporting of the existing radar integration system or possibly as a replacement.
WRF-3DVAR Radiance Data Assimilation Impact for Convective Rain Prediction on Jakarta
Authors: Fatmasari D , Rosita Dewi D M P , Gustari I
Published: August 2019

Weather Research and Forecasting (WRF) is an open source numerical weather prediction model, but one of the main problems is the inaccuracy of initial condition that impacts the accuracy of weather predictions. Techniques that can be used to improve initial condition is to assimilate satellite radiance data using Three-Dimensional Variation (3DVAR) method. The Global Forecast System (GFS) data were used as initial conditions which were assimilated with several radiance data such as from AMSU-A sensors, MHS sensors, and ATMS sensors. The purpose of this study was to compare the effect of data assimilation on the initial condition model and the rainfall prediction for convective precipitation on February 24, 2016 in Jakarta. The results showed there is a clear flow of moisture to the northern part of Jabodetabek area that cause the model captured a high relative humidity which results in the heavy rain. The result of the study obtained different rainfall prediction between non-assimilation model and assimilation model. In general, both models have underestimated rainfall, but satellite radiance data assimilation is better able to describe the convective rain patterns and has better accuracy on the convective rainfall accumulation per hour.
Numerical Analysis using Empirical Orthogonal Function Based on Multivariate Singular Value Decomposition on Indonesian Forest Fire Signal
Authors: Septiawan P , Nurdiati S , Sopaheluwakan A
Published: August 2019

Over the past years, fires have burn Indonesian forest annually. The strength of the fire and many of fire points is vary each year. In 1997 there was 9.75 million ha forest burned in one year with 206,6 million ton of carbon emissions. In 2015 there was 2.089 million ha forest and 805 million tons carbon emissions. Both years involved the biggest incidences of burned forest in Indonesia. The purpose of this research is to analyze the pattern of burned forest in Indonesia and to analyze linkages of variables that affect it. Datasets that used in this research is monthly data from 1997 until 2016 Global Fires Emissions Database (GFED) with variable burned area, GFEDs with variable carbon emissions, and Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS). Using Singular Value Decomposition and Empirical Orthogonal Function analysis, for the overlapping period detected that there is annual signal that dominate the incidences of fires in Indonesia, especially in Riau, Palembang, South Kalimantan and Central Kalimantan. There was 4 annual signal that can explain 72% of fires incidences in Indonesia in 1997-2016. In Riau there is another signal that have 6 months period caused by 6 months rainfall period.
Identification of rainfall area in Indonesia using infrared channels of Himawari-8 Advance Himawari Imager (AHI)
Authors: Risyanto  , Lasmono F , Nugroho GA
Published: August 2019

The study aims to investigate the use of Infrared (IR) channels of Himawari-8/AHI for identification of rainfall area in Indonesia. The parameters used include the IR brightness temperature (BT) at 10.4 microns (T10.4) and seven IR BT differences (BTD), which were inferred as proxies for cloud properties. Identification of rainfall in this study is based on lookup table (LUT) approach, which is used to create probability of rainfall map. The LUTs were developed by combining the IR at 10.4 microns and IR BTD with the transportable X-band radar data, gathered during the campaign period on 15 March – 5 May 2017. Statistical skill scores were used in the study to determine the overall performance of the methods. The study indicated that the best IR and BTD combination to identify rainfall area is from the bands correlated to cloud-top height proxy (T10.4 and BTD 13.3- 10.4). In visual comparison with Global Satellite Mapping of Precipitation (GSMaP) hourly rainfall image, this IR-BTD method produced rain maps with high similarity. In general, almost all IR-BTD combinations could be used to identify rainfall area with comparable results. However combination of T10.4 and BTD at 6.2 & 7.3 micron generate high false alarm rates and underestimate the area of rainfall.
Identification of The Influence of Long Winter Season in 2017 – 2018 to the Forming of Strong Northerly Cold Surge over West Indonesia
Authors: Nugroho Y A , Fajarianti R , Imami A F R , Winarso P A
Published: August 2019

This study identifies the characteristic of strong Northerly Cold Surge (NCS) over West Indonesia in the period from November 2017 until April 2018. Usually the NCS occurs in the DJF period that indicates the rainy season that usually goes to trigger some serve weather in Indonesia. The severe weather accompanying the intense northerly cold surge often brings more major disruptions that often trigger natural disasters like floods and landslides to the affected regions in West Indonesia. Descriptive and statistical methods are used in this study by classifying the intensity of NCS in November 2017 until April 2018. The real-time data from Ogimet Weather Information Service, GSMaP Satellite, and restudy data from National Centers for Environmental Prediction (NCEP) are used to determine the 925 millibar meridional wind, relative humidity in 1000, 925, 850, and 700 millibar, mean sea level pressure, and rainfall estimation to identify the passage of NCS in West Indonesia region. The long winter season in 2017 – 2018 triggered the NCS to stay active even it comes to March and April 2018. It is proven by the natural disaster that comes from consecutive intense rainfall like floods and landslides that still intensively occurred in the March until April 2018 in West Indonesia.
Examination of bark content for different species of short rotation coppice
Authors: Szalay D , Papp V , Hodúr C , Czupy I
Published: August 2019

Short rotation coppices (SRC) can produce large amount of dendromass in a short time. From an energetic point of view, one of the most important challenges are the outstanding amount of ash content, which is primarily generated due to the high bark content of the thin shoots. Our research was carried out for measuring bark content of four species/clones performed in three different vegetation years. The experimental plantation is located in the northwestern part of Hungary. The results show that the bark content strongly depends on the applied harvest frequency and tree species. Based on the measurements, the Robinia pseudoacacia and the Salix alba species have the largest bark content in the first year but the value can be reduced by around 50% by using longer harvest rotation. Having analyzed the whole stem, the bark percentage of the Populus x euramericana clones increased from 5.5% to 33.7% from the cutting height to the tip. The minimum value was at the diameter class of 24-28 mm. In the case of Robinia pseudoacacia the bark content ranges only between 3.0% and 20.0%.
Research and implementation of substation clock unsynchrony alarm system based on GPS pulse
Authors: Zhang Chuan-yu
Published: August 2019

In order to change the status quo within the substation bay control devices which only passive receiving IRIG-B GPS clock code or PPS, for the purpose of the research and the realization method of substation clock unsynchrony alarm system based on GPS pulse. On the basis of existing substation SCADA system and GPS time synchronization system, this paper realizes the real-time monitoring of time synchronization of substation bay control devices by simple modification and introduction of simple algorithm. This paper describes in detail the system construction method and relative time difference algorithm, as well as the project implementation method, to achieve the correct and punctual on-line monitoring of the bay control device, effective control of substation accidents caused by device time unsynchrony, greatly improving the stability of substation operation.
Acid-catalysed hydrolysis kinetics of sugar cane bagasse to glucose and xylose in selected ionic liquid media
Authors: Gao Y , Bandara T R , Griffin G J
Published: August 2019

The process of converting lignocellulosic biomass to fuels (such as ethanol) is considered a potential method for supplanting current fossil fuels with renewable sources. A significant inhibitor to such processes is the lack of an efficient and economical means by which hemicellulose and cellulose may be hydrolysed to their constituent monosaccharides as precursors for ethanol fermentation. This research details experiments conducted by which sugar cane bagasse (SCB) immersed in ionic liquids (either 1-butyl-3-methylimidazolium chloride or 1-ethyl-3-methylimidazolium chloride – BmimCl and EmimCl respectively) were catalysed to glucose and xylose by adding variable amounts of hydrochloric acid (3.5 – 10.5wt%) at temperatures between 100°C to 140°C. Experiments were conducted over 5 hours and in all experiments the monosaccharide concentrations increased to a maximum then decreased as the monosaccharides were degraded to other products. Maximum yields of glucose and xylose of 133mg/g bagasse and 125mg/g bagasse respectively were achieved although under different reaction conditions. The kinetics of the process was modelled as a simple set of first order reactions for the conversion of biomass to sugars then the degradation of sugars to other products.
Controlling chemical industrial pollution with regulatory tools: the case of Yichang, Hubei, China
Authors: Wang Haijing , You Mingqing
Published: August 2019

Chemical industries may pollute the air, water, and soil as well as jeopardize the ecological system and human health. China has established a relatively comprehensive regulatory regime to control industrial pollution, including pollution from chemical industries. This paper evaluates various regulatory tools to find their efficacy and appropriateness, and uses Yichang, a city rich in phosphate ore and phosphate industries, as an example. This paper integrates qualitative research methods and quantitative research methods. The analysis indicates that regulatory tools can be effective in controlling environmental pollution and restoring the jeopardized ecology. It also indicates that the Chinese government can enforce the environmental law effectively. However, these regulatory tools are also costly, insufficiently clear, and may not be effective for each place.
CO2 sequestration potential of log homes
Authors: Pásztory Z , Hegedűs T , Börcsök Z
Published: August 2019

Beside the reduction of greenhouse gas emission the adsorption and bounding of carbon dioxide is also an important issue to protect the environment from irreversible harms. By photosynthesis produced wood material mostly built up from the CO2 content of the atmosphere and it is stored until burning or natural decay of the material. Log homes sequester significant amount of wood for longer time and the amount in cubic meter and the carbon dioxide equivalence were examined in this case study. Wood content of 80 log homes were investigated and the average of 35.28 m3 was found. The average stored carbon dioxide per log homes was 31 tons, and there is slight difference between one and two storied buildings 0.214 and 0.284 tons of equivalent carbon dioxide per layout square meter respectively. The ceiling height influences the wood content of the building significantly and the variation is higher in the case of two-storied buildings.
The fate of carbon in two-stage anaerobic digestion of vegetable waste
Authors: Dinh P V , Fujiwara T , Giang H M , Pham Phu S T
Published: August 2019

This study aims to investigate the fate of carbon in two-stage anaerobic digestion (TAD) of vegetable waste. The TAD including a hydrolytic reactor and a methane reactor were controlled at mesophilic temperature (36 ± 1°C) with a retention time (RT) of 9 days and 20 days, respectively. Carbon tracking was conducted step by step throughout the system. Non-hydrolysable carbon accounted for a significant proportion of total initial carbon (25%). Meanwhile, a large amount of carbon in the feedstock (23.5%) was hydrolysed but remained in the effluent including water and suspended solids. It was mostly inorganic carbon which is not harmful to the environment. The only 41.3% initial carbon was converted to biogas in both reactors. In the hydrolytic reactor, biogas was mainly carbon dioxide (99%), accounted for 11.3% of total biogas and 35.8% of total CO2 product. In the methane reactor, biogas was 373.9 Nml/g-VS including 73.3% CH4, 21.9% CO2 and 4.8% others. Non-hydrolysable materials can be a source of thermal energy. Meanwhile, a large amount of hydrolysed carbon was not converted into biogas, was still in the effluent, it was a significant energy loss. Therefore, how to further increase the effectiveness of TAD is an issue that needs to study.
Wear-corrosion response of Cerium oxide reinforced Cobalt hybrid composite layers in biological solution
Authors: Simionescu N , Benea L , Celis J P
Published: August 2019

The research work aims at improving biomaterials surface properties by Co/nano-CeO2composite layers obtained by electro-codeposition method from a cobalt sulphate solution containing CeO2dispersed nanoparticles. The thicknesses of pure cobalt and Co/CeO2hybrid nanocomposite layers are measured versus applied current density and time of the plating process. The tribocorrosion properties of Co/nano-CeO2hybrid nanocomposite layers and pure Co layer obtained were comparatively investigated friction sliding tests in a unidirectional tribometer in lubricating conditions using biological solution (Hank). During the tribocorrosion test, the normal force, tangential force, coefficient of friction, number of cycles as well as the electrochemical parameter (potential), were continuously monitored. The results show that the wear - corrosion (tribocorrosion) behavior of Co/nano-CeO2hybrid nanocomposite layers are closely related with dispersed reinforcing nano-CeO2content. The hybrid nanocomposite layers with all CeO2content shows increased wear - corrosion resistance as compared with pure Co layer, by decreasing wear volume loss with increasing nano-CeO2particles dispersed into plating electrolyte.
Effect of the inflammatory conditions and albumin presence on the corrosion behavior of grade 5 Titanium alloy in saliva biological solution
Authors: Dragus L , Benea L , Simionescu N , Ravoiu A , Neaga V
Published: August 2019

The field of biomaterials imposes a multidisciplinary approach that requires the involvement of sciences such as biology, medicine, chemistry and materials engineering so that the material implanted in a living organism does not cause any adverse reaction. This research area of biomaterials is considered as fascinating and challenging. It's fascinating because of its potential applications and the need to improve the quality of life. It is challenging due to the various complexities it faces when biomaterials encounter biological environments for the longevity of life by maintaining or restoring tissue or organ functions. Metallic biomaterials are used as pivots for anchoring dental implants and as parts of orthodontic devices such as crowns and bridges of prostheses. Ti-6Al-4V is well known as a corrosion resistant alloy for dentistry applications due to this film of titanium oxide formed on its surface. However, the inflammatory conditions ad protein presence could affect the corrosion resistance of this alloy. Our research work aims to investigate the effect of albumin and inflammatory conditions to corrosion resistance of Ti-6Al-4V in saliva Fusayama Meyer biological solution. In order to simulate the peri-implant inflammatory conditions in vitro studies were conducted with addition of hydrogen peroxide (reactive oxygen species, found during inflammation) and albumin the most typical protein of biological fluids. Electrochemical methods were applied for corrosion investigations. The results provide evidence that titanium’s alloy corrosion resistance is affected by inflammatory conditions and albumin presence in saliva biological solution.
Extraction of pesticide residues from plant extracts using regenerative MCM41 mesoporous materials
Authors: Florea M A , Purcareanu B , Bicu A , Drumea V , Gird C E , Grigoroscuta M , Mihaiescu D E , Vasilievici G , Olariu L
Published: August 2019

The aim of the current study was to determinate the adsorption degree of pesticide residues on MCM41 mesoporous material from plant extracts usually used in phytotherapeutic treatments. The choice of the material was based on the high adsorption capacity, due to the specific surface area, over 800 m2/g and for the possibility of their regeneration/reusability capacity. The silica matrix was synthesized starting from tetraethylorthosilicate (TEOS)- the silica source and hexadecyltrimethylammonium bromide (CTAB)- as a template agent, the whole process taking place in continuous flow at room temperature and normal pressure. The material obtained was characterized by microscopy techniques (transmission and scanning electron microscopy TEM and SEM) for determination of pores morphology, by standard method Brunauer-Emmett-Teller for pore size distribution and specific surface area (textural analysis- B.E.T), by Fourier-transform infrared spectroscopy (FTIR) for spectral fingerprint and by dynamic light scattering (DLS) for determination of hydrodynamic diameter of particles. The tests were carried out on extracts performed with organic solvents from some medicinal species (Menthae officinalis, Salvia officinalis, Matricaria chamomilla), using mesoporous material MCM41 for isolation / concentration of pesticide residues. Quantitation of pesticide residues was performed using a gas chromatograph coupled with a triple quadrupole mass spectrometer (GC-MS/MS), for both extracts and MCM41 material.
Surface properties in surfactant systems containing amino acid-based surfactants
Authors: Chican I E , Vărăşteanu D , Fierăscu I , Fierăscu R C , Deaconu M
Published: August 2019

The development of green surfactants produced from renewable raw materials at the expense of petrochemical-based surfactants took into account the increasing requirements for environmental protection and the demand of the society for sustainable development. A variety of renewable raw materials such as triglycerides, carbohydrates or amino acids are used in green surfactant synthesis. The natural structure of green surfactants induces low toxicity and high biodegradability. In this work was investigated the behaviour of surfactant systems containing synthesized amino acid-based surfactants (sodium lauroy lglycinate and sodium lauroyl sarcosinate) and amphoteric or nonionic surfactants, highlighting the differences between surfactant systems containing sodium lauroyl glycinate or sodium lauroyl sarcosinate due to nitrogen methylation of the amide nitrogen in the latter. Synergetic behaviour of aqueous surfactant systems were found, leading to improved properties in terms of surface tension and foaming power.
New refractory high entropy alloys
Authors: Voiculescu I , Geantă V , Stefănoiu R , Rotariu A , Scutelnicu E , Pantilimon M C , Mitrică D , Crăciun V
Published: August 2019

The paper presents researches on the microstructure and mechanical properties of a new types of refractory high entropy alloys, which can be used for thermal engine components as well as for military incendiary bullet. The main characteristics required for such applications are high compression resistance, microstructural stability during thermal stress, hardness and corrosion resistance. To obtain such specific characteristics, the raw materials must be melted in inert protective atmosphere, and then heat treated for the homogenization of the microstructure and chemical composition. In the paper, there have been studied three types of high entropy alloys, HfMoNiTaW, 2HfMoNi2Ta and MoNiTaW obtained in the vacuum arc remelting (VAR) equipment. The heat treatment, performed at 800 °C with a holding time of 4 hours, allows obtaining a good homogenization of the chemical composition while generating a decrease in the microhardness, from a maximum value of 637 HV0.2 to a minimum value of 527HV0.2.
Compliance behaviour on Zakat donation: A qualitative approach
Authors: Farah J M S , Shafiai M H B M , Ismail A G B
Published: August 2019

Zakat is a mandatory charity that is paid by every Muslim as part of their duty to the creator. This study examines the compliance behaviour on zakat donation. The study further defined compliance in term of religious obligation among the Fakulti Ekonomi dan Pengurusan academicians at Universiti Kebangsaan Malaysia (UKM) using a qualitative approach. This Study used interview methods with saturated sample size. The findings of this research revealed there is a diversity of commitments and obligations for compliance behaviour on zakat donation. Amongst the universal themes of zakat paying motivations namely; religious duties, knowledge about the zakat donation into the poor, confidence in the fair disbursement of zakat collection to Asnaf, a blessings from Allah, assisting Muslim society, the inspire of zakat administrators, tax repayment incentive, cleanse one’s revenue and wealth, and control of spiritual teachers. The research suggested that more empirical studies should be done within the area of compliance on zakat donation using a qualitative method since the majority of the prior studies on zakat compliance only focused quantitative method. This study also recommends the future studies might concentrate on internal or psychological obligation and donation on zakat.
Modeling the machined surface quality of an aluminum alloy using the active experiment type
Authors: Pop A B , Ţîţu M A , Pop G I , Ţîţu Ş
Published: August 2019

The surface roughness obtained by the cutting processes has always been a subject of great interest when it is intended to improve the quality of the final product requested by the customer. The objective of this scientific paper involves a comparative study on the tracking of the surface roughness measured both longitudinally and transversely in the direction of the cutting feed movement, following the end-milling process of an aluminum alloy used in the aerospace industry worldwide. Practical experiments have conducted in a prestigious company in the aerospace industry of Romania. Regarding the cutting regime, in terms of milling, a cutting speed was adopted to maintain its constant value at 570 m/min, and the cutting depth and feed per tooth are within the range recommended by the cutting tool manufacturer in aluminum machining. The measuring and control devices used to obtain the experimental data were chosen after careful analysis, such as the surface tester and the electronic microscope. With the help of the obtained data, it was possible to interpret the surface roughness results measured longitudinally in the direction of the feed motion, compared to the roughness measured transversally in the same direction of the cutting tool. Different variations of the surface roughness have highlighted with the help of profiles and microscopic analyses of the machined surfaces. This study is in the category of scientific papers with an extremely high level of applied scientific research using experimental statistical modeling of active type.
Considerations regarding WC-cermets depositions by HVOF and ESD techniques used for reinforced steel components for geothermal turbines
Authors: Buzaianu A , Trusca R , Motoiu P , Csaki I , Ioncea A , Motoiu V
Published: August 2019

The cumulative effect of erosion-corrosion process in geothermal turbines results in significant damages, especially for rotors and turbine blades; the degree in which they are affected depends on steam temperature, mechanical impact and the geothermal composition of the substances dissolved in steam. Layer composite materials are a feasible option to improve the erosion-corrosion resistance and the durability of turbine components. There cermet powders containing tungsten carbide are used for High Velocity Oxy-Fuel (HVOF) spaying and for Electro Spark Deposition (ESD) to obtain graduate microstructure and to form local hard structures. Both techniques by WC-cermet depositions were found to be most suitable to improve wear resistance, to repair rotors and blades and to provide possible life extension of geothermal turbines. The paper presents a comparative assessment of tungsten carbide and the technological parameters used for HVOF and ESD cermets layers depositions. Also, the work presents the analysis of the micro chemical composition of the microstructure, the micromechanical characterization and erosion-oxidation resistance of HVOF and ESD coatings using WC-cermets on steel substrates. The experimental procedure involved X-ray diffraction of the samples, micro mechanical tests and SEM investigations to provide specifically information about micro-morphological modifications and grade of adhesion of protective layers.
Machining of thermal sprayed coatings – a case study for self-fluxing powder
Authors: Stescu C , Chicet D , Munteanu C , Croitoru C , Cârlescu V
Published: August 2019

In this paper we studied the possibility of mechanical processing of a coating produced by atmospheric plasma spray method from nickel-based self-fluxing powder. Two samples were realized from the same alloy type - NiCrBSiFe alloyed with WC, one of which was mechanically processed in the raw state and the other after applying the self-fluxing treatment. Subsequently, their behaviour was observed during the mechanical processing. Both the morphology of the coatings after processing and their mechanical properties (using scratch method) were evaluated.
Considerations on the surface roughness of SLM processed metal parts and the effects of subsequent sandblasting
Authors: Bernevig-Sava M A , Stamate C , Lohan N-M , Baciu A M , Postolache I , Baciu C , Baciu E-R
Published: August 2019

Selective Laser Melting is an Additive Manufacturing technology based on 3D scanning of successive layers of metal powder. Three distinct values were determined for each of the three technological parameters (P – the power of the laser, Vscan – scanning speed and te – exposure time), therefore resulting nine sets for the “layer by layer” processing. After SLM processing, the samples were sandblasted simply (1S), sandblasted successively (2S), or left unsandblasted (NS). The roughness (Ra) of the outer surfaces was measured for all the samples, and there was found a decrease in the height of the micro-irregularities and the uniformization of the roughness profile along with the intensification of the sandblasting process. For some samples, there were found uncertainties regarding the accuracy of the experimental results’ values, determined by the presence of the adherent particles identified by the SEM analysis of the outer surfaces. The number and size of these particles have affected the manner in which the samples were placed on the roughness tester’s plate, as well as the accuracy of the measurements. Under these conditions, the tip of the roughness tester’s diamond stylus has recorded the specific values of the surface’s secondary profile, which is affected by the existence of the formations adhering to the primary profile of the SLM processed samples.
Al0.5CrCoFeNi high entropy alloy for Geothermal Environment
Authors: Geambazu L E , Manea C A , Csaki I , Miculescu F
Published: August 2019

Al0.5CoCrFeNi high entropy alloy was processed by mechanical alloying and investigated in term of powders characteristics and microstructures. The obtained power was pressed and sintered resulting in a bulk material that will be further processed to obtain electrodes that will be deposited on the substrate by electro spark deposition process, in an attempt to obtain a corrosion resisting coating. High Entropy Alloys are known due to their corrosion and wear resistant properties, which makes them the perfect candidates in numerous domains as marine, geothermal, oil and gas industries, where the aggressive environment tends to corrode the in work components of the equipment. The cocktail effect is characteristic to the high entropy alloys, where every component concurs in an alloy with predetermined properties.
Nanomaterials applied for heavy metals removal from wastewater
Authors: Covaliu C I , Paraschiv G , Stoian O , Vişan A
Published: August 2019

In the past years, nanotechnology has been studied and it proved that is one of the advanced ways for toxic compounds removal from wastewater. In this paper we focus on nanomaterials used for treatment of wastewater containing heavy metals. Nanoparticles have very high and specific adsorption capacity being applied in water depollution, remediation and treatment process. The depollution methods based on nanomaterials could be more cost-effective, less time and energy consuming, generating no or less waste in comparison with conventional methods. The aim of this review is to summarize the applications of nanoadsorbants within heavy metals depollution methods.
Recent graphene oxide/TiO2 thin film based on self-cleaning application
Authors: Azani A , Che Halin D S , Razak K A , Abdullah M M A B , Salleh M A A M , Mahmed N , Ramli M M , Azhari A W , Chobpattana V
Published: August 2019

Graphene oxide/TiO2 (GO/TiO2) thin films works as self-cleaning device have been developed in various method onto selected substrates. It was noticeable that graphene oxide is the best form in the group of graphene family. Under self-cleaning application, the wettability test and electroconductivity of the sample was the main characteristic for self-coating study. As planned, by addition of graphene to TiO2 films produce a highly conductivity, transparent and produced promising enhanced photocatalytic activities. Moreover, superhydrophilic properties of GO/TiO2 film surface film exhibits more as compared to TiO2 film only within a short period of time. Thus under this finding, the photocatalytic activity of GO/TiO2 films will be enhance as a result of improve charge separation efficiency because of the electron injection to graphene from TiO2 conduction band. Other factor that contribute to self-cleaning activity is the electrical conductivity of the graphene added to TiO2 thin film. The graphene added to TiO2 films have a lot of potential in various indoor application due to its fantastic characteristics such as not expensive, transparent, highly conductive, exhibits superhydrophilic properties, and very much photocatalytically active.
Extraction of nitrogen, phosphorus and potassium from food waste under elevated temperature by heat induced bath method
Authors: Kamaruddin M A , Ahmad N F , Sandu I G , Alrozi R , Sandu I , Abdullah M M A B
Published: August 2019

38,000 tonnes of waste is generated per day in Malaysia and 15,000 tonnes of that are food wastes. This waste should be recovered to produce a new valuable product that brings benefits such as fertiliser because it contains various nutrients such as proteins, carbohydrates. This study aims to determine the effects of thermal treatment on the macronutrient of food waste that collected from cafeteria of Universiti Sains Malaysia (USM). Hot water bath was employed as thermal treatment of food waste with five different temperatures (60 °C to 100 °C) with two reaction time (30 min and 60 min). The results have demonstrated increases in the percentage of nitrogen (N) and concentration of phosphorous (P) however for the concentration of potassium (K) shows inversely related after subjected to hot water bath. Thermal treatment showed the untreated sample only consists 2.13 % of N and 31.53 mg/L of P, and after the treatment resulted in an increase in N and P by 0.22 % - 3.39 % and 0.33 mg/L - 21.40 mg/L respectively. On the other hand, the concentration of K in the untreated sample is 0.4915 ppm and after treatment it decreases to 0.1051 ppm - 0.2052 ppm. Based on the range of macronutrient in organic fertilisers in Malaysia, only N was in the range and can directly employ as organic fertiliser while for P and K should undergo further treatment.