bluuebunny/crossref_metadata_2025 huggingface dataset:
Geometric correction model for dual sensor pushbroom aerial camera
Authors: Monica Donna , Maryanto Ahmad , Sunarmodo Wismu , Widijatmiko Nugroho
Published: July 2020

Geometric correction is necessary in photogrammetry and remote sensing to avoid geometric distortions and establish relationship between image coordinate and its corresponding ground coordinate. Rigorous sensor model is one of the methods which considered the most precise and accurate for geometric correction. However, as rigorous sensor model contains many equations that depend on the actual physical properties of the sensor, the model is specialized for each sensor. In this paper, we modified a rigorous sensor model of geometric correction for pushbroom imager into geometric correction model for dual sensor pushbroom imager. The result shows that a model has been successfully obtained and can be used to geometrically correct coordinates of dual sensor pushbroom imagery.
Changes of land use monitoring within forest area
Authors: Pribadi Cherie Bhekti , Hariyanto Teguh , Kurniawan Akbar , Amriana Yessherly
Published: July 2020

Pasrujambe District is one of sub-districts in Lumajang Regency which has a forest area. Forests are main source of life for people who live in surrounding villages, start from farming, logging, taking firewood, gathering, and grazing their livestock in forest areas. This phenomenon cannot be avoided from use of forest land for the other land functions, both for settlements, agriculture and other regions. Therefore, it’s needed to be related to changes of land use in forest areas. In this study an evaluation of distribution and extent of land use functions in Pasrujambe District forest area was carried out using 2 (two) methods, namely object-based classification methods and interpretation methods (digitized on screen). The results show us that there are changes of land use in forest areas in 2017, such as industries, plantations, agricultures, plantations, bushes and settlements with total area of 3764.38 Ha and for agricultural land use such as lakes, grasslands and rivers with total area of 799.41 ha.
Weekly sea surface temperature from SNPP-VIIRS data using open source software
Authors: Hartuti M , Tjahjaningsih A , Effendy I , Sitorus J
Published: July 2020

The objective of this study is to make weekly mean sea surface temperature (SST) from SNPP-VIIRS satellite data. The data used were SST data every afternoon pass, from 13 to 19 May 2019. The data were obtained from Remote Sensing Technology and Data Center, LAPAN. From 12 samples data used showed that pixel size of each data are different, with range between 0.006737548 - 0.006858158 degree. The pixel size should be exactly the same to do data overlay. Then, the pixel size was resized become 0.00675 degree. This process was carried out using Reprojection Menu in QGIS software. The next process was calculating weekly mean SST every pixel. The mean SST was calculated only on pixels that have SST values. The calculation was not carried out on cloud, cloud shadow, land, and out of coverage data. The tolerance of coordinate position between pixels are less than 0.5 of pixel size. Weekly mean SST calculation process was executed using mean function in R software. The result of mean SST showed some possible error SST values. The errors were found in these conditions: 1) in coastal areas where possible mixed pixels of land and water 2) near cloud, where possible mixed pixel of cloud, cloud shadow, and water, 3) pixels with (extremely) high SST values near clouds. To overcome these conditions, some median type filters were applied. Therefore, weekly mean SST from SNPP-VIIRS data that smooth and minimum cloud cover can be obtained.
The estimation of soil moisture using DUBOIS model (1995) for monitoring phase growth of paddy
Authors: Nurtyawan Rian , Nur Ardianti
Published: July 2020

Monitoring the growth of rice in Indonesia is very important because rice is a staple food of the Indonesian people. The biggest rice producer in West Java is Indramayu. Soil moisture is one of factor in monitoring the growth of paddy. The Monitoring is carried out using SAR image, namely Radarsat-2 Quad-Polarimetric imagery. In estimating the value of soil moisture, required a dielectric constant which is obtained from the value of the Digital Number (DN) that is converted into the backscattering value (σo). The approach that used in calculating the dielectric constant is a semi-empirical approach using the Dubois model (1995). The purpose of this study is to estimate the value of soil moisture in order that it can be used in monitoring the growth phase of paddy. The rice growth phase is distinguished in the form of a graph subsequently matched with the results of field photo validation. The results of this research show a positive linear correlation between the Dubois model (1995) and field soil moisture with a level of accuracy of ± 7.202% volumetric.
Using visible spectral-index as alternative methods for identifying levels of Ganoderma Boninese infection
Authors: Wiratmoko Dhimas , Jatmiko Retnadi Heru , Yusuf M. Arif , Farrasati Rana , Prasetyo Agus Eko
Published: July 2020

Ganoderma boninense is a major devastating disease for oil palm. The severity level identification of Ganoderma boninense on oil palm plantation is important to support the decision making on managerial activities. There have been researches conducted about the usage of unmanned aerial photograph (UAV) on oil palm plantation, nonetheless, the utilization of digital data on the visible aerial photograph has not optimally used. This study aims to obtain alternative methods to identify the severity level of Ganoderma boninense infection with visible spectral index from a visible aerial photograph (RGB). Visible aerial photograph (RGB-aerial photograph) is adopted on this research and carried out at Dusun Ulu plantation with various visible spectral-index methods. The visible spectral-index methods are the excess green index (ExG), the excess red index (ExR), the excess green minus excess red index, and the colour of vegetation extraction (CIVE). The results of four visible spectral-index methods are able to differentiate the severity level of Ganoderma boninense infection on each individual of oil palm.
Estimating the casualties of the earthquake caused by the Lembang Fault in Coblong, Bandung, Indonesia
Authors: Meilano Irwan , Riyadi Puti Nabila , Riqqi Akhmad , Kuscahyadi Febriana
Published: July 2020

Bandung is a metropolis in Indonesia located 10 km from the Lembang Fault. Being near a fault and having a dense population places Bandung at a high risk of suffering an earthquake. The lack of an earthquake risk assessment for the Lembang Fault is the main motivation of this study, which aims to provide information on the risk of building damage and estimated casualties in the Coblong District. This study uses earthquake scenarios with magnitudes of 6 and 7 caused by the Lembang Fault. Earthquake acceleration data on bedrock along with building vulnerability curves are used to obtain the probability of building damage. The number of victims is calculated based on the level of building damage using the event tree model from the HAZUS method. The results of the calculation show that the Lembang Fault earthquake with a magnitude of 6 could cause casualties in Coblong amounting to around 0.6% of the population, rising to as much as 1.5% for a magnitude of 7. The level of building damage is 36.6% and 55.6%, respectively.
Prediction of potential fishing zones for mackerel tuna (Euthynnus sp) in Bali Strait using remotely sensed data
Authors: Syah Achmad Fachruddin , Ramdani Laras Wulan , Suniada Komang Iwan
Published: July 2020

Mackerel tuna (Euthynnus sp.) is one of the pelagic fish species that has become the export commodity of Indonesia. This species is a carnivorous marine biota that forms a group with rapid swimming abilities. Mackerel tuna is scattered throughout Indonesian waters, including the waters of the Bali Strait. This study aims to predict Mackerel tuna fishing zone in the Bali Strait by using remotely sensed data. Sea surface temperature (SST) and sea surface chlorophyll-a (chl-a) were downloaded from the ocean colour website meanwhile the fishing catches obtained from nusantara fisheries port (pelabuhan perikanan nusantara) Pangembangan, Bali and the fishing lane from marine research and observation agency (balai riset dan observasi laut), Bali. The results showed that the highest of fishing catches occurred in September and October with SST value of 26 – 28 °C and chl-a value of 0.4 – 2.6 mg/m3. Based on the SST and chl-a value, the results revealed the potential fishing zone of Mackerel tuna mostly occurred during south monsoon (April - September). In general, the distribution of Mackerel tuna, based on the overlaid SST and chl-a, showed moderate spatial correlation with actual fishing locations from local fisherman. Integration in situ data and oceanographic condition generated from remotely sensed data could form the basis for fisheries management and information system, such as Mackerel in Bali Strait.
The development of WebGIS for the cultural sites in Kotagede Sub-District combined with 360° photosphere visualization
Authors: Ni Luh Kompyang S , Cahyono Bambang Kun , Laksono Dany Puguh , Djurdjani  , Riyadi Gondang
Published: July 2020

Kotagede is one of sub-districts in the Special Region of Yogyakarta which has several potentials especially in the cultural tourism industry. Long time ago, it was being the capital of Mataram Islam Kingdom. As a center of The Kingdom, Kotagede becomes one of the most important historical tourist spots in Yogyakarta. It is also a heritage city with great potentials to support the prosperity of its residents. The cultural site in Kotagede could be presented in the form of web based Geographical Information System (GIS) related to the spatial aspects, also by combining with 360° photosphere as its dynamic visualization. This WebGIS was made by integrating Google Camera, ArcGIS Online, ArcGIS Desktop, Pannellum website, and Cloudinary website. Usability testing was conducted with the System Usability Scale (SUS) as the testing instrument. Cultural site information in the WebGIS can be displayed in the form of an online map included widgets and other various functions in order to make it easier to be explored.
Spatial analysis of rice phenology using Sentinel-2 and UAV in Parakan Salak, Sukabumi Regency
Authors: Rokhmatuloh  , Supriatna  , Wibowo A , Shidiq IPA , Pin TG , Hernina R
Published: July 2020

West Java is the third province with the largest area of paddy field. On the province scale, there are five districts with more than 60,000 hectares of the paddy field area. Sukabumi is fifth largest districts with 6.8% of the area covered with paddy field. Although it is not the greatest number, Sukabumi is the largest producer of paddy with more than 6 ton per hectare, especially in 2011. Rice is the primary food for most of Indonesian. Therefore, monitoring the rice planting regarding the phenology, planting area, and productivity is a critical process. Information from the process is very important to address the national issue of food security. This study aims to generate spatial and temporal information on rice phenology. This study uses the excellence of remote sensing technology to cover a big area of paddy field. Sentinel-2 imageries and photos from Unmanned Aerial Vehicle (UAV) are being applied to generate Normalized Difference Vegetation Index (NDVI). With NDVI, this study determines the growth stage of paddy by discriminating each stage based on the spectral value. The planting phases that have discovered in the area are land preparation, vegetative, generative, and harvesting. Based on the NDVI value, it is known that the vegetative stage ranges from 0.181 to 0.80. The study concludes that result from Sentinel-2 and UAV can be used to show the distribution of paddy based on different growth stage.
Integrated ecological index (IEI) for urban ecological status based on remote sensing data: a study at Semarang – Indonesia
Authors: Indrawati Like , Sigit Heru Murti B S , Rachmawati Rini
Published: July 2020

The sustainability of a city will be greatly influenced by its urban ecological status. Remote sensing technology is very supportive for understanding the urban ecological status with advantages in terms of timely, precise and objective, so that has become an increasing concern in the world. In this paper, urban ecological status of Semarang city was analysed by an image of Landsat-8 OLI was acquired in a different season. The urban ecological status is integrated by two main components that are assumed that forming urban land, that is the primary land surface component (i.e. built-up area and vegetation area) and the climate (i.e. land surface humidity and dryness degree). These components are divided into four indicators obtained from the transformation of remote sensing data, which is the NDBI (normalized difference build-up index) for built areas representing the resident aggregation degree, SAVI (soil adjusted vegetation index) for greenness degree, NDMI (normalized difference moisture index) for land surface moisture and NDSI (normalized difference soil index) for the dryness degree. Principal component analysis (PCA) was utilized to compress the four indicators into one to construct the index for assessing overall urban ecological status. The results showed that there were differences in the urban ecological status in different seasons. Urban ecological conditions in the dry season are more varied than in the rainy season. Overall urban ecological conditions in the rainy season are better than the dry season.
Spatial distribution of PM10 derived from Landsat 8 imagery in Bandung, Indonesia
Authors: Hernawati R , Darmawan S
Published: July 2020

Air pollutant of PM10 concentration over Bandung City was estimated based on satellite imagery. The imagery was acquired by Landsat -8 on 22nd May 2019. The methodology implementation were started with pre-processing includes geometric correction, radiometric calibration to converted of digital number into surface reflectance values to estimated PM10 concentration. For calculated the algorithm of PM10 need the coeficient aerosol optical depth (AOD) was using from AERONET. The results showed that the estimation of PM10 distribution through satellite imagery in Bandung in the year of 2019 in average 36.18 μg/m3. According to Air Pollution Standard Index from that average Bandung city is still in healthy category of PM10 concentration. The calculated data on PM10 were also compared with ground measurements of PM10 data estimated from different locations of Bandung for validation and a linear relationship was established between them having a moderate positive relationship with the correlation coefficient value of 0.6187.
Correlation of PM2.5 based on Landsat 8 satellite imagery with ground measurements in Bandung City
Authors: Hernawati R , Darmawan S
Published: July 2020

The purpose of this research is to find the correlation of PM2.5 with ground measurements. The calculated of PM2.5 were using the algorithm derived from Landsat imagery in the year of 2019 and the concentration of PM2.5 ground measurements was collected using tools of sensor pocket PM2.5. The Implementation of methodology were include geometric and radiometric correction, calculation for PM2.5 algorithm inlcude AOD from AERONET, calculated LST, and calculated TVDI. The calculated data on PM2.5 were compared with ground measurements of PM2.5 from different locations in Bandung and the result show that a linear correlation of PM2.5 derived from Landsat between ground measurements having coefficient of determination value is 0.65 It means, the data of PM2.5 derived from Landsat 8 imagery between the data of PM2.5 ground measurements indicates a moderate positive correlation with linear regression model y = 0.8023x+3.8578.
Land use change mapping and its impact on storm water runoff using Remote sensing and GIS: a case study of Mumbai, India
Authors: Sansare Darshan A. , Mhaske Sumedh Y.
Published: July 2020

The rapid increase in urbanization worldwide has induced a change in land use–land cover (LULC) over the years. In Mumbai, India, this has further altered the hydrological processes like infiltration, evapotranspiration, interception and erosion and also caused loss of current drainage capacity and flooding in urban areas. This paper mainly assesses the changes in land-use land-cover types and its impact on storm water discharge from 1973 to 2018 in Mumbai using ArcGIS software. The image was classified into five LULC categories after superimposing in Arch-GIS, such as forest, open land, wetland, water and built-up area. The analysis of LULC pattern for the area under study over a period of 45 years showed that there was 66% rise in the built-up area whereas the Forest, open land and Wetland and water body together had reduced by 21%, 36% and 28%, respectively with respect to overall catchment area of Mumbai. Also, the analysis results gave a rise in peak discharge of storm water by 36% because of the changes in LULC over the given time period. On the whole, the land area affected by water logging has significantly increased over the time. The study therefore indicates that the integration of GIS and remote sensing was an effective way of approach for assessing the process of land-use land-cover change.
Analyzing mangrove forest area changes in coastal zone of Langsa City using landsat imagery
Authors: Suciani A , Rahmadi M T , Islami Z R
Published: July 2020

Mangrove forest is the most well known in Langsa City. Mangrove forest has high productivity and rich of biodiversity. However, the mangrove area has decreased in quantity. It caused by human activities (anthropogenic factors) and natural conditions. Aims of this research are to map the spatial distribution of mangrove forest in Langsa City, analyze the changes occurring mangrove area, and identify the factors that leading to the changes. Landsat 5 and Landsat 8 OLI images are selected to represent data with multi temporal images (1996, 2006, 2016, and 2018). This study used the maximum likelihood classification on multispectral data. The result of the research showed the accuracy of Landsat 8 OLI images in 2018 was 62.50%. Mangrove area changes during three periods of observed data, i.ehas decreased to 419.04 ha in 1996-2006, increase to 459.76 ha in 2006-2016, and decreased 330.57 ha in 2016-2018. These changes were generally caused by anthropogenic factors such as logging, garbage buildup, over function of mangrove to café, bridge and settlement. On the other hand, natural factors did not caused the change. Natural factors value in research location are accepted by mangrove growth requirements, i.e water pH was 7.8, temperature was 34°C, salinity was 33.03, and DO (Dissolved Oxygen) was 5.28.
Above-ground carbon stock estimates of rubber (hevea brasiliensis) using Sentinel 2A imagery: a case study in rubber plantation of PTPN IX Kebun Getas and Kebun Ngobo, Semarang Regency
Authors: Pratama Lalu Deden Yuda , Danoedoro Projo
Published: July 2020

Carbon stock estimates are very important to support carbon policies at the regional level and sustainable environmental management. Rubber plantation is one of the carbon-absorbing ecosystems, due to its long life and large biomass content. The aim of this study was to estimate the above-ground carbon stock based on Sentinel 2A remotely sensed imagery, through vegetation index approaches. In the initial stage, the image was corrected radiometrically to obtain a bottom of atmosphere (BoA) reflectance values, so that all spectral indices that were run could provide reliable results. The vegetation indices used in this study were RVI (Ratio Vegetation Index), NDVI (Normalised Difference Vegetation Index), ARVI (Atmospheric Resistant Vegetation Index), and SARVI (Soil and Atmospherically Resistant Vegetation Index). The values generated from those indices were correlated with field data of carbon stock, which was derived from breast height diameter (BHD)-based biomass measurements and allometric equations. Correlation and regression analyses of carbon stock and vegetation indices were then used to interpolate the samples to the entire study area, using exponential, logarithmic, and quadratic equations. The resultant above ground carbon stock maps were then tested for accuracy assessment using field data collected independently. It was found that the ARVI-based estimation model with BoA reflectance radiometric correction, combined with exponential regression equation, showed the best accuracy values of 84.48% (supported by r2 = 0.473). Based on this model, the above-ground carbon stock estimate in Ngobo and Getas Plantation, PTPN IX were 527,072.39 tons in an area of 2,656,615 hectares, or 198.4 tons/hectares.
Rainfall distribution in relation to flooding in upper Citarum watershed, Indonesia
Authors: Hanifa Syifa , Tambunan Mangapul Parlindungan , Marko Kuswantoro
Published: July 2020

Disasters caused by weather, such as flood, have become more frequent since the late 1990s. Compared to the previous decade, there are more than twice the number of floods in the world. Essentially, flood often occurs in lowland area with compact river systems. Unlike the case that often happened in the area around the Upper Citarum Watershed, floods occur because of the physical characteristics of the basin in the bowl-like form. In addition, rain that occur consecutively for a certain period of time in a day can result a surplus runoff water falling to the surface of the earth. Observation of rainfall has actually been carried out quantitatively since the 19th century. Satellite-based rainfall observation has the main advantage of being quite accurate in spatial and temporal coverage. This research is intended to see the pattern of rainfall distribution in relation to flooding in the Upper Citarum Watershed using remote sensing methods to process satellite images of PERSIANN CCS in obtaining rainfall data in each sub-watershed. Spatial results show six areas of rainfall distribution as of sub-watershed. Meanwhile, temporal results are analyzed with a graph that shows the pattern of hourly rainfall behaviour.
Object detection of aerial image using mask-region convolutional neural network (mask R-CNN)
Authors: Musyarofah  , Schmidt Valentina , Kada Martin
Published: July 2020

The most fundamental task in remote sensing data processing and analysis is object detection. It plays an important role in classification and very useful for various applications such as forestry, urban planning, agriculture, land use and land cover mapping, etc. However, it has many challenges to find an appropriate method due to many variations in the appearance of the object in image. The object may have occlusion, illumination, viewpoint variation, shadow, etc. Many object detection method has been researched and developed. Recently, the development of various machine learning-based methods for object detection has been increasing. Among of them are methods based on artificial neural network, deep learning and its derivatives. In this research, object detection method of aerial image by using mask-region convolutional neural network (mask-R CNN) is developed. The result shows that this method gives a significant accuracy by increasing the image training and epoch time.
Retention Pond and Pump Station as an Alternative To Flood Management In Bengawan Jero Irrigation Area
Authors: Harimurti Sabdoyono Wiyasa
Published: July 2020

Water is the source of life to all living organisms. But in a very large volume, water can be problematic to life. One of problems generated by a large volume of water is flood disaster. River, as a water source, is one of natural resources with multifunction to human beings. Some areas in Indonesia have increasing flood intensity as the rainy season comes. Retention pond and pump station is one solution to dealing with flood puddle occurring in area. One of areas experiencing flood routinely annually is Bengawan Jero Irrigation Area (D.I. Bengawan Jero). The design of retention pond and pump station in DI Bengawan Jero was calculated using flood flow rate with repeated period of 10 years. From the result of rainfall data processing with repeated period of 10 years using Nakayasu method, it could be found
Qplanngci of 7.37 m3/s at hour 1. The storage volume needed to deal with flood in the Retention Pond in Bengawan Jero Irrigation area is 3.909 m3, using 2 pumps with capacity of 2.5 m3/s. From hydrograph analysis, it could be concluded that the use of retention pond and pump station can control the peak flow rate by suppressing or cutting the flood peak to occur.
Using Baking Powder as Additional Concrete Material
Authors: Nugroho FK Budi , Sumarni S , Thamrin A G , Roemintoyo  , Isnantyo FD
Published: July 2020

Baking Powder is a useful ingredient for developing which basically used in increasing food volume. It is made from alkaline sodium bicarbonate elements, acid salts and corn starch. Baking powder is a chemical compound consisting of NaHCO3 formula. This compound belongs to the salt group and has been used for a long time. The main added ingredients of retarders are divided into several categories according to their chemical composition, including: 1) Lignosulphonic Acid and other salts, ie., Na, Ca or NH4, 2) Hydro-carboxylic acids and their salts. In this study we used baking powder as an added ingredient. This study aims at determining the setting time, compressive strength and the freshness of concrete with variations in the addition baking powder are 0.00%; 0.15%; 0.30%; 0.45% of the weight of cement. This is an experimental research. Test samples for compressive strength in the form of a concrete cylinder. The results showed that maximum value of compressive strength of concrete is in the addition of 0.45% baking powder with an increase in compressive strength of 6.43% of the nominal concrete.
Utility of local quartz powder and silica fume to produce high early strength of self compacting high strength concrete
Authors: Lisantono A , Susanto J B
Published: July 2020

Generally concrete needs 7 to 14 days to reach minimum adequate compressive strength. Sometimes it is needed to get high early compressive strength of concrete for some reason. This research conduct an experimental program to make high early strength of self compacting concrete which is using local quartz powder and silica fume. Twenty one cylinder specimens were made and tested to get the compressive strength at age of 1 day, 3 days, 7 days, 14 days, 21 days, and 28 days. While the modulus elasticity of concrete were tested only at the age of 28 days. The cylinder specimen was using standard size of (150 × 300) mm2. The experimental program shows that the average compressive strength of concrete in 1 day, 3 days, 7 days, 14 days, 21 days, and 28 days were 10.00 MPa, 27.16 MPa, 36.41 MPa, 40.93 MPa, 50.36 MPa, and 48.66 MPa, respectively. While the average modulus elasticity of the concrete at the age of 28 days was 18,703.45 MPa.
Effect of Water Content on the Characteristics of Bagasse Ash-Calcium Carbide Residue Stabilized Organic Soil
Authors: Hatmoko J , Handoko L
Published: July 2020

Research about chemically stabilized organic soil to improve shear strength has been done by many researchers. However, they have never undertaken the research about the the effect of water content on physical and chemical characteristics of stabilized organic soil. A set of experimental program performed in this research were chemical composition of organic soil (OS), calcium carbide residue (CCR), and bagasse ash (BA); also the physical characteristics of OS. The admixture (60% CCR + 40% BA) was added to the soil with proportion 5, 10, 15, 20, 25 and 30% with various water content, and the samples were cured in 7, 14, 21, and 36 days-curing time. Then, the experiment of physical properties of the stabilized soil was undertaken. The physical characteristics of the stabilized soil change with respect to the water content, quantity of admixture and the curing times. On the high water content, the changes of the physical properties are more significant compared to that on the lower water content. The unit weight, specific gravity, and the degree of acidity increase whereas void ratio and organic content decrease according to the proportion of the admixtures and curing time.
Constructing hydrotalcite Mg-Al-CÜ3 by utilizing CO32-’ from natural resource
Authors: Mahardiani L , Saputro S , Arinda R , Astuti Y F
Published: July 2020

This research aims to construct hydrotalcite Mg-Al-CO3 by tuning the pH synthesis and molar ratio. The tuning was carried out by applying different synthesis pH. In addition, utilization of snail shell waste is expected to replace CO3
2- ion that needed for anion component in hydrotalcite production. For this study precipitation and hydrothermal methods were applied for synthesis. The precipitation had been carried out in three steps, namely isolation of ion CO3
2- from snail shell, preparation of Na2CO3 solution using snail shell powder as ion CO3
2- source and synthesizing hydrotalcite, where hydrothermal method was carried out at 150 °C. Confirmation of hydrotalcite obtained was done using SEM and FTIR.
Simple synthesis of rGO (reduced graphene oxide) by thermal reduction of GO (graphene oxide)
Authors: Hidayat R , Wahyuningsih S , Ramelan AH
Published: July 2020

The rGO has been synthesized successfully by combination of modified Hummers method and thermal reduction. First, the GO was synthesized by modified Hummers method (chemical exfoliation) of graphite flake. This reaction obtained graphite oxide (GrO) as intermediate material. The materials were characterized by FTIR, XRD, TG/DTA and SEM. The FTIR data shows the functional group of graphite, GrO, GO and rGO, while XRD data shows crystal parameter of them. The TG/DTA was used to study the rGO formation at various of temperature (200, 300 and 400 °C). The rGO had carbonyl, carboxyl, hydroxyl and alkene functional groups and 2 theta peak at around 25° corresponds to [002] plane. The rGO layer by thermal reduction of GO had wrinkle sheets structure from SEM image appearance. In this result, the simple thermal reduction strategy of rGO is possible to control functional group and layer number depends on its application.
Freundlich Adsorption Isotherm in the Perspective of Chemical Kinetics (III): Isolation Method Approach
Authors: Patiha  , Firdaus M , Wahyuningsih S , Rahmawati F , Kusumaningsih T
Published: July 2020

Determination of Freundlich Adsorption Isotherm (FAI) fitting-constant is mostly carried out using different amounts of adsorbent with fixed amount of adsorbates, calculated for 1 g or 1 mgr, and measured at the same contact time. This technique is used together with Langmuir Adsorption Isotherm (LAI). It is considered empirical but, kinetically, it is similar to the Isolation Method (IM). The purpose of this study is to provide a theoretical basis for the use of the IM approach in conjunction with LAI based for FAI fitting-constant determination and provide suggestions for data analysis techniques. The study was carried out theoretically, while the validity test was carried out by applying the findings to the literature data which were supplemented by statistical tests. The results show that the present technique is somewhat dubious. The technique is not suitable for every adsorbent-adsorbate pair (violating the basic assumptions of the LAI kinetics aspect) and the non-linear analysis technique give an order-reaction that is not always consistent with the adsorption condition. A new technique has been introduced. This new technique gives a value of b = n (Percentage Difference, PD, is less than 5%).
Phase characterization and electrical properties of fluorhydroxyapatite : influence of molarity variation and microwave irradiation
Authors: Kubro Z S , Dahlan K , Wahyudi S T
Published: July 2020

Hydroxyapatite is one of the calcium phosphates that is most often used to repair tissue hard as teeth and bones due to its excellent osteoconductive properties and bioactivity, but hydroxyapatite has low chemical stability at high temperatures, high dissolution values in the biological environment and low resistance to damage in acidic environments. The addition of fluorine to hydroxyapatite can make hydroxyapatite have superior mechanical properties because of its higher thermal stability. It also can increase calcium phosphate mineralization and crystallization in the process of forming teeth and bones. This research was carried out by synthesis of fluorhydroxyapatite using microwave irradiation-assisted precipitation method, by varying the molarity ratio and the microwave irradiation used. The XRD results show that samples at high microwave irradiation (100P) both in molarity variations of [P]/[F] 4 and 6, fluorhydroxyapatite has the least impurity intensity and the highest fluorhydroxyapatite intensity among the others. FTIR analysis also shows that all samples have the same group and fluorhydroxyapatite has been formed which is shown in the OH…F functional group at wave number 3539-3544 cm−1. Microwave irradiation and molarity ratio [P]/[F] showed no relationship with conductivity value of fluorhydroxyapatite.
Adsorption of Pb(II) ion using pectin membrane
Authors: Hastuti B , Hadi S
Published: July 2020

Disposal of heavy metal ion into body waters may result in the disruption of aquatic biota ecosystem, thus needs to be overcome. In this study, a cellulose-based adsorbent membranes was developed as adsorbents of Pb ion. The membrane was prepared by mixing chitosan gel in 2,5% acetic acid solution with pectin gel in water for 3 h. The solution then was printed out into a polypropylene container and dried. The membrane characterization was performed using FTIR for functional groups identification, and XRD and SEM for physical characteristic analysis. The results showed the stability and resistance of the pectin membrane in acidic environment. FTIR data confirmed main functional groups that participated in the adsorption process included carboxyl and hydrogen. The XRD data show that the adsorbent has an amorf phase. Furthermore, a solid structure of the adsorbent was showed by SEM data. Adsorption of pectin membranes to Pb (II) ions reaches a maximum at pH 4, an optimum time of 60 min with an adsorption capacity of 92.68% and 92%, respectively. Furthermore, the pectin membrane in adsorbing Pb (II) ions follows the Freundlich isotherm.
Preparation of Ni/Zeolite as esterification catalyst in biodiesel production based on off-grade crude palm oil
Authors: Mazlan  , Lestari W A , Istiqomah A , Krisdiyanto D , Afrianto A W
Published: July 2020

This aim of this research is preparation to prepare catalyst of 0% Ni/Zeolite, 5% Ni/Zeolite, and 10% Ni/Zeolite. Catalyst of Ni/Zeolite was prepared by impregnation method. Biodiesel production was conducted by 2 steps, the first step was esterification using 3 types of catalyst 0% Ni/Zeolite, 5% Ni/Zeolite, and 10% Ni/Zeolite. The second step was trans-esterification using NaOH catalyst. The catalyst were characterized by FTIR to identify functional group and XRD to identify crystallinity. The acidity of catalyst was determined by ammonia adsorption. The catalyst can reduce FFA content in CPO that influence increasing of yield biodiesel production. The formation of biodiesel was confirmed by the GCMS analysis that identified the methyl ester produced. The highest yield of biodiesel production was obtained using 5% Ni/Zeolite catalyst. Based on physical analysis of biodiesel which includes density, acid number, and water content, biodiesel synthesized from palm oil off grade has qualified the Indonesian National Standard for biodiesel.
Synthesis, characterization and biodiesel conversion of monodispersed sulfonated-silica nanoparticles
Authors: Lestari W A , Saputra O A , Pramono E , Chaniago A P
Published: July 2020

The enhancing need of energy followed by increasing of human population to be main factors in fuels depleting. This motivated researcher over the world to solve and to utilize natural resources as bioenergy for human sustainability in future. Today, there are numerous research related to bioconversion and bioprocessing of natural resources as well as optimizing catalyst in biodiesel conversion. Design of suitable catalyst for biodiesel conversion to be a challenge in this research area. In this paper, we report of preparation, characterization and biodiesel conversion ability of heterogeneous catalyst, so called monodispersion sulfonated-silica nanoparticles (MSN). This nanoparticles was characterized by FTIR, TEM, SEM and SEM-EDAX as well as N2 adsorption-desorption. The result revealed that the catalyst prepared through CTAB templating technique has been successfully synthesized with high monodispersion nano-size. Moreover, its ability in biodiesel conversion up to 13.33% for purity percentage.
Effects of HSQ4 Concentration into dyes of Carica Papaya on the Performance of Dye-Sensitized Solar Cell
Authors: Supriyanto Agus , Ina Pote Fernince , Ramelan A. H. , Nurosyid Fahru , Wahyuningsih Sayekti
Published: July 2020

Organic dyes are very important in improving the performance of solar cells, at very low prices and friendly to the environment. DN-F15 transparent green is a squaraine dye with good stability on DSSC or with an alternative name HSQ4. HSQ4 is a synthetic dye that is very expensive, but sensitive to light so that it can improve the performance of solar cells. DSSC uses titanium dioxide (TiO2) as a semiconductor, electrodes are used as substrates for the flow of electric charge. DN-EP01 is a thixotropic terpineol-based screen-printable Pt paste with a viscosity of 4-7 Pa.s at 10s−1. In furnaces around 450°C will produce an even and transparent platinum particle layer which has high catalytic activity. The color of the platinum paste is straw or light yellow. Measurement of absorbance dyes solution using a spectrophotometer with a wavelength of 400 nm -800 nm. Characterization of I-VDSSC Carica Papaya produced a V
ocvalue of 560 mV, Isc
1.5 x 10−4 A, fill factor 0.47 and efficiency of 0.43%. After doping with HSQ4 the concentration of 1 resulted in a Voc
value of 378 mV, Isc
4.0 x 10−4
A, fill factor 0.49 and efficiency of 0.14%. An increase in efficiency in variation 3 is 0.24% and variation 5 is 0.35%, this shows the effect of HSQ4 concentration on the coloring of papaya leaf extract can improve the performance of DSSC.
Synthesis N doped TÍO2/PTFE by solvothermal method and their self cleaning performance
Authors: Aini F N , Hastuti S , Wahyuningsih S
Published: July 2020

Nitrogen-doped TiO2/PTFE with unique characteristic and photocatalytic self cleaning activity under visible light were successfully produced using a modified solvothermal method with urea as the nitrogen source. This study combines photocatalyst of inorganic materials (TiO2) with superhydrophobic polymers (PTFE) for self cleaning glass coating. The X-Ray Diffraction show that the composite crystalline and new peak formed as indicated of PTFE. FTIR showed the presence of C-F groups on N doped TiO2, which showed the composite had successfully formed. The morphology by scanning electron microscopy showed that agglomeration formed from N doped TiO2/PTFE. The composite coatings showed a contact angle of 111.4 °. The results confirm that the synthesized TiO2 were successfully doped with nitrogen and composite with PTFE, allowing a higher photocatalytic activity. The composite N doped TiO2/PTFE has competely coated on a glass substrate and enable to degrade methylene blue up to 79.9% for 1 hour irradiation.
Slow pyrolysis of coconut wood (Cocos nucifera L.) and bio-char compositions
Authors: Pranoto  , Widjonarko D M , Rafidah S , Elmatiana E
Published: July 2020

Biomass in the form of coconut wood (Cocos nucifera L.) was pyrolysed in an externally heated batch reactor. In order to determine the lignin, cellulose and hemicellulose content was used a Van Soest method as reference method. The effects of final temperature and heating rate on the yields and compositions of the bio-char were investigated. Pyrolysis runs were performed using reactor temperatures were 375 °C, 475 °C and 575 °C with heating rates of 5 min−1, 10 min−1 and 20 min−1. The bio-char yields were significantly influenced by the process conditions. The result showed that the bio-char mass decreased with increasing the final temperature, but increased with the increase of heating rate. The activation energy increases with increasing final temperature and heating rate. While the highest activation energy was 38.89 kJ mol−1 and the obtained on bio-char product amounted to 6858.84 cal/g at the final temperature 575 °C and heating rate 5 min−1. It was characterized by Fourier transform infrared spectroscopy. This study showed that FTIR spectra have the potential to be an important source of information for a quick evaluation of the chemical composition of coconut wood (Cocos nucifera L.).
The effect of temperature on lignin purification from bioethanol production waste based on palm oil empty fruit bunch
Authors: Lestari W A , Utami M R , Istiqomah A , Setiawan A H
Published: July 2020

In this study, the optimal condition of lignin purification from bioethanol production waste based on palm oil empty fruit bunch has been conducted. Purification of Lignin through two steps are impurities precipitation in pH 7 and lignin purification in pH 2 simultaneously with variation temperature. The concentration of lignin determines by spectrophotometer UV-Vis and thermal analysis to determine the ratio of lignin content and residual content. It was found that in lignin purification step, the lowest lignin concentration is at temperature 30°C with the concentration of lignin is 8.388% and the highest residual content is at temperature 60°C with % residual combustion is 26.652%. The optimal temperature at pH 2 for lignin purification is 50 °C with a lignin concentration is 73.854% and the residual combustion is 27.956%.
Optimizing antioxidant substances extraction produced by Holothuria atra using ultrasonic with response surface method
Authors: Murniasih T , Muthi’ah  , Widjanarko S B
Published: July 2020

This study was to discover the effect of ultrasonic extraction based on the factors of extraction time and amplitude, to increase the yield recovery of H. atra extract and antioxidant activity (IC50). The process in optimizing ultrasonic extraction was performed using Response Surface Methodology (RSM) with Central Composite Design (CCD). H. atra extract produced by the 2 different extraction methods indicated a significant difference in yield (maceration 5.48%, ultrasonic 10.43%) and antioxidant activity (maceration 149.38 ppm, ultrasonic 84.85 ppm). The antibacterial activity against B. subtilis, E. coli, and S. aureus), also the toxicity LC50 at 457.77: 443.63 ppm were not significantly difference. It was found that ultrasonic extraction method needs shorter time with higher yield and more antioxidant activity. The sea cucumber extract that was produced from the ultrasonic method contains alkaloid, triterpenoid, and saponin, while steroid undetected, and from the maceration method contains no alkaloid and steroid.
Wound healing activity of skin incision and skin burn from spray gel formula contains combination of banana stem (Musa acuminata Colla) and Aloe vera ethanol extracts on mice
Authors: Kundarto W , Pangesti K A Y , Shabrina F , Sasongko H
Published: July 2020

Various studies reports the activity of wound healing from banana stem (Musa species) and alsoAloe veraindividually. This research purpose are to identify the wound healing activity of skin incision and skin burn animal model from spray gel formula contains combination ofMusa paradisiacaColla andAloe veraL ethanol extracts on mice. This research were used randomized post test only control group design. Each of incision wound and burn wound models were used 28 mice and divided into 7 group. Group I was given with banana stem extract (BSE) 10%. Group II was given withAloe veraextract (AVE) 10%. Group III was given with 7,5% BSE and 2,5% AVE. Group IV was given with 5% BSE and 5% AVE. Group V was given with 2,5% BSE and 7,5% AVE. Group VI and group VII (povidone iodine) as vehicle and positive control respectively. All group were sprayed twice a day from first day until seventh day after skin incision/burn induction, and length of wound/wound diameter were observed everyday. The result showed that combination of BSE and AVE had wound healing activity in both wound model which did not different significantly compared with individual extract.
The effect of heat treatment on antioxidant activity of ethyl acetate extracts Arbila beans from Kapan, East Nusa Tenggara
Authors: Funome H , Pangastuti A , Setyaningsih R
Published: July 2020

Oxidative stress is a condition of imbalance between free radicals and antioxidants in the body. This condition is dangerous because free radicals easily react with biomolecules such as DNA and protein, causing damage. This oxidative stress can be prevented by intake of antioxidants in food or supplements. Arbila beans (Phaseolus lunatus L.) is a bean species that grows in East Timor and had been utilized by the local community from a long time ago. This research was aimed to analyze the antioxidant activity of Arbila bean ethyl acetate extract. The results of the research showed that antioxidants activity, which was expressed in IC50 value, was detected on the ethyl acetate extract of Arbila bean which is not cooked or cooked. The IC50 value of dry extract (LKE) and cooked extract (LRE) were 197.61 μg/mL and 207.93 μg/mL. Based on qualitative with HPLC, dry extract has 10 compounds and after given heat treatment is reduced to 6 compunds.
Microencapsulation of riboflavin (vitamin B2) using alginate and chitosan : effect of alginate and chitosan concentration upon encapsulation efficiency
Authors: Danarto YC. , Rochmadi  , Budhijanto
Published: July 2020

Riboflavin (Vitamin B2) plays an important role in the human tissue development, the production of red blood cells and helps release energy by breaking down proteins, fats and carbohydrates. Riboflavin cannot be produced the human body therefore must be supplied outside via dairy food. Riboflavin is very sensitive and unstable to environmental influence such as light and reduction agent. One of technology for maintaining the stability of riboflavin is microencapsulation which is composed of polymer matrix containing riboflavin. Na-alginate was chosen because it has properties such as biodegradable, biocompatibility, and non-toxic. Na-alginate also has a high loading capacity of riboflavin but Na-alginate is also easy to release riboflavin. Solving this issue, Na-alginate was coated with chitosan and the layer is then reinforced by crosslinking process with glutaraldehyde. The process of forming micro-sized particles was carried out by the emulsification ionic-gel method. This research aims to study the microencapsulation process of riboflavin with Na-alginate and chitosan. This research also studied the effect of Na-alginate and chiton concentrations upon encapsulation efficiency. The research showed that microencapsulation of riboflavin with alginate and chitosan can be done. The results showed that the Na-alginate and chitosan concentrations had an effect on the encapsulation efficiency. The increase in the concentration of alginate and chitosan will make the encapsulation efficiency higher until it finally reaches the optimum point. Encapsulation efficiency will drop past that point. The optimum point for Na-alginate and chitosan concentration are 3% and 2% respectively.