bluuebunny/crossref_metadata_2025_split huggingface dataset:
Remote sensing retrieval of chlorophyll-a concentration in the coastal waters of Hong Kong based on Landsat-8 OLI and Sentinel-2 MSI sensors
Authors: Dong Shundan , He Hongchang , Fu Bolin , Fan Donglin , Wang Taotao 
Published: February 2021

Abstract
Using Landsat-8 OLI remote sensing data and Sentinel-2 MSI remote sensing data as data sources, selecting the coastal waters of Hong Kong as the study area, using semi-analytical model as the method, selecting the same time as the measured chlorophyll-a concentration at the monitoring point and the cloud coverage rate of remote sensing images two types of remote sensing images with clear images less than 10%. For the two types of remote sensing images, two thirds of the remote sensing image data are selected after preprocessing, and the remote sensing reflectance of the monitoring point location corresponding to the actual date is extracted for correlation analysis, and the most relevant inversion factor is obtained for modeling. Meanwhile the remaining 1/3 of the data is used to test the accuracy of its inversional regression model. The best inversional regression model based on Landsat-8 remote sensing data is Y=6.8x2-20.77x+17.02, R2=0.906 which is slightly higher than the best inversional regression model based on Sentinel-2 remote sensing data Y=-3.345e +05x2+3826x-3.44, R2=0.801, which proves the feasibility of inverting the two types of remote sensing data for the chlorophyll-a concentration in the Hong Kong offshore waters, and the inversional results of the two types of data show that the chlorophyll-a concentration in the internal waters of the Hong Kong offshore waters is higher than the phenomenon of external chlorophyll-a concentration.
Interference identification and removal of seismic precursor observation data based on singular spectrum analysis method
Authors: Wang Xiao , Wang Yalu , Wang Jun , Huang Jingguo , Yu Dan , Ye Qing , Liu Gaochuan 
Published: February 2021

Abstract
The singular spectrum analysis (SSA) method has the characteristics that it is not affected by the noise spectrum distribution, and is superior to the traditional denoising method. Moreover, it has been commonly used in signal analysis in the fields of oceanography, machinery, and electronic technology. This paper systematically introduces the basic principle and implementation process of singular spectrum analysis method. Then the singular spectrum analysis method is applied to the interference identification and removal of seismic precursor observation data. Taking deformation data and geoelectric field observation data as an example, the results show that the singular spectrum analysis method can effectively separate the rainfall interference in deformation observation data, and has important guiding significance for the subsequent removal of rainfall interference. In addition, the singular spectrum analysis method can be used to extract and remove the interference of HVDC and subway from the geoelectric field observation data, and the effect is obvious, which can effectively improve the data quality and better serve the earthquake analysis and prediction.
Reform, application and challenges of utilizing big data in coal mine safety management research
Authors: Chen Xue , Qiao Wanguan 
Published: February 2021

Abstract
Big data greatly impact current social science research paradigms and traditional safety management. Moreover, widespread big data application in coal mine safety technology has also highlighted the lack of basic coal mine safety management review against the background of big data. Based on the above analysis, the three main article goals are (1) to study the fundamental safety management research changes within the big data context; (2) to analyze big data application in coal mine safety management; and (3) to discuss big data relevance in coal mine safety management development trends and challenges. In summary, integrating big data into coal mine safety management has become a research trend, and the current coal mine safety management theory in the field of big data requires more in-depth research.
The influence of change of land-use type on hydrological cycle
Authors: Xiaoyong Wang , Lihe Yin , Honglin MA , Zebing Dai , Jiaqiu Dong , Xueqin Zhang 
Published: February 2021

Abstract
Change of land-use pattern causes the change of underlying surface environment in the basin, thus influencing the source and sink of hydrological cycle in the study area and to greatly affect the groundwater level. In order to study the relationship between underlying surface change and groundwater level, this paper quantitatively analyzed the remote sensing images of the Hailiutu River basin acquired in different periods and collected long-series groundwater monitoring data, and this paper drew a groundwater level change map by calculating the transfer matrix of different land-use types. On this basis, this paper analyzed the groundwater level and influential factors for the transfer amount of different land-use types. Results showed that the change in groundwater level was mainly influenced by the underlying surface change. The land-use types exhibited strong tempo-spatial transformation. Where there was a drastic change of land-use type, there was a sharp change in groundwater level, indicating that the change of land-use type greatly influenced the underlying surface and was positively correlated with the spatial distribution of groundwater level.
Application of low-cost mesoporous geopolymer for dye waste removal
Authors: Fitriani Evi , Purbasari Aprilina 
Published: February 2021

Abstrak
Environmental pollution causes a significant reduction in water quality. Sustainable development and industrial waste pollution are the supporting factors for the amount of water that is not suitable for consumption. Contaminants in wastewater that pollute water sources include phenolic compounds, substituted compounds, various types of pesticides, and dyes. This study focuses on developing geopolymers as a low-cost alternative adsorbent for adsorbing harmful dyes. Geopolymers can rapidly absorb dyes due to their supportive surface properties to absorb dyes. The porous structure is derived from alumino-silicate materials such as kaolin, metakaolin, dolomite, fly ash, and slag which have been activated with alkaline or alkaline silicate solution. Geopolymers are readily stored adsorbents. Geopolymers have shown good adsorption capacity of the dyes of Methylene blue, Rhodamine B, Congo Red, Methyl Orange, Methyl Violet. This study aims to provide an overview of the types of geopolymer forming materials, geopolymer characterization, application of geopolymers as dye adsorbents, and comparison with other adsorbents. The adsorption isotherm model and adsorption kinetics are also summarized in this overview.
Adsorptive removal of methylene blue from aqueous solution onto koh-activated carbons derived from saba banana (m. Acuminata balbisiana) peel
Authors: Parmita Ade Wahyu Y P , Hartanti Ansita F B , Ernawati Lusi , Laksono romeda Dwi , Iskandar Zulkarnain M , Fadila Febryela Alda 
Published: February 2021

Abstract
Organic pollutants in water are an increasingly prominent problem. Given this challenge, this study reported the high adorptive removal of methylene blue (MB) onto potassium hydroxide (KOH)-activated carbon. To prepare activated carbon, saba banana peel that are local organic waste were carbonized at 400 ° C and activated using various KOH concentrations, e.g.(0,5, 1 and 1,5 M). Physical and microstructural properties of activated carbon were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), and Fourier Transform Infrared (FTIR). The efffect of KOH concentrations on the adsorption perfromance of MB on KOH-activated carbon were further investigated. The adsorption process occurred more easily after KOH (1,5 M) of concentration and the adsorption capacity of activated carbon improved by more than 23 %. These results indicate that preparing Banana fruit peels-derived activated carbon using KOH activation is an effective way to reduce pollution and utilize a waste resource.
Adsorption of Pb(II) from aqueous solution by acid-modified water hyacinth cellulose
Authors: Tsaniatri D A , Hargono H 
Published: February 2021

Abstract
Water hyacinth has high cellulose content so that its potential to increase the adsorption capacity of heavy metal. Besides has containing cellulose, water hyacinth also contains lignin, which can inhibit the adsorption process. Delignification of water hyacinth was conducted by NaOH so that the cellulose content in water hyacinth increases as the lignin decreases. The research aimed to study the effect of nitric acid-modified on Pb(II) adsorption capacity. The various nitric acid at 0.2, 0.6, and 1 M concentrations. The influence of pH, contact time, and initial metal ion concentration in the adsorption process was studied. The analysis of Pb(II) metal ion contents in a solution used Atomic Absorption Spectrometer (AAS). Results showed that the best of Pb2+ adsorption is water hyacinth cellulose adsorbent with nitric acid modification of 1 M (D) was 8.6403 mg/g. The lowest adsorption was observed at 99.8883% for Pb2+ ion at pH 4, while the highest adsorption was 99.9477% at pH 7. The optimum contact time for Pb2+ adsorption at 100 minutes. The amount of Pb2+ ions adsorbed enhancement with an increase in the initial metal ion concentration.
Enhanced wash-fastness of cotton fabric dyed with a composite of chitosan-natural dyes extract of Ceriops tagal
Authors: Kartini I , Halimah S N , Rahayuningsih E 
Published: February 2021

Abstract
Chitosan coating on dyed cotton fabric by the natural dye of Tingi (Ceriops tagal) has been done to improve the wash fastness. Hydrophobic coating using HDTMS (hexadecyltrimethoxysilane) was also introduced to obtain multifunctional textiles. Fabric dyeing was done by the dip-coating method in two ways, one-pot (Op) and layer-by-layer (LbL). Specular-reflectance (SR) UV-Vis spectrophotometer was used to access the dyeing quality. An infrared spectrophotometer evaluation was performed to indicate the possible interaction between chitosan and the dye on the dyed cotton fabrics. The leaching degree was determined by using sodium dodecyl sulfate (SDS) and lerak (Sapindus rarak) natural surfactant as the leaching agents. The results showed that LbL coating has shown better dye-coverage on the cotton fabrics compared to the Op coating. However, cotton fabric coated by chitosan/tingi (Op) showed better performance than that of the LbL, with a leaching degree of 6.2% on SDS leaching, and 4.1% on lerak’s leaching. While, for LbL coating, the leaching degree was 20.1% on SDS and 13.9% on lerak’s leaching. The hydrophobic coating was stable and not affected by leaching. Different types of molecular interaction between the dye and chitosan from different coating techniques may result in those different performances on leaching.
Fabrication and application of ZnO-Ag nanocomposite materials prepared by gas-phase methods
Authors: Kusdianto K , Sari T D , Laksono M A , Madhania S , Winardi S 
Published: February 2021

Abstract
Zinc oxide nanoparticles have been used in various applications because of its unique physical and chemical properties. Unfortunately, the performance of pristine ZnO is inhibited by electron-hole recombination. The zinc oxide performance can be improved by metal doping to enhance its properties. This review paper provides summary of the synthesis and application of zinc oxide doped by silver (Ag) using different synthesis via gas-phase methods. From this review, synthesis parameters that will affect the ZnO-Ag nanoparticle and its application will be concluded. The gas-phase synthesis methods include flame spray pyrolysis, spray pyrolysis, sputtering, plasma enhanced chemical vapor deposition, electron beam evaporation, atomic layer deposition and electrospinning. It is clearly observed that the morphology, crystallinity, and performance of ZnO-Ag nanocomposite is significantly affected by the fabrication method. The precursors used, spray rate, deposition rate, precursor concentration, deposition time, morphology of the nanoparticle and deposition or annealing temperature affect the performance capability of ZnO-Ag. We believe that this review paper will provide valuable information and new insights into possible fabrication methods of ZnO-Ag nanocomposite materials in the gas-phase, which can be used for many applications as photocatalyst, anti-microbial applications, catalyst for hydrogen production as well as in dye-sensitized solar cells and gas sensors.
ZnO-TiO2 nanocomposite materials: fabrication and its applications
Authors: Kusdianto K , Nugraha D F , Sekarnusa A , Madhania S , Machmudah S , Winardi S 
Published: February 2021

Abstract
Zinc oxide (ZnO) is one of the most commonly used semiconductor materials for various applications, namely as photocatalysts, gas sensors, antimicrobial substances, and photovoltaic cells. The performance of the particles is greatly influenced by the morphology and the optical properties of the particles itself. To improve the performance of ZnO, one method which can be applied is by doping support with other semiconductor materials, such as TiO2. This is caused by electron transfers between ZnO and TiO2 which are able to enhance the stability of ZnO and the electron mobility of TiO2. Therefore, the electron-hole recombination can be inhibited by this mechanism. Fabrication of ZnO-TiO2 can be prepared by several methods, which is gas or liquid phases and solid phase. Spray pyrolysis, chemical vapor deposition, micro-arc oxidation, electrospinning and electron beam evaporation are preparation method for gas-phase synthesis, while sol-gel, hydrothermal, precipitation, solution combustion, pulse plating, and wet impregnation are for liquid phases. In this study, the fabrication methods of ZnO-TiO2 and its application have been reviewed as well as the factors that affect the morphology, performance, and the stability of ZnO-TiO2 nanocomposite. This review is conducted by comparing the analysis results with their performances. It is clearly found that there is an optimum condition for obtaining the best photocatalytic performance by adjusting the ratio of ZnO to TiO2. Furthermore, ratio of ZnO:TiO2 concentration on antimicrobial activity shows a linear performance, and it is obviously observed that the ZnO- TiO2 nanocomposite shows a better performance compared to the pristine ZnO or TiO2 in various applications. We believe that this review will provide valuable information and new insights into possible fabrication methods of ZnO-TiO2 nanocomposite materials, which can be used in many applications.
Fabrication of High Performance PSf-rGO/TiO2 UF Membrane for Ruberry Wastewater Treatment
Authors: Kusworo T.D. , Wulandari Lutfi Mia 
Published: February 2021

Abstract
Membrane technology is commonly used because it is one of the most effective and efficient technologies in producing clean water. The PSf-rGO / TiO2 UF (Ultra Filtration) membrane was synthesized using the phase inversion NIPS method. The membrane was synthesized by modifying the membrane surface by adding rGO / TiO2 nanoparticles to achieve the best performance. The membrane matrix used wasthe polymer of Polysulfone (PSf) with 0, 0.5, 1, and 1.5 wt% nanoparticles addition and UV irradiation time of 0.5, 1, 3, and 5 minutes. The higher concentration addition of rGO / TiO2 at 1.5% resulted in the best permeability. Meanwhile, the UV irradiation time of 3 and 5 minutes were the lowest time to gain permeability value.
The effect of legen treatment on fermentation process in production of nata de legen
Authors: Hendrianie N , Putri S N , Satria Y I 
Published: February 2021

Abstract
Palmyra palm (Borassus flabellifer) is one of the most widely cultivated plants in Indonesia, especially in Gresik, East Java. The number of Palmyra palm trees in that area is estimated to be approximately 5,000,000. The Palmyra palm tree produces a large amount of legen obtained by tapping the palm flower and its use now is only limited as a beverage. By processing the legen into the nata, it would increase its selling price and the local people’s income. In this research, the method used to produce the nata de legen was by fermenting the legen using the microbial Acetobacter xylinum. This method was the same as for producing the nata de coco from coconut water. There were various methods of pre-treatment of the legen before the fermentation process. The legen was stored at room temperature 30°C, cooled in a refrigerator for 2 hours, or heated at 100°C for 10 minutes, with incubation time was 10 days respectively. The results showed that the quality of the nata de legen was affected by the pre-treatment of the legen. The best quality of the nata obtained was its thickness of the 4 mm and the cellulose content of 23.25% under pre-treatment condition at 100°C
POLY LACTIC ACID (PLA) DEVELOPMENT USING LACTIC ACID PRODUCT FROM RICE STRAW FERMENTATION WITH AZEOTROPIC POLYCONDENSATION PROCESS
Authors: maryanty Yanty , Hadiantoro Sigit , Widjajanti Kristina , Putri Dahniar Ika Kusuma , Nikmah Lailatul 
Published: February 2021

Abstract

Polylactic acid ( PLA) is the raw material for the manufacture of environmentally friendly plastics since microorganisms more easily destroy it in nature. PLA had made from renewable materials such as wood, such as agricultural waste, such as lignocellulose-containing rice straw. Azeotropic polycondensation method has been using for the processing of PLA. This method is relatively simple and can yield a high molecular weight of PLA. Xylene solvent had used to absorb water, and the SnCl2 catalyst has used to accelerate the reaction. The polymerization process lasts 30 hours. The results of the polymerization process were deposited with excess methanol and then filtered with a vacuum pump and then toasted at 800C within 2 hours, resulting in PLA crystals in the form of yellowish-white powder. The best condition is that the 40-gram mass variation produces PLA with a yield of 49.6 per cent PLA, a molecular weight of 57066.9 g / mol and a temperature melting of 120 ° C. The situation had used in the polymerization of fermented lactic acid after achieving the best conditions for the scientific lactic acid polymerization, namely at a lactic acid mass of 40 gr. PLA polymerized lactic acid fermented with rice straw has the characteristics of dark-grey powder with a molecular weight of 2310.86 g / mole and a temperature melting of 135 ° C.
Kinetics study of enzymatic hydrolysis of Tetraselmis chuii using Valjamae model
Authors: Megawati  , Damayanti A , Putri R D A , Sari P N , Fidyani D 
Published: February 2021

Abstract
The Tetraselmis chuii microalgae have a potential as an alternative raw material for producing bioethanol, because of its low lignin and high carbohydrate content. The purpose of this research is to study the kinetics of enzymatic hydrolysis of Tetraselmis chuii using Valjamae model. This experiment was carried out with a variety of enzymes (cellulase, xylanase, and cellulase-xylanase mixture, enzyme concentrations (10, 20, and 30% w/w), times (10, 20, 30, and 40 min), and temperatures (40 and 45 °C). The results show that the activation energy of hydrolysis using cellulase-xylanase mixture is 27,253 J/mol, xylanase 116,121J/mol, and cellulose 140,914 J/mol. At 45 °C, the concentration of the cellulase-xylanase mixture increased (10, 20, and 30% w/w), the reaction rate constants (0.028, 0.110, and 0.171 1/min) as well as the fractal exponents (0.4, 0.6, and 0.7). Thus, the glucose production rate is higher, where at 40 minutes produces higher yields (23.5, 25.5, 28.5, and 32.5%). In this study, the constant rate of Tetraselmis chuii hydrolysis using cellulase-xylanase mixture at 45 °C is 0.1714 1/min; higher than the one conducted at 40°C which is 0.1454 1/min. The kinetic parameters of the enzymatic hydrolysis are expected to help in bioreactor design.
Fermentation of Tapai and Alcohol Content Released From Tapai
Authors: ul-Haque Dr.Siti Noor Suzila Maqsood , Mueedin NurulSyazwani 
Published: February 2021

Abstract
Tapai is a well-known dessert with slight alcoholic flavour and a sweet sour aroma. Normally, glutinous rice and cassava roots are always used to make Tapa. Both of them are almost similar in taste. However, Tapai needs to be consumed immediately because it is a perishable product. So we need to preserve Tapai by using either natural or synthetic preservatives. In this study, we will review turmeric essential oil as natural preservative to preserve Tapai. If we let it to be fermented for too long, its alcohol content might increase and it may turns the Tapai becomes too alcoholic. So, this review study is conducted to study how to detect alcohol released from Tapai. Different research studies have been done on detecting alcohol released from Tapai by using different kind of methods such as specific-gravity method, refractive index and GC-MS methods. But this review article is focusing more on alcohol biosensor. Other than that, we will observe the changes in biochemical properties of Tapai such as pH and total lactic acid
Oxidation Models of Encapsulated Iron Using Alginate by Gelation Method
Authors: Wardhani D H , Ulya H N , Astuti W I S T , Kumoro A C , Aryanti N 
Published: February 2021

Abstract
Alginate had been used as an additive on many food materials due to its biodegradability and non-toxic properties. As the alginate was extracted from natural sources, it had various properties depending on its source and purification method. In general, alginate has high gelation which hinder its use in high concentration in specific applications. This work aimed to study the effect of alginate modification in protecting oxidation of iron. The modification was conducted using ultrasound. The degraded alginate was applied for encapsulating iron using gelation method. The oxidation profile of the iron was modelled. The result showed that the lower alginate concentration and longer ultrasonication process decreased the alginate ability on protecting the oxidation. After 15 days, the lowest oxidation (8.47%) was able to be suppressed by ultrasonication of 5 % alginate for 30 min. The Kirby model (R2>0.76) was more suitable in describing the oxidation rate from the iron encapsulated by the degraded alginate.
Biodiesel production process without glycerol by-product with base catalyst: effect of reaction time and type of catalyst on kinetic energy and solubility
Authors: Daryono E D , Wardana I N G , Cahyani C , Hamidi N 
Published: February 2021

Abstract
Biodiesel is a renewable energy that is very potential to be produced because it has many advantages compared to diesel fuel. The process of making biodiesel which has so far been carried out is a transesterification process with glycerol byproducts. Glycerol has a low economic value and is usually only disposed of as waste. An alternative process for producing biodiesel with more valuable byproducts is interesterification. The by-product of the interesterification reaction is triacetin which is widely used in the chemical, food and pharmaceutical industries. From the analysis and calculation, the highest FAME yield was 87.18% at reaction temperature 60&#x00B0;C, the molar ratio of palm oil: methyl acetate = 1: 6, reaction time 1 hour, NaOH catalyst, stirring speed of 400 rpm and catalyst mass of 0.5% wt. oil. From the calculation of ChemDraw software for the triglyceride + methyl acetate + NaOH system had an energy kinetic of 2930.8062 kcal/kmol and a dipole moment of 12582.9333 debye, whereas the triglyceride + methyl acetate + KOH system had a kinetic energy of 3140.9573 kcal/kmol and a dipole moment of 9630.3735 debye so that the NaOH catalyst is superior in solubility and the KOH catalyst is superior in reactivity. Biodiesel produced had an acid value of 0.224 mg KOH/g and meets ASTM D664 for a maximum acid value of 0.5 mg KOH/g, and a density of 0.888 g/ml so that meets ASTM D1298 for a density between 0.86 – 0.89 g/ml.