bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Titanium Dioxide (TiO2) Extraction Process from Ilmenite Banten
Authors: Ginting Lavita Indriani Br. , Manaf Azwar , Astuti Widi , Supriyatna Yayat Iman , Bahfie Fathan
Published: June 2023

Ilmenite is found in the form of iron sand with reserves of 927,315,827 tons spread across several regions in Indonesia, including Banten which has seven million tons of iron sand. This mineral can be used as a raw material for making TiO2 pigments. The problem faced in the use of Ilmenite is its complex mineral structure which causes difficulties at the processing stage. The synthesis of TiO2 from ilmenite ore commonly used the sulfate process and the chloride process. The sulfate process is less environmentally friendly, has excessive costs, and produces a lot of liquid waste. While the chloride process requires high-grade raw materials and requires chlorine gas. Therefore, in this study, the synthesis of TiO2 from ilmenite Banten using caustic fusion, acid leaching using hydrochloric acid, and the use of citric acid were conducted. Caustic fusion is conducted with ratio between ilmenite and NaOH is 1:2, with a fusion temperature of 850 °C and a fusion time of 60 minutes. Then next process is water leaching and acid leaching. The result of this study is that the TiO2 obtained from each acid leaching is hydrochloric acid leaching producing powder pigment with 94.189% TiO2, acetic acid leaching producing 37.099% TiO2, citric acid leaching producing 41.480% and hydrochloric acid leaching without fusion process producing 43.991% TiO2.
The carrageenan fermentation process for (L)-lactic acid production using Lactobacillus plantarum: effect of fermentation time
Authors: Hidawati  , Saraswaty V , Marganingrum D , Nissa R C , Abdullah A H D , Handayani S
Published: June 2023

The increase in plastic production has raised concerns about the depletion of fossil fuels. In addition, the environmental problems related to improper plastic waste have become progressively concerning. Polylactic acid (PLA) is one of the most intriguing biopolymers for the fabrication of biodegradable plastic. More importantly, PLA has sharply increased interest in producing its monomer, lactic acid (LA). Considering the expensive cost of LA production, exploring the potential of refined kappa-carrageenan (RKC) as a low-cost substrate is crucial. This work aimed to study RKC hydrolysate’s effect (20g L−1) on lactic acid production. A set of parameters were evaluated, including lactic acid content by high-performance liquid chromatography (HPLC) analysis, optimum bacterial growth, and reducing sugar content. The results showed that by utilizing RKC as the substrate, the growth of Lactobacillus plantarum reached its maximum within 24 hours of fermentation. The reduced sugar content decreased from 18.8 to 0.8 g L−1 after 72 hours of fermentation. More importantly, about 18.5 g L−1 of LA was produced. In conclusion, the present findings suggest that RKC can be potentially used as an alternative substrate for lowering LA production costs.
Physicochemical properties of sodium alginate from brown algae Sargassum aquifolium and Sargassum cinereum
Authors: Chaldun E R , Andayani D G S , Handayani T
Published: June 2023

Synthesis and characterization of sodium alginate from Sargassum aquifolium dan Sargassum cinereum have been successfully performed. S. aquifolium and S. cinereum were collected from the Dompu Islands, West Nusa Tenggara, Indonesia. Extraction was performed by acid pathway, due to cell disruption and the addition of Na2CO3 for extraction. The addition of HCl was to convert acid alginate into alginate, then transformed acid alginate into sodium alginate using NaOH. NaOCl and IPA were used for purification. Physicochemical properties were characterized using SEM-EDS, FTIR, and TG/DTG. The morphological structure of synthetic sodium alginate shows layer structure and fiber fibrils. Sodium alginate contained C, O, Na, and Cl elements. FTIR spectrum indicated the presence of functional groups at the following wavelengths: OH at 3343 cm−1, CH2 at 2915 cm−1, CO double bonds at 1614 cm−1, and fingerprint indicated by the presence of uronic acid, which functioned as the CH group stretched at 935 cm−1. The sodium alginate sample shows a three-step thermal degradation pattern. The first step was starting at 41.7 °C associated with dehydration and was followed by 206.4 and 241 °C associated with decomposition. TGA/DTG results showed a reduction in thermal stability at 250–300 °C. It is suitable for modification and application.
Characterization of microcrystalline cellulose from red seaweed Gracilaria verucosa and Eucheuma cottonii
Authors: Nissa R C , Abdullah A H D , Firdiana B , Kosasih W , Endah E S , Marliah S , Rahmat A , Hidayat
Published: June 2023

Microcrystalline cellulose (MCC) is pure cellulose isolated from alpha cellulose. The demand for renewable and sustainable raw materials for the industry has developed as one of the most pressing challenges in recent decades. The seaweed processing industry produces a large amount of solid fibrous waste, which can be utilized as an additional source of cellulose feedstock. The increase in seaweed production continues to increase, as well as waste that can be used as another source of cellulose raw materials. This study used red seaweed i.e., Gracilaria verucosa and Echeuma cottonii to produce high-quality MCC. Gracilaria verucosa and Echeuma cottonii are treated chemically through alkali, bleaching, and acid hydrolysis to obtain pure MCC. Following the X-ray diffraction (XRD) analysis result, MCC in the standard had a crystallinity of 67.2%, while the Gracilaria verucosa-MCC (GV-MCC) sample was 53.0% and Echeuma cottonii-MCC (EC-MCC) was 58.4%. Fourier transform infrared (FTIR) spectroscopy showed that GV-MCC and EC-MCC almost resemble the MCC standard. The morphology characteristic from Scanning electron microscope (SEM) analysis presented the difference between raw material before and after isolation into MCC. According to the Particle size analyzer (PSA) result, the mean sizes of EC-MCC and GV-MCC are 0.786 and 0.522 µm, respectively. The isolation of MCC from red seaweed has the potential to be used in a wide range of industries.
Implementation of drinking water quality surveillance and household water management practices in selected provinces in Indonesia
Authors: Irianti S , Yunianto A , Dharmayanti I , Hidayangsih P S , Zahra Z , Mbarep D P P , Sutapa I D A
Published: June 2023

Safely managed drinking water (SMDW) is a prerequisite for maintaining human health and well-being. Therefore, drinking water quality surveillance (DWQS) is an appropriate approach to achieve the targets of Sustainable Development Goal (SDG) 6, particularly the SMDW indicator as the highest ladder of drinking water services. The objective of this study was to elicit information on current DWQS and household drinking water management practices (HDWMP) in South Sumatera, West Java, South Kalimantan, and North Sulawesi Provinces. The methods included an in-depth interview with 35 informants and an interview with 175 households using a structured questionnaire. The results revealed that the DWQS did not fully comply with Health Ministerial Decree (HMD) No. 736/2010, particularly in dealing with sample size, the availability of reagents, comprehensive reports, and recommendations for remedial actions. Dealing with the HDMWP, 46.86% of households used piped water, followed by protected dug wells (30.29%), boreholes (12.00%), and refilled water (10.86%). Only 43.43% of household water sources were free from Escherichia coli, where these were dominated by urban households. The majority of households complied with the chemical quality of several parameters. The proportion of households with SMDW was 35.9% and it was much higher than that of the national level. As such, the improvement of drinking water surveillance is needed through the implementation of water safety plans.
Synthesis and Physical Characterization of Bioplastics Based on Jicama Starch (Pachyrhizur Erosus) – Chitosan
Authors: Kusumaningrum M , Imani NAC , Gemilang S , Rahma FN , Wulansarie R
Published: June 2023

The development of plastics that can be easily degraded is needed to reduce the impact of plastic use on the environment. This study aimed to utilize the starch present in jicama to be used as the main material for making plastic. In order to overcome the drawback of starch which is less flexible, materials such as chitosan and glycerol were used. The stages of this research consisted of extracting starch from jicama, making bioplastics by mixing yam starch with chitosan and glycerol in varying amounts, as well as analysis and characterization in the form of tensile strength tests, elongation measurements, hydrophobic properties measurements, and degradation tests. The results of the study showed that by varying the amount of glycerol and chitosan, the bioplastic degradation ability obtained could be optimized.
Potential Utilization of Sugarcane Bagasse as Raw Material for Bioethanol Production
Authors: Triyani A , Fachrul M F , Minarti A
Published: June 2023

Bagasse has the potential to generate alternative energy resources such as bioethanol owing to its lignocellulose structure. This research aims for utilizing bagasse as the raw material for producing bioethanol. The process for producing bioethanol consists of delignification, hydrolysis, fermentation and distillation using biocatalyst namely Fungi Dekkera bruxellensis and yeast Saccharomyces cerevisiae. Delignification was conducted at the substrate variation of 5, 10, 15 grams and 3, 5, 7 days contact time. The hydrolysis process used H2SO4 2% with 30, 45, 60 minutes contact time. Fermentation used concentration ratio for fungi and yeast at 1:1 with 3, 5, 7 days contact time. The distillation process went through the temperature of 78-80°C to obtain ethanol. The gravimetric analysis shows the optimum removal efficiency at 10.90% using 5 gram substrates with 3 days contact time. The hydrolysis process shows the highest glucose concentration at 16.64 g/L for each contact time using 15 gram substrates and H2SO4 2%. The highest amount of ethanol was 3.1% with the ratio of substrates 1:1 and 3 days contact time. This research shows that bagasse can produce bioethanol by the utilization of Fungi Dekkera bruxellensis and yeast Saccharomyces cerevisiae.
Characterization of Red Beans Yogurt (Phaseolus vulgaris L) with addition of dates (Phoenix dactylifera)
Authors: Damayanti Astrilia , Putri Radenrara Dewi Artanti , Salim Tobias Samuel , Sriwijaya Hannah Arya , Bajuri Dheandles Duta Agung
Published: June 2023

Yogurt is one of the probiotic products that is commonly consumed and widely developed across the world. This experiment aims to determine the effects of red beans, dates, and starter culture addition on a certain ratio of full cream milk powder and characterized by Indonesian National Standard also known as SNI number 2981 :2009. This experiment was conducted with the ratio of red beans to dates (v/v) were 40:60, 50:50, and 60:50 and the starter cultures (%v/v) were 5, 15, and 25. This experiment method consisted of making red beans juice, dates juice and fermentation. The results of the experiment showed that the protein content (%) of the ratio of red beans to dates (v/v) and starter cultures (%v/v) were 40:60 and 5, 50:50 and 5,60:40 and 5; 40:60 and 15, 50:50 and 15, 60:40 and 15; 40:60 and 25; 50:50 and 25, 60:40 and 25 were 3.455, 3.63, 3.335, 2.805, 2.965, 2.915, 2.305, 3.10, and 3.15. While the fat content (%) were 2.22, 2.015, 1.55, 1.58, 1.515, 1.28, 1.27, 2.20, and 1.655; and the ash content (%) were 0.795, 0.88, 0.855, 0.835, 0.855, 0.91, 0.78, 0.82, and 0.89. The protein content that was not in accordance with the SNI was only found in yogurt with a ratio of red beans to dates 60:40 (v/v) and starter cultures of 5 (%v/v). Yogurt made from red beans, dates, and addition of full cream milk powder has the potential to become a healthy drink with a new taste.
Kinetic study on hydrolysis of sweet sorghum (Sorghum bicolor (L.) Moench) stem dregs with cocktail enzymes in bioethanol production
Authors: Megawati  , Triwibowo B , Bahlawan Z A S , Fitriani Z , Ulfah N
Published: June 2023

Sweet sorghum stem dregs have potential as an alternative raw material for bioethanol production due to its high sugar content. The purpose of this study is to examine the hydrolysis kinetics of sweet sorghum stem dregs with cocktail enzymes using several models, namely the Valjamae, Kopelman, and Gompertz models. The hydrolysis was carried out at a concentration of 1/16.7 g/mL, a temperature of 50°C, and at variations of time (0, 12, 24, 36, 48, 60 and 72 minutes). The cocktail enzyme used was Multifect CL, which contains endoglucanases, exoglucanases, and β-glucosidases and has the potential to convert lignocellulose. The reactor used is CSTR (Continuous Stirred-Tank Reactor). The study results indicated that the hydrolysis kinetics of the Valjamae and Kopelman models were very suitable. The value of reaction rate constant and exponential fractal for the Valjamae model are 0.077 L/hour and 0.434 and for the Kopelman model are 0.044 L/hour and 0.415. The hydrolysis kinetics for the Gompertz model is not suitable. These hydrolysis kinetic parameters can be utilized in the bioreactors planning that will be used in the preliminary design of the biomass-based bioethanol industry.
Bioremediation of iron and manganese heavy metal polluted soil by mixed culture of Acetobacter tropicalis and Lactobacillus fermentum
Authors: Nugraha H T , Rinanti A , Wijayanti A , Aphirta S
Published: June 2023

The research aim was to determine the growth response of mixed cultures of Acetobacter tropicalis and Lactobacillus fermentum in Stone Mineral Salt solutions (SMSs) and soil containing Acid Mine Drainage (AMD) in controlled batches. The first stage was the cultivation in SMSs followed by preparation of the pollutant source and sensitivity test. The second phase was the removal of heavy metals from iron and manganese in AMD by mixed bacterial cultures in SMSs with the contact time for 48, 96, 144, 192 hours, and pH 2, 3, 5, 7. The third stage was the removal on soil media with the same contact time. Research result showed that the sensitivity test of bacterium was resistant to heavy metals iron and manganese. The highest removal efficiency of iron and manganese was 94.89% at a contact time of 96 hours, while the highest removal efficiency at pH 7 was 93.79%. The removal of iron and manganese heavy metals on soil had a removal efficiency of 69.91% at a contact time of 144 hours. This study showed that a mixed culture of Acetobacter tropicalis and Lactobacillus fermentum could be an effective bacterium in removing heavy metals from iron and manganese in AMD-contaminated soil.
An Overview Study of Flowslide Liquefaction in Petobo, Palu, Indonesia
Authors: Upomo Togani Cahyadi , Chang Muhsiung , Kusumawardani Rini , Prayitno Galih Ady , Huang Ren-Chung , Fansuri Muhammad Hamzah
Published: June 2023

A magnitude (Mw) 7.5 Palu-Donggala earthquake struck Palu, Indonesia on Friday, 28 September 2018 at 18:02:44 Central Indonesia Time (GMT+8). The earthquake resulted in tsunami and flowslide liquefaction. Balaroa, Petobo, Jono Oge and South Sibalaya were affected areas of flowslide liquefaction. Area of Petobo flowslide liquefaction had the largest impact as compared to other locations. This paper emphasizes on the observations on the ground surface when liquefaction occurred in Petobo. Interviews with the survivors and living witnesses, displacement vectors with reference to buildings, observations of soil conditions and groundwater levels as well as descriptions of conditions pre- and post-slide, are conducted in these observations. In addition, several data consisting of Satellite Imagery, DEM (Digital Elevation Model), regional geology and some photographs taken at the site are also discussed. Results show the slope of the area of flowslide liquefaction ranges from 1° to 2°. Besides earthquake shaking, soil types and groundwater tables are believed to have had contributions to the flowslide liquefaction. Loose silty medium to fine sands are found in the flowslide areas. Based on interviews, witnesses indicated the liquefaction occurred in about few seconds after the initiation of shaking. The ground then became like muddy flow and buildings started to move or sink. After flowslide, large swampy areas had appeared and the soft ground took several weeks to become hardened again.
Diesel Engine Performance using Pertamina Dex and Biodiesel (B30) on RPM and Fuel Consumption
Authors: Setiyawan A , Fitriyana D F , Bahatmaka A , Firmansyah H N , Darsono F B , Aryadi W , Kriswanto  , Roziqin A , Naryanto R F
Published: June 2023

The need for fossil fuels is increasing every year. Various threats were made to obtain efficient fuel consumption. This study aims to determine the effect of Pertamina Dex and biodiesel on RPM and fuel consumption. The method used is an experiment on a diesel engine. Mixing Pertamina Dex fuel and biodiesel with a certain composition. The mixing variations were 0%, 10%, 30%, 40%, and 50% biodiesel and variations at 1000RPM, 1500RPM, and 2000RPM. The results of this study are (1) Pertamina Dex 100% is the most efficient fuel at 1000 RPM and 1500 RPM, (2) a mixture of 70% Pertamina Dex 30% Biodiesel is the most efficient fuel at 2000 RPM, and (3) Pertamina Dex 100% is the most fuel-efficient at 1000, 2000 and 3000 RPM.
Method EWMA (Exponentially Weighted Moving Average) as a Filter to Fine and Remove Noise on Time Series Data
Authors: Andrasto Tatyantoro , Ristanto Riska Dami , Sukamta Sri , Aufa Agung , Hafidz Choirozyad Muhammad , Sandyawan Bernadus , Alfarisi Ahmad Faisal
Published: June 2023

The Moving Average method is the most common filter in Digital Signal Processing, the Moving Average method is optimal for reducing unstable value fluctuations due to interference by maintaining accurate readings. Therefore it is often used for signal coding in the context of time (Smith, 1999). The kind of moving average method is the Exponentially Weighted Moving Average (EWMA) which is often applied to a time sequence of random variables, by calculating the weighted average of the sequence by applying a weight that decreases geometrically with the length of observation (Perry, 2011). this method can be applied to tools/instruments that use data continuously in a certain time so that it will require a filter so that the fluctuations in the data are not extreme which will result in changes in the output response being softer so as not to damage the device on the output. This study uses the EWMA method to eliminate noise in the processing of sensor readings. The results of the study, the system is able to monitor realtime ph and temperature data. In fish farming, measuring and monitoring water temperature and ph is important, if it is not regularly measured and monitored it can cause various problems such as pH and temperature that are not optimal for fish growth and health. The research method to be carried out is R&D, EWMA will be applied to a multi-sensor circuit then processed by a data logger device to then be displayed on serial data on its output.
The Bearing Capacity Analysis of Deep Foundation based on In-situ Dynamic Penetration Test Compared to Pile Driving Analyzer (PDA)
Authors: Sari Undayani Cita , Mirza Abdillah Pratama M. , Atpriyanti Dinar Nurina , Negoro Narendra Aji
Published: June 2023

On road/ bridge construction, foundation stability analysis is carried out by reviewing the bearing capacity. At the planning stage, this aspect can be calculated based on empirical and numerical methods using In-situ Dynamic Penetration Test data. Meanwhile, at the implementation stage, the bearing capacity results are checked using Pile Driving Analyzer (PDA). Hereinafter, the bearing capacity result in the field is compared with the bearing capacity result at the planning stage whether they are appropriate or not. In this study, the results of bearing capacity based on empirical using Meyerhoff and Schmertmann and numerical methods using MIDAS GTS NX were compared with the results of the PDA test. This study takes an overview of the Semarang – Demak Toll Road Development Project Package 2 STA 16 + 075. The analysis was carried out based on three STA points. The results obtained show that the largest deviation value is when the PDA result is compared with the Schmertmann method, which is 0.59 and the smallest deviation is when comparing PDA with MIDAS 0.03. Both deviations are located on P 133F STA 16+711. This different deviation is due to the ultimate bearing capacity analysis based on empirical equations that only analyze single piles based on the original soil properties, while the MIDAS analysis also considers pile parameters and interface parameters. Moreover, in the PDA test, there are factors of environmental conditions.
The quality of Jatropha leaf ecoprint products using steaming and pounding techniques
Authors: Nurmasitah Sita , Sangadah Siti Fatonati , Musdalifah
Published: June 2023

A new technique in textile coloring, namely the ecoprint dyeing technique, has emerged which further proves the development of the textile industry. There are several techniques of ecoprint which are steaming technique, pounding technique and boiling technique. To produce a good eco print color, one must consider the ecoprint coloring technique, the type of textile material used, the type of mordant substance, the mass of the mordant substance, and the length of the coloring process. Mordant alum is more widely used as a fixator because it is easier to obtain and more affordable. Meanwhile, one of the natural coloring substances that can be used as natural dye is Jatropha leaves (Jatropha curcas L.). Researchers then further revealed the use of Jatropha leaves to color the textile because it has the potential to be used as natural fiber-based dyes for textiles. The independent variable used in this study is the ecoprint technique, including steaming (X1), pounding (X2), and boiling (X3). Meanwhile, the dependent variable is the quality of eco prints results with indicators including: colors difference and darkness. The data analysis method used in this research is descriptive and inferential statistics. The dyeing process on cotton cloth using alum fixation treatment and the bottom pounding method resulting the highest color darkness compared to other coloring methods. The bottom pounding method produces the darkest color. Statistical results of ANOVA test showed that there was a significant effect on the test results.
Travel Route Selection Model After the Operation of the Semarang-Demak Toll Road
Authors: Fahrenza Mohammad Fadhil , Arizky Erza Refitama , Ismiyati Ismiyati , Wicaksono Y I
Published: June 2023

The highway is an infrastructure that is very supportive for the movement of community activities. So that the government develops a road network specifically in the Java area in the form of the Semarang-Demak toll road construction. The purpose of this study is to obtain a route choice model that can explain the probability of road users choosing toll roads, and to estimate the sensitivity of route choice if there is a change in its attributes. The stated preference questionnaire was used as a medium to obtain primary data. This study uses two variables: the difference in toll rates and the difference in travel time. The survey results were processed using the binomial logit model. Regression analysis using SPSS program to obtain the utility function. The model results obtained are Utol – Unontol = -5.813 - 0.000727(X1) + 0.251(X2). The results of the utility calculation are used to obtain the probability value of choosing a travel route. If the toll rate remains or does not change, the probability of respondents to use the toll road will be greater. On the other hand, if there is an increase in toll rates, respondents tend to choose to use the national road
Multi-criteria Genetic Algorithm Optimization Approach for Balancing Bicopter Control
Authors: Apriaskar Esa , Prastiyanto Dhidik , Manaf Akhyar Abdillah , Amelia Ilya , Fahmizal
Published: June 2023

Efforts to find the best controller for stabilizing a flying vehicle have been widely developed in recent years. This work aims to join the development track by exploring the use of genetic algorithm (GA) to find the most optimum controller parameter considering settling time and overshoot criteria. Roll attitude control of a balancing bicopter was chosen as the applied plant to confirm the designed method. The controller structure applied in this research is an ideal proportional-integral (PI) controller. Two equations considering the highlighted criteria for the objective function of the GA were developed with one of them involving integral absolute error (IAE) (MCIAE-GA), and the other one does not (MC-GA). Two GAs with both equations were compared to ziegler-nichols and the one with a standalone IAE (IAE-GA). The test results confirm that the proposed MC-GA and MCIAE-GA outperform the comparative controllers at their best performance by keeping the settling time as small as possible without overshooting. Despite the latter showing a slightly faster settling time, the former has better repeatability given a smaller standard deviation for Kp and Ki parameters with a mere 0.0820 and 0.0980, respectively.
The Effect of Opak Fault on Liquefaction Potential at Toll Road Construction in Klaten Regency, Central Java
Authors: Yulianisa Y , Hardiyatmo H C , Faris F
Published: June 2023

The activity of the Opak Fault on May 27th, 2006, caused a strong earthquake of Mw 6.3, then known as the Yogyakarta Earthquake. Previous studies have shown that several damages during the earthquake were caused by liquefaction. This paper aims to determine potential liquefaction hazards at toll road construction in Klaten Regency, within less than 10 km of the Opak Fault. The liquefaction potential was analyzed from Standard Penetration data using the simplified procedure to determine the safety factor and Liquefaction Potential Index by Iwasaki et al. (1981). In addition, vertical displacement caused by liquefied soil was calculated using the equation developed by Yoshimine et al. (2006). Based on the analysis of the liquefaction potential of 10 boreholes, the results showed that liquefaction occurs at 6 boreholes, with a high to a very high level of liquefaction potential index with a maximum horizontal acceleration of at least 0.46g. The extensive ground surface damage potentially occurs at 2 boreholes, with the vertical settlement of 32.55 cm and 47.02 cm, which occur at the nearest site distance to Opak Fault.
Effect of Contact Time on The Adsorption Process of Activated Carbon from Banana Peel in Reducing Heavy Metal Cd and Dyes Using a Stirring Tub (Pilot Scale)
Authors: Wahyuhadi M E , Kusumadewi R A , Hadisoebroto R
Published: June 2023

One of the most successful processes for extracting, recovering, and recycling metals from wastewater is adsorption utilizing natural activated carbon, such as banana peel waste. This is advantageous for a wastewater treatment sector since natural activated carbon is less expensive than conventional activated carbon. The aim of this research is to determine the optimum contact time at removing heavy metals and colour using a stirrer tub (pilot scale). Physically, banana peels would be burned at a high temperature of 300°C, and chemically, they would be activated with a 20% sulfuric acid (H2SO4) solution. A mixing tank with a volume of 30 L and a stirring machine spinning at 200 rpm was employed as a contact point between wastewater and activated carbon. Time variations of 15, 30, 60, 75, and 90 minutes were explored to find the best contact time. The ideal circumstances for 75 minutes obtained a Cd metal removal effectiveness of 98.63% with an adsorption capacity of 0.38 mg/g, according to the findings. At the optimum time of 90 minutes, the kepok banana peel was 97.38% successful in absorbing the color using a stirrer.
Study optimization cement content of cement treated base (CTB) using compressive strength parameter
Authors: Priastiwi Y A , Sukamta  , Hidayat A , Hafidz M , Widyandika R , Wiguna E
Published: June 2023

Cement Treated Base (CTB) is a foundation layer (base course) on flexible pavement and the development of a soil-cement foundation commonly used in construction that receives high loads. Generally, CTB is a combination of coarse aggregate (split), fine aggregate, cement, and water with zero slumps. The purpose of this study was to determine the optimum cement content of the CTB mixture with variations in the cement content of 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, and 5.5% of the dry weight of the aggregate and the effect of cement content on the compressive strength of the resulting CTB. Experimental research in the laboratory with 15/30 cm cylindrical specimens was carried out and analyzed. The results showed that the optimum CTB for the material used in this study was 3.75% which was obtained through the graph of the relationship between compressive strength and cement content, and from all variations of cement content made the cement content of 4% with a compressive strength of 54.21 kg/cm2 that meets the general specifications of 2018 Highways, namely 45 – 55 kg/cm2.
Utilization of corncob waste as bioethanol raw material by activities of Dekkera Bruxellensis and Saccharomyces Cerevisiae
Authors: Arby A Q A , Rinanti A , Wijayanti A , Marendra S M P
Published: June 2023

Corncob waste is not managed properly has the potential to environmental pollution. The purpose of this reasearch is to utilize corncob waste as a potential biomass into bioethanol. Process of making bioethanol is carried out in 4 steps, namely delignification, hydrolysis, fermentation, distillation. Corncob as substrate were prepared mechanically to become size powder 40 mesh. Delignification by fungi Dekkera Bruxellensis was varied with substrate ratio of 5, 10, and 15 grams at contact times of 3, 5, and 7 days. Hydrolysis with 2% sulfuric acid (H2SO4) at contact times of 30, 45, and 60 minutes. Glucose concentration was measured uing 3, 5-dinitrosalicylate (DBS) method. Variations of fungi:ragi = 1:1 at contact times of 3, 5, and 7 days. Distillation at temperature of 78°C using Gas Chromatography–Mass Spectrophotometry (GC-MS). This result in optimum delignification at substrate variation of 5 grams at contact time of 7 days, with a lignin removal 20,72%. The optimum glucose concentration in hydrolysis produced 7,561 g/L glucose at 2% Sulfuric acid (H2SO4). The highest ethanol content of 2,95% occured in ratio fungi:yeast 1:1 with substrate of 5 grams during 7 days. Based on pilot scale calculation with diameter 1,9 m and height of 0,9 m, then for 100 kg of corncobs can be produce 4,133L total ethanol.
Bio Oil Production from Multi-Feed Stock Biomass Waste and The Upgrading Process for Quality Improvement - Mini Review
Authors: Prasetiawan H , Hadiyanto  , Fardhyanti D S , Fatriasari W , Chafidz A , Rakasiwi A G , Kaja Y V , Rahma N F , Laili I R
Published: June 2023

Bio-oil is an environmentally friendly liquid fuel produced from the condensation of vapor product of pyrolysis process. Bio-oil has higher calorific value compared to other oxygenated fuels (such as methanol), but its calorific value is still lower than diesel and other light fuel oils. Bio-oil can be used directly as fuel; however, it has several characteristics that adversely affect high-tech machines. Bio-oil is corrosive since it has a high acidity level, unstable at room temperature due to the high content of oxygenate compounds and has a low higher heating value (HHV) due to its high water content. Therefore, an upgrading process is needed to improve the quality before it can be further processed into liquid fuel and chemicals. Meanwhile, the raw material for bio-oil also varies, not only using single feedstock but also using mixed feedstock. However, studies on mixed bio-oil raw materials are still very limited. Thus, it is possible to study the process of producing bio-oil from a mixture of biomass waste using the catalytic pyrolysis method and improve the quality of bio-oil through the collection of phenolic compounds using the extraction process.
Simulation of Esterification-Transesterification of Waste Cooking Oil to Produce Biodiesel using Ultrasound Assisted Integrated Double Column Reactive Distillation
Authors: Kusumaningtyas R D , Budiono Y W P , Kusuma A D H , Prasetiawan H , Ardiansyah H , Hidayat M
Published: June 2023

There are some problems arising related to the utilization of fossil-based fuel due to the diminishing of oil reserves. Therefore, energy transition toward the development of new and renewable energy has been set in Indonesia. Biodiesel is a promising renewable energy resource which can be synthesized from vegetable oils as feedstock via transesterification reaction. Waste cooking oil (WCO) is among the economical and abundant raw materials for biodiesel production. It contains triglyceride and free fatty acid (FFA) of 78.16% and 21.84%, respectively. Biodiesel preparation is generally carried out using conventional batch or continuous mixed flow reactors. This configuration encounters challenge related to the high cost for setting up the separation process. To overwhelm this drawback, it is essential to develop reactor which integrates the reaction and separation process. In this work, a novel design of Ultrasound Assisted Integrated Double Column Reactive Distillation (UAIDCRD) was introduced and simulated for biodiesel preparation through a coupling esterification-transesterification reaction. The first column was applied the esterification of Simulation of UAIDCRD for biodiesel production was conducted using ASPEN Plus v10. Model thermodynamic selected for the simulation was UNIQUAC. Sensitivity analysis was performed to examine the effects of reflux ratio, bottom to feed ratio, and methanol to oil ratio on the reaction conversion. Reflux ratio was studied at the range of 0.5 - 200, bottom to feed ratio was evaluated at the range of 0.25 - 0.9, and methanol to oil ratio were 1:3 - 9:8. It was observed that 99.99% reaction conversion in the esterification column was achieved with the reflux ration, bottom to feed ratio, and methanol to oil ratio of 0.5, 0.5, and 4.1, respectively. On the other hand, 99.99% reaction conversion in the transesterification column was obtained with the reflux ration, bottom to feed ratio, and methanol to oil ratio of 0.5, 0.5, and 3:1. The alcohol needed for the esterification and transesterification reaction were much lower than those required for the reaction using conventional reactor.
Environmental Impact Assessment of Steel Production in Indonesia : A Case Study
Authors: Alyarahma Syifa , Sari Indah Permata , Kurniawan Wawan
Published: June 2023

One of the biggest energy consumers and CO2 emitters in the world is the steel sector. With the growth in infrastructure construction, steel output has risen year over year. Therefore, a life cycle assessment of inputs and outputs at each stage of the steel manufacturing process is necessary to enable the adoption of life cycle management and offer sustainable production and consumption. The Life Cycle Assessment method is employed in this study to assess the environmental effects of steel manufacturing in Indonesia. The CML-IA baseline method, which assesses several impact categories including global warming, ozone layer depletion, acidification, and eutrophication, and others impact was used in this study and SimaPro 9.2 software was used to calculate the environmental impact of steel production. According to the findings, the largest contributors to the overall impact are the electric arc furnace, rolling mills, ladle furnaces, which use chemicals, and reheating furnaces, which use LPG. The entire impact of the steel manufacturing process on global warming, using a functional unit of 1 ton steel, is 1215.17 kg CO2 eq, of which the Electric Arc Furnace (EAF) contributes 477.37 kg CO2 eq, or 39% of the total CO2 emissions. Based on these findings, an effort is therefore required to reduce the consumption of fuel in the reheating furnace as well as electricity in the EAF and rolling mills.
Determination of the optimum organic coagulants dosage in tofu industrial wastewater treatment
Authors: Aphirta S , Ratnaningsih R , Hadisoebroto R , Yusuf A M , Gantara H
Published: June 2023

The research aim was to analyze the optimum dosage of moringa seed and tamarind seed as an organic coagulant in removing tofu wastewater pollutants using coagulation, flocculation, and sedimentation reactors. The first step is the manufacture of coagulant by processing the organic coagulant raw materials into powder and filtered using a 50 mesh filter and dried. The second step is to determine the dosage of coagulant using 4 variations of pH 5,6,7,8 using NaOH solution, and coagulant dosages obtained 2,3,4,5 gr/L. The third stage is an experimental test using the squenching batch reactor (SBR) method with TSS and COD parameter analysis. The effects confirmed that the coagulant of moringa seed had better ability than tamarind seed in removing TSS and COD, with the highest percentage reduction in TSS and COD at 3 gr dose of moringa seed. In addition, removal of TSS and COD using moringa seed or tamarind seed as coagulant was the most optimum at neutral pH 7-8. However, the treatment of tofu wastewater using either moringa seed or tamarind seed as coagulant using the coagulation-flocculation-sedimentation method in one reactor is not able to remove pollutants to meet the quality standards, so further treatment is needed.
A commentary update on NICE CG124. Hip fracture:management (2023)
Authors: Ong Terence , Vindlacheruvu Madhavi
Published: June 2023

The National Institute for Health and Care Excellence released its second update on hip fracture management in early 2023. First published in 2011, the last update was in 2017. The scope of this recent update focussed on surgical implants for hip fracture. This included recommendation to offer total hip replacements instead of hemiarthroplasty for displaced intracapsular hip fractures, and a move away from Orthopaedic Device Evaluation Panel rated implants to a more standardised consistent choice. Other recommendations such as the importance of multidisciplinary orthogeriatric care, early surgery and prompt mobilisation remain. As the literature surrounding hip fracture management continue to grow, guidance such as this needs to continue updating itself to ensure patients with hip fracture receive the best possible care.
Reducing hip and non-vertebral fractures in institutionalised older adults by restoring inadequate intakes of protein and calcium is cost-saving
Authors: Baek Yeji , Iuliano Sandra , Robbins Judy , Poon Shirley , Seeman Ego , Ademi Zanfina
Published: June 2023

Background

older adults in aged care account for 30% of the population burden of hip fractures. Nutritional interventions to correct under nutrition reduce these debilitating fractures, perhaps partly by reducing falls and slowing deterioration in bone morphology.

Objective

to determine whether a nutritional approach to fracture risk reduction in aged care homes is cost-effective.

Design

cost-effectiveness was estimated based on results from a prospective 2-year cluster-randomised controlled trial and secondary data. Intervention residents consumed a total of 3.5 daily servings of milk, yoghurt and/or cheese, resulting in 1,142 mg of calcium and 69 g of protein compared with the daily intakes of 700 mg of calcium and 58 g of protein consumed by the control group.

Setting

fifty-six aged care homes.

Participants

residents for 27 intervention (n = 3,313) and 29 control (n = 3,911) homes.

Methods

ambulance, hospital, rehabilitation and residential care costs incurred by fracture were estimated. The incremental cost-effectiveness ratios per fracture averted within a 2-year time horizon were estimated from the Australian healthcare perspective applying a 5% discount rate on costs after the first year.

Results

intervention providing high-protein and high-calcium foods reduced fractures at a daily cost of AU$0.66 per resident. The base-case results showed that the intervention was cost-saving per fracture averted, with robust results in a variety of sensitivity and scenario analyses. Scaling the benefits of intervention equates to a saving of AU$66,780,000 annually in Australia and remained cost-saving up to a daily food expenditure of AU$1.07 per resident.

Conclusions

averting hip and other non-vertebral fractures in aged care residents by restoring nutritional inadequacy of protein and calcium is cost-saving.
Still WALKing-FOR: 2-year sustainability of the ‘WALK FOR’ intervention
Authors: Gil Efrat , Zisberg Anna , Shadmi Efrat , Gur-Yaish Nurit , Shulyaev Ksenya , Chayat Yehudith , Agmon Maayan
Published: June 2023

Background

low mobility of hospitalised older adults is associated with adverse outcomes and imposes a significant burden on healthcare and welfare systems. Various interventions have been developed to reduce this problem; at present, however, their methodologies and outcomes vary and information is lacking about their long-term sustainability. This study aimed to evaluate the 2-year sustainability of the WALK-FOR (walking for better outcomes and recovery) intervention implemented by teams in acute care medical units.

Methods

a quasi-experimental three-group comparative design (N = 366): pre-implementation, i.e. control group (n = 150), immediate post-implementation (n = 144) and 2-year post-implementation (n = 72).

Results

mean participant age was 77.6 years (± 6 standard deviation [SD]) and 45.3% were females. We conducted an analysis of variance test to evaluate the differences in primary outcomes: number of daily steps and self-reported mobility. Levels of mobility improved significantly from the pre-implementation (control) group to the immediate and 2-year post-implementation groups. Daily step count: pre-implementation (median: 1,081, mean: 1,530 SD = 1,506), immediate post-implementation (median: 2,225, mean: 2,724. SD = 1,827) and 2-year post-implementation (median: 1,439, mean: 2,582, SD = 2,390) F = 15.778 P < 0.01. Self-reported mobility: pre-implementation (mean:10.9, SD = 3.5), immediate post-implementation (mean: 12.4, SD = 2.2), 2-year post-implementation (mean: 12.7, SD = 2.2), F = 16.250, P < 0.01.

Conclusions

the WALK-FOR intervention demonstrates 2-year sustainability. The theory-driven adaptation and reliance on local personnel produce an effective infrastructure for long-lasting intervention. Future studies should evaluate sustainability from a wider perspective to inform further in-hospital intervention development and implementation.
Association of Lung Function With Cognitive Decline and Incident Dementia in the Atherosclerosis Risk in Communities Study
Authors: Shrestha Srishti , Zhu Xiaoqian , London Stephanie J , Sullivan Kevin J , Lutsey Pamela L , Windham B Gwen , Griswold Michael E , Mosley Jr Thomas H
Published: June 2023

We examined the associations between lung function and incident dementia and cognitive decline in 12,688 participants in the ARIC Study who provided lung function measurements in 1990–1992. Cognitive tests were administered up to 7 times, and dementia was ascertained through 2019. We used shared parameter models to jointly fit proportional hazard models and linear mixed-effect models to estimate lung-function–associated dementia rate and cognitive change, respectively. Higher forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were associated with reduced dementia (n = 2,452 persons developed dementia); hazard ratios per 1-L increase in FEV1 and FVC were 0.79 (95% confidence interval (CI): 0.71, 0.89) and 0.81 (95% CI: 0.74, 0.89), respectively. Each 1-L increase in FEV1 and FVC was associated with a 0.08–standard deviation (SD) (95% CI: 0.05, 0.12) and a 0.05-SD (95% CI: 0.02, 0.07) attenuation of 30-year cognitive decline, respectively. A 1% increase in FEV1/FVC ratio was associated with 0.008-SD (95% CI: 0.004, 0.012) less cognitive decline. We observed statistical interaction between FEV1 and FVC, suggesting that cognitive declines depended on values of specific FEV1 and FVC (as compared with FEV1, FVC, or FEV1/FVC ratio models that suggested linear incremental associations). Our findings may have important implications for reducing the burden of cognitive decline that is attributable to environmental exposures and associated lung function impairment.
Effects of spaced k-mers on alignment-free genotyping
Authors: Häntze Hartmut , Horton Paul
Published: June 2023

Motivation

Alignment-free, k-mer based genotyping methods are a fast alternative to alignment-based methods and are particularly well suited for genotyping larger cohorts. The sensitivity of algorithms, that work with k-mers, can be increased by using spaced seeds, however, the application of spaced seeds in k-mer based genotyping methods has not been researched yet.

Results

We add a spaced seeds functionality to the genotyping software PanGenie and use it to calculate genotypes. This significantly improves sensitivity and F-score when genotyping SNPs, indels, and structural variants on reads with low (5×) and high (30×) coverage. Improvements are greater than what could be achieved by just increasing the length of contiguous k-mers. Effect sizes are particularly large for low coverage data. If applications implement effective algorithms for hashing of spaced k-mers, spaced k-mers have the potential to become an useful technique in k-mer based genotyping.

Availability and implementation

The source code of our proposed tool MaskedPanGenie is openly available on https://github.com/hhaentze/MaskedPangenie.
A gated graph transformer for protein complex structure quality assessment and its performance in CASP15
Authors: Chen Xiao , Morehead Alex , Liu Jian , Cheng Jianlin
Published: June 2023

Motivation

Proteins interact to form complexes to carry out essential biological functions. Computational methods such as AlphaFold-multimer have been developed to predict the quaternary structures of protein complexes. An important yet largely unsolved challenge in protein complex structure prediction is to accurately estimate the quality of predicted protein complex structures without any knowledge of the corresponding native structures. Such estimations can then be used to select high-quality predicted complex structures to facilitate biomedical research such as protein function analysis and drug discovery.

Results

In this work, we introduce a new gated neighborhood-modulating graph transformer to predict the quality of 3D protein complex structures. It incorporates node and edge gates within a graph transformer framework to control information flow during graph message passing. We trained, evaluated and tested the method (called DProQA) on newly-curated protein complex datasets before the 15th Critical Assessment of Techniques for Protein Structure Prediction (CASP15) and then blindly tested it in the 2022 CASP15 experiment. The method was ranked 3rd among the single-model quality assessment methods in CASP15 in terms of the ranking loss of TM-score on 36 complex targets. The rigorous internal and external experiments demonstrate that DProQA is effective in ranking protein complex structures.

Availability and implementation

The source code, data, and pre-trained models are available at https://github.com/jianlin-cheng/DProQA.