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The dyes of the textile dyeing industry wastewater are harmful to humans and the environment. They should be treated before discharging into the environment. The adsorption using the spherical activated carbon can be effective to reduce the dyes. The spherical activated carbon of 3-7 µm in diameter was successfully prepared from the waste bagasse liquid using the hydrothermal method. The activation of this carbon was carried out using the KOH solution. The optimum pH and contact time were achieved in 2 and 200 min, respectively. Adsorption kinetic for RhB on activated spherical carbon follows the second-order kinetics and its adsorption mechanism follows the Langmuir isotherm. The maximum adsorption capacity of spherical activated carbon to Rhodamine B was achieved in 64.52 mg/g.

Sediments are particles derived from the dismantling of rocks from the land and pieces of shell and remains of marine organisms that contain organic matter, included carbonate sediment. The total carbonate sediment content was influenced by many factors, such as sediment grain type. This study aimed to determine the carbonate content in sediments and to determine their relationship to the sediment grain characteristic on the Cilacap coast. The sediment's carbonate content used the titration method, while the sediment grain test used a dry filter. Statistical analysis was used to determine the sediment grain characteristic (mean, sorting, skewness, and kurtosis). The results showed that sediments' total carbonate content had a range of 1.93% - 6.23%, with an average of 4.21%. Sediments are dominated by fine sand with very well sorted, very platykurtic, and very fine skewed characteristics. The relationship between sediment grain characteristics and total sediment carbonate content showed a good correlation due to the sorting factor. Other parameters such as mean size and skewness have been shown a low correlation, whereas kurtosis has a shallow relationship with carbonate content.

Layered double hydroxide (LDH) Ni/Al-NO3 was synthesized using a coprecipitation method under base condition following with intercalation using Keggin ion [a-SiW12O40]4- to form Ni/Al-[a-SiW12O40] LDH. The LDHs were characterized using XRD, FTIR, BET, and pHpzc analyses. Furthermore, LDHs were applied as adsorbent of iron(II) from aqueous solution. The adsorption process was studied through the effect of adsorption time, the concentration of iron(II), and temperature adsorption. The results show the interlayer distance of LDHs was increased from 7.408 Å to 10.533 Å after intercalation process. The adsorption of iron(II) on LDHs showed that adsorption of iron(II) on both LDHs follows pseudo first-order kinetic model with R2 value is close to one. The adsorption process was spontaneous, with adsorption capacity up to 36.496 mg g-1.

The defect and metallic silver (Ag) in silver phosphate (Ag3PO4) photocatalyst were successfully generated using hydroxyapatite (HA) and glucose. Two steps of synthesis were done in these experiments. Firstly, the Ag/HA powder was prepared by reacting AgNO3 and HA, followed by the addition of a glucose solution. Secondly, the suspension of Ag/HA was reacted with AgNO3 aqueous solution. The yellow product of Ag/Ag3PO4 photocatalyst was produced. The products were characterized using X-Ray Diffraction (XRD), Diffuse Reflectance Spectroscopy (DRS), Scanning Electron Microscope (SEM), Brunauer–Emmett–Teller (BET) and X-ray Photoelectron Spectroscopy (XPS). The decreased ratio of O/Ag and metallic Ag formation observed by the XPS was detected as the possible defect and Ag-doping in the photocatalyst. The enhanced photocatalytic activity might be caused by the oxygen vacancy and metallic Ag in Ag3PO4 that enables the separation of photo-generated electrons and holes.

Tuning the morphology of Ag3PO4 photocatalysts with an elevated concentration of KH2PO4 have been successfully conducted. This photocatalyst was prepared by starting material of AgNO3 and KH2PO4. The KH2PO4 aqueous solution with five concentrations of 0.10 M, 0.15 M, 0.30 M, 0.45 M, and 0.60 M was reacted with AgNO3 aqueous solution. The products were characterized using X-ray Diffraction (XRD), UV-Vis Diffuse Reflectance Spectroscopy (DRS), and Scanning Electron Microscopy (SEM). The concentration of KH2PO4 significantly affected the morphology, size, and crystallinity of catalyst. The morphology of Ag3PO4 may be tuned with the synthesis using an elevated concentration of KH2PO4. The sample with the synthesis using 0.15 M of KH2PO4 exhibited the excellent photocatalytic activity. The high photocatalytic activity was caused by the small size of mixed morphology of sphere and tetrahedron, high crystallinity and defect sites.

Ca/Al layered double hydroxides (Ca/Al LDH) was synthesized using co-precipitation method following calcination at 800 °C and was intercalated with Keggin ion [α-SiW12O40]4– to form intercalated Ca/Al LDH. Materials were characterized using XRD and FTIR spectrophotometer. Furthermore, materials were used as an adsorbent of cadmium(II) from solution. The results showed that layer material was formed completely after calcination which was indicated at diffraction 20° due to loss of water in the interlayer space. Ca/Al LDH after calcination was intercalated with [α-SiW12O40]4– ion and interlayer distance was increased from 4.25 to 4.41 Å showed that intercalation process was successfully conducted. Adsorption of cadmium(II) using Ca/Al LDH was conducted at pH 9 and intercalated Ca/Al LDH at pH 8 showed that intercalated material has slightly faster than Ca/Al LDH without intercalation probably due to slightly increasing interlayer distance of Ca/Al LDH after intercalation. The adsorption capacity of intercalated Ca/Al LDH was higher than Ca/Al LDH without intercalation at the temperature range of 30–50 °C.

Geochemical fractionation of Cadmium (Cd), Lead (Pb), Cobalt (Co), Zink (Zn), Iron (Fe) and Manganese (Mn) in sediment of the East China Sea were determined using four-stages of modified BCR sequential extraction method combination with ICP-MS. The total concentration of trace metals in sediment samples were in the following order: Fe >Mn>Pb> Zn > Co > Cd. Cd is present mainly in acid soluble fraction. Pb and Mn are in the group with presenting of easy reducible fraction and acid soluble fraction. Fe and Co were found in a group with mainly in residual fraction, while Zn was distributed in all four fractions. The highest contamination factors were found for Cd and Mn while the lowest were found for Fe and Co in almost station. The result showed low risk for Fe and Co in all station, Pb (except S2 and S3), Zn at S3,S6 and S7, and Mn at S1. A medium risk is indicated for Pb at S2 and S3, Zn at S1 and S5, and Mn at S2 and S6. A high risk showed for Zn at S2 and S4, and Mn at S4 and S5, while Cd at almost station (except S4) was very high risk.

Waste containing hazardous and toxic chemical compounds into the environment leads to water pollution, soil and air. These chemical compounds will endanger human life and environment. One type of compound that may pollute the environment is chromium. The metal is commonly found in industrial waste such as from exhaust and industrial wastewater from etal plating company. The purpose of this research is to utilize coconut shell charcoal and soil humus as a low-cost and ready-made alternative material to reduce the concentration chromium (Cr) on wastewater. Humus was taken from Baturraden region and was isolated using NaOH extraction and was furthermore purified using mixtures of HF(aq): HCl(aq). Coconut shell charcoal was produced and was mixed with the humus. Adsorption process was carried out by batch method on variations of charcoal: humus composition, pH, and contact time. Humus soil was identified using infrared spectrophotometry (IR). Determination of chromium concentration was performed using atomic absorption spectroscopy (AAS). The purified humus yielded was 25.92% (w/w), with 34.18% moisture, and ash content of 18.09%. The results showed that the variation of composition ratio of 2:1 charcoal and humus produced the greatest percent reduction of 18.20%, and the optimum pH for the adsorption is 9. For the variation of contacts time, the optimum reaction time is at 180minutes with decreasing concentration of Pb up to 56.07%.

This research is conducted to produce carbons from coconut fibre which approach to activated carbon clause continue with carbon surface modification and the adsorption examination to Cu(II) ions. The research consist of several phase. Carbon making of coconut fibre conducted by carbonization processes at 320-400oC with temperature interval 20oC. Carbon yielded in characterized moisture content, ash content and its adsoprtion to iodium. The carbon surface modification conducted by loaded 2-mercaptobenzotiazol (MBT) on carbon. The adsorpsibility of carbon-MBT tested by influence of contact time, pH, and the isoterm adsorption pattern. The result of the study showed carbonization of coconut fibre which approach the requirement of SII No.0258-89 gained at temperature 320oC. In the present study equilibrium time of 10 minute and pH was found to be optimum for both adsorbent. While type of isothermal adsorption from carban and carbon-MBT adsorbent followed the Langmuir adsorption pattern.

The hardness water is not good for consumption because can resulted kidney disease One of the method which can be used to degrade rodamin B is adsorption use humin. Humin is biggest fraction of humat materials that insoluble in acid, alcohol and base. The ability of humin for adsorp Ca2+ and Mg2+ caused by the existence of OH phenolic and carboxylic functional group which can interacted with metal ion. The aim of this study is to recognize humin characteristic from the soil of Baturraden resin forest, and ability of humin from the soil of Baturraden resin forest for decreasing the hardness water. Humin was isolated from the Baturraden resin forest and purified use mixture of HCl:HF. Purified humin is characterised such as identify of functional group of humin, stipulating of water content, stipulating of dust content, obstetrical stipulating of total acidity content, carboxylic and OH phenolic functional group. Decreasing of hardness water was analysed with variation time 0, 10, 30, 60, 180, 300, 600, 900, 1200 dan 1440 minute. Humin that isolated from Baturraden resin forest have characteristic such as water content 16.6199 %; dust content 9.2050 %; total acidity content 475 cmol / Kg; carboxylic rate 200 cmol/Kg, and OH phenolic rate 275 cmol/Kg. Decreasing of hardness water in Darmakradenan, Ajibarang subdistrict, Banyumas regency was 54,745 % with equlibrium time at 600 minute (10 hours).

Congo red is one of dyes-stuff in textile industry wastwater. If it is thrown directly without waste management process, the dyes could pollute environtment, especially soil. Humin has OH phenolic and carboxylic functional group which can interacted with congo red. The aim of this study is recognize humin characteristic from the soil of Baturraden resin forest, determine the adsorption capacity and isotherm adsorption pattern of congo red by humin from the soil of Baturraden resin forest. Humin in this study is isolated from the soil of Baturraden resin forest. soil cleared of gravel and dirt, then it extracted by using NaOH of nitrogen atmosphere and purified to applies mixture HCl:HF. Humin that is obtained is used to be interacted with dyes with various contact time, various of pH and concentration of congo red so that the adsorption capacities and isotherm adsorption pattern can be obtained. Result of the study showed that the humin has water content 34.92 %, dust content 8.64 %, total acidity 475 cmol/Kg, carboxylic rate 272.5 cmol/Kg, and OH Phenolic rate 202.5 cmol/Kg. The optimum contact time of congo red adsorption by humin is 40 minutes, with optimum pH is 7, adsorption capacities 57.14 mg/g and isotherm adsorption pattern of congo red by humin is follow the pattern of Langmuir isotherm adsorption.

Study about the use of active charcoal rice straws (AAJP) was done in order to decrease heavy metal ion on textile waste water by using photocatalyst AAJP/TiO2. Rice straws were gained from the Banyumas Regency and samples textile waste water from one of textile industry in Pemalang. This study was begun by the making of active charcoal from the rice straws, and then the modification of photocatalyst AAJP/TiO2 was done with the comparison 1:99, 2:98, 3:97, 4:96, 5:95. The test of heavy metal ion photoreduction was done with some parameters such as weight comparison (1:99, 2:98, 3:97, 4:96, 5:95), pH effect (2, 5, 7, 9, 13) and the effect of ray source (sun light and the UV lamp). Analysis of photocatalyst material used SEM and heavy metal ion concentration used AAS. Results show that optimum photocatalyst activity in weight comparison AAJP300oC / TiO2 (1:99) with decrease concentration was 65.02% for heavy metal ion, mean while AAJP700oC / TiO2 (3:97) with decreased concentration of heavy metal ion is 94.50%. Optimal process for heavy metal ion reduction occur at pH 2 with decreased concentration of heavy metal ion for AAJP300oC / TiO2 (1:99) is 99.87% and for AAJP700oC /TiO2 (3:97) is 100%. The source of UV lamp was good for heavy metal ion photoreduction (AAJP300oC/TiO2(1:99) was 99.87% and AAJP700oC/TiO2 (3:97) was 100%)

Humin was isolated from the Baturraden resin forest and purified use mixture of HCl:HF. Purified humin is characterised such as identify of functional group of humin, stipulating of water content, stipulating of dust content, obstetrical stipulating of total acidity content, carboxylic and OH phenolic functional group. The adsorption of rodamin by humin measured by UV-Visible spectrophotometer at maximum wavelength of rodamin B liquid, optimum pH and optimum contact time to determine absorbtion capacities and isotherm adsorption pattern .Humin that isolated from Baturraden resin forest have characteristic such as water content 16.6199 %; dust content 9.2050 %; total acidity content 475 cmol / Kg; carboxylic rate 200 cmol/Kg, and OH phenolic rate 275 cmol/Kg. Maximum wavelength of rodamin B is 554 nm and optimum contact time of adsorption rodamin B by humin is 180 minute with optimum pH 4. Adsorption rodamin B by humin follows the pattern of Langmuir isotherm adsorption with the value of R2 is 0.9801 and absorption capacities is 39,5257 mg/g.

Although humic substances consist mosly of humin (65%), however its characteristic in Cu(II) odsorption is not yet clearly revealed. In this work, humin was isolated from peat soil of west Kalimantan, purified and then interacted with Cu(II). The purity of isolated humin was determined by its ash content. The funtional group in this purified humin was characterized qualitatively by FTIR and quantitatively by titration. Study on the solubility of Cu(II) in freshwater was carried out at pH from 2-12 in the presence and without purified humin. To obtain adsorption kinetic parameters of Cu(II) on humin in freshwater, study based on Langmuir-Hinshelwood was carried out, while for its thermodinamics parameters, a study based on Langmuir and Freundlich were employed. The ash content of purified humin was 1,58 % (w/w), it showed that the humin was in pure condition. The active fungtional group identified humin were –COOH (1700 cm-1) 115 cmol/kg and –OH fenolic (3421,5 cm-1) 562 cmol/kg. At 27 all of Cu(II) was precipitated as Cu(OH)2. The rate constant for Cu(II) in freshwater medium were 2,7 x 10-3 S-1 and 0,6 x 10-3 S-1. The obtained curve fitting of langmuir and freundlich adsorption showed that Langmuir model fit better than Freundlich, indicated that the adsorption reaction are of monolayer. The adsorption capacities of Cu(II) on humin in freshwater was 3,033 x 10-4 mol/g

This article aims to identify the status of construction industry practitioners in Indonesia in terms of their knowledge and current practices as well as the barriers for implementing Building Information Modelling (BIM). This study utilises a questionnaire survey, aimed at the construction industry practitioners in Indonesia. The result shows that BIM is still a novelty for the construction practitioners in Indonesia. This is backed with the finding that more than 60% of the respondents was not familiar with BIM terminology or did not have proper knowledge of BIM terminology. More than 70% of the respondents' projects have implemented BIM Level 1, mostly in transportation service, energy production and distribution, roads and bridges, and the building infrastructure category. The five highest ranks of barriers to BIM implementation are lack of BIM training, lack of BIM experience and capability, no client demand, high cost in software and hardware acquisition, and inadequate information technology (IT) facilities. The recommended strategy should be initiated by the government, by conducting a comprehensive familiarisation programme covering BIM knowledge, BIM advantages and BIM implementation in the industry. At the same time, the government should prepare regulations and standards as guidance to BIM implementation in Indonesia. [ABSTRACT FROM AUTHOR]

Change orders in construction projects are very common and result in negative impacts on various project facets. The impact of change orders on labor productivity is particularly difficult to quantify. Traditional approaches are inadequate to calculate the complex input-output relationship necessary to measure the effect of change orders. This study develops the Evolutionary Fuzzy Support Vector Machines Inference Model (EFSIM) to more accurately predict change-order-related productivity losses. The EFSIM is an AI-based tool that combines fuzzy logic (FL), support vector machine (SVM), and fast messy genetic algorithm (fmGA). The SVM is utilized as a supervised learning technique to solve classification and regression problems; the FL is used to quantify vagueness and uncertainty; and the fmGA is applied to optimize model parameters. A case study is presented to demonstrate and validate EFSIM performance. Simulation results and our validation against previous studies demonstrate that the EFSIM predicts the impact of change orders significantly better than other AI-based tools including the artificial neural network (ANN), support vector machine (SVM), and evolutionary support vector machine inference model (ESIM). [ABSTRACT FROM PUBLISHER]

This study conducts a mechanism enhancing the time series data treatment of the time-dependent evolutionary fuzzy support vector machine inference model (EFSIMT). The enhanced model, EFSIMET, was developed particularly to treat construction management problems that contain time series data. EFSIMET is an artificial intelligent hybrid system in which fuzzy logic (FL) deal with vagueness and approximate reasoning; support vector machine (SVM) acts as supervise learning tool; and fast messy genetic algorithm (fmGA) works to optimize FL and SVMs parameters simultaneously. Moreover, to capture the time series data characteristics, the inference model develops fmGA-based searching mechanism to seek suitable weight values to weight the training data points. This random-based searching mechanism has capacity to address the complex and dynamic nature of time series data; thus, it could improve the model's performance significantly. Nowadays, construction managementis facing complex and difficult problems due to the increasing uncertainties during project implementation. Therefore, the second objective of this study is proposed for the application of EFSIMET to treat two typical problems in construction: forecasting cash flow and estimate at completion. Through performance's comparison with previous works, the effectiveness and reliability of EFSIMET are proven. Hence, this model may be used as an intelligent decision support tool to assist the decision-making process to solve the construction management's difficulties. [ABSTRACT FROM AUTHOR]

There are many factors that affect the success of the implementation process of a project. The importance of each of these factors varies according to the different phases of the project lifecycle, which makes it very difficult to predict the final result of a project. In practice, foreseeing the result of a project is based on the judgment of those in management, which is grounded in their experience. This study aimed to build an Evolutionary Gaussian Process Inference Model (EGPIM), using a Gaussian process, along with Bayesian inference and particle swarm optimization, which helps to optimize the hyper-parameters required for making Gaussian process predictions. With this model at its core, this study can efficiently extract expert knowledge and experience from case studies and historical data to determine relationships between factors which significantly influence the outcome of a project so that its success may be predicted. Historical cases were ordered as a time series based on the Continuous Assessment of Project Performance (CAPP) research results. The model was trained using the EGPIM and these cases to predict the success of a project. This model proved quite accurate at predicting the success of a project and had outstanding performance in time-series applications. [ABSTRACT FROM AUTHOR]