bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation of kerr nonlinearity: revealing initial state dependency
Authors: Agasti Souvik
Published: September 2023

We simulate coherent driven free dissipative Kerr nonlinear system numerically using time-evolving block decimation (TEBD) algorithm and time propagation on the Heisenberg equation of motion using Euler’s method to study how the numerical results are analogous to classical bistability . The system evolves through different trajectories to stabilize different branches for different external drives and initial conditions. The Wigner state reprentation confirms the system to suffer a residual effect of initial state throughout the non-classical dynamical evolution and the metastable states of the system . Furthermore, we also see the numerically simulated spectral density remains significantly different from analytical counterparts when initial states do not lie to the same branch of the final state.
Catalytic properties of CeO2/TiO2 synthesized by different methods towards the organic dye photodegradation and NH3 selected catalytic removal of NOx
Authors: Ning Deyang , He Jiaxiong , Li Junqi , Liu Zuoyu , Liao Renjie , Lan Yuanpei , Wang Fan , Zou Zhou
Published: September 2023

In this work, three synthesis methods including photo-chemical, precipitation and hydrothermal were applied for synthesizing CeO2/TiO2 catalysts, and the catalytic performance including photodegradation degrees for organic pollutant and ammonia selective catalytic reduction (NH3-SCR) for NO removal were investigated. It was found that the photo-chemical synthesized CeO2-TiO2-PC exhibited the best photodegradation ability for methylene blue (MB), which had the degradation ratio of 91.21% and was approximately 23.92% higher than that with the matrix of rutile TiO2. The formed Ce-Ti heterojunction enhanced the separation of e
−/h
+ and further promoted the photocatalytic properties. Moreover, the CeO2-TiO2-PC, and the CeO2-TiO2-P which synthesized by the precipitation method showed better NH3-SCR properties than that of hydrothermal synthesized CeO2-TiO2-H below 300 °C, while the CeO2-TiO2-H owned an outstanding NH3-SCR performance above 300 °C. The difference on the NH3-SCR properties may be major attributed to the acid sites, pore structures and surface areas on the surface of different catalysts.
Design of a novel D-shaped SPR sensor with high sensitivity based on PCF for ultra-low refractive index detection
Authors: Luo Biyun , An Mengdi , Hu Tianqi , Jia Hongzhi
Published: September 2023

In this paper, a novel D-shaped plasmon resonance sensor based on photonic crystal fiber (PCF) is proposed to detect analytical materials with low refractive index. There are three arc-shaped small holes on both upper and lower edges of the fiber core, which can enhance the surface plasmon effect. The operation wavelength of the sensor is from 2243 nm to 2651 nm when its measurable refractive index range is between 1.17 and 1.27. The maximum spectral sensitivity of the sensor can be reached to 20 300 nm RIU−1, and the optimal resolution is 4.93 × 10−6 RIU. In our knowledge, the current literature indicates that when the refractive index is less than 1.3, this is the sensor with the highest spectral sensitivity among the reported low refractive index PCF-surface plasmon resonance sensors.
Fault Diagnosis of the LAMOST Fiber Positioner Based on a Long Short-term Memory (LSTM) Deep Neural Network
Authors: Tang Yihu , Wang Yingfu , Duan Shipeng , Liang Jiadong , Cai Zeyu , Liu Zhigang , Hu Hongzhuan , Wang Jianping , Chu Jiaru , Cui Xiangqun , Zhang Yong , Zhang Haotong , Zhou Zengxiang
Published: September 2023

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) has been in normal operation for more than 10 yr, and routine maintenance is performed on the fiber positioner every summer. The positioning accuracy of the fiber positioner directly affects the observation performance of LAMOST, and incorrect fiber positioner positioning accuracy will not only increase the interference probability of adjacent fiber positioners but also reduces the observation efficiency of LAMOST. At present, during the manual maintenance process of the positioner, the fault cause of the positioner is determined and analyzed when the positioning accuracy does not meet the preset requirements. This causes maintenance to take a long time, and the efficiency is low. To quickly locate the fault cause of the positioner, the repeated positioning accuracy and open-loop calibration curve data of each positioner are obtained in this paper through the photographic measurement method. Based on a systematic analysis of the operational characteristics of the faulty positioner, the fault causes are classified. After training a deep learning model based on long short-term memory, the positioner fault causes can be quickly located to effectively improve the efficiency of positioner fault cause analysis. The relevant data can also provide valuable information for annual routine maintenance methods and positioner designs in the future. The method of using a deep learning model to analyze positioner operation failures introduced in this paper is also of general significance for the maintenance and design optimization of fiber positioners using a similar double-turn gear transmission system.
Roles of the Indo-Pacific subsurface Kelvin waves and volume transport in prolonging the triple-dip 2020–2023 La Niña
Authors: Li Mingting , Cao Ziyang , Gordon Arnold L , Zheng Fei , Wang Dongxiao
Published: September 2023

The rare triple-dip 2020–2023 La Niña event has resulted in a series of extreme climate events across the globe. Here, we reveal the role of tropical Indo-Pacific oceanic interactions in driving the first triple-dip La Niña of the twenty-first century. Specifically, we found that the eastern Indian Ocean subsurface warming anomalies were associated with the re-intensification of the subsequent La Niña event. The subsurface warming anomaly signals were propagated eastward by equatorial and coastal subsurface Kelvin waves from the eastern Indian Ocean to the western Pacific Ocean through the Indo-Pacific oceanic pathway, which contributes to the accumulation of heat content and deepens the thermocline in the western tropical Pacific. The westward Indonesian Throughflow (ITF) transported more heat during multi-year La Niña events from the western Pacific Ocean to the eastern Indian Ocean than during single-year events, resulting in the injection of more warm water into the eastern Indian Ocean. The combination of subsurface Kelvin wave propagation and increased ITF volume transport in the Indo-Pacific region acted to prolong the heat content in the western Pacific during the decay phase of La Niña, ultimately leading to the rare triple-dip 2020–2023 La Niña event.
Finding the best path based on geographic information systems for transporting construction waste
Authors: Hameed A H , Rashid H A , Alhashemy A A
Published: September 2023

With the continued growth of the population, the activities resulting from this growth increased, especially urban expansion, which produced large construction waste. The random accumulation of this waste has turned into a global problem that cannot be ignored or postponed. Therefore, special landfills were established to transport the waste generated in any area to it, and because the cost of transportation depends the path that is taken directly, the best path had to be chosen. With the lack of scientific awareness of choosing the best path, this increased the cost of transportation, and here the need to intensify efforts and use technology to solve this problem. In this paper, the selection of the best path was studied. The field of study is in the city of Baghdad, where a specific building and two landfills approved by the Municipality of Baghdad were chosen. The required locations were obtained using (Google Earth) software, and the road network was downloaded with (QGIS) software, then (ArcMap) was used to determine the best path. As the first landfill was the closest in distance and the second was less in time. The study found that GIS technology is effective in the selection process and recommended the need to use GIS technology in construction waste management, and to install special steering devices on construction waste transport vehicles.
Applications of Super Critical Technology in Biodiesel Production
Authors: Shunaia Ahmed Ayad , Jazie Ali A.
Published: September 2023

Because of the scarcity of fossil fuels, it’s crucial to look into non-conventional options. In this context, “biofuel” refers to any fuel, liquid, gaseous, or solid, that is primarily derived from biomass. Many different types of biofuels exist, including ethanol, methanol, diesel, and hydrogen. Biodiesel, is a promising alternative fuel. It’s eco-friendly and manufactured from edible or nonedible oils. Transesterification, non-catalytic supercritical fluid technique, micro emulsion, pyrolysis, and other methods have all been recorded for producing biodiesel from vegetable oil and lipids. This article compares and contrasts the advantages of using conventional catalytic processes to produce biodiesel with those of using supercritical fluids (SCF). Concerns have been raised regarding the substantial amount of energy that must be expended in order to carry out supercritical reactions under conditions of high pressure and temperature. This is despite the fact that the catalyst-free SCF method clearly offers a number of benefits that are hard to ignore. Because of this, the SCF process has significant difficulties that need fixing before it can become a long-term viable technology.
Assessment of Biological Trickling System with Different Layers of Material for Grey Water Treatment
Authors: Abbas Ebtesam K. , Ali Seroor Atalah K.
Published: September 2023

Greywater reuse is an attractive alternative whenever water resources are scarce because it can lower water demand and increase available water supply. This study used simple, easy-to-find treatment and purification methods to examine how gray sewage from homes could be used in agriculture. The primary motivation for reducing agricultural fertilizer consumption is financial gain. If feasible, society can achieve more acceptable economic objectives. The multimedia biofilter, a biological trickling filter, treats wastewater biologically by attaching biomass to various media. In this investigation, raw greywater was settled for two hours. The same influent was used to compare and contrast two treatment approaches. The treatment methods include an exploration of the effectiveness of two filters. The first filter comprises sand, gravel, cotton, and activated carbon filtration layers. The second contains sand, gravel, brick bat, wood chips, and rice husk filtration layers. Gray water was purified utilizing a sand filtration system (gravel and sand), along with the addition of other materials to improve the effectiveness of the treatment. These additional materials included cotton, active carbon, brick, wood chips, and rice husks. Chemical tests were performed on the graywater, and each component was identified. Overall, the sand-gravel-cotton-activated carbon filter improved greywater quality to irrigation standards by reducing organic matter. The second filter (made of sand, gravel, brick, wood chips, and rice husks) is a low-cost greywater recycling unit. But there is still room for improvement in how well these filters work with higher and changing loads and how long their materials last. As a result, most of the filter materials used were waste products generated inside homes and are said to be the least expensive and most inexpensive filters.
Performance Evaluation of conventional Sewage Treatment Plant, Iraq
Authors: Hantoush Noor Kareem , Ghawi Ali Hadi
Published: September 2023

One of the most pressing challenges facing contemporary health is the purification of drinking water and wastewater. Pollutants in wastewater are among the most widespread in the environment, and there is a broad spectrum of detrimental impacts associated with untreated or badly treated wastewater. The current research assessed the efficacy of the Al Rumaitha wastewater treatment facility in Muthanna province, Iraq, in eliminating municipal pollutants according to national standards. Pollutant characteristics were measured using samples taken both from the plant’s raw wastewater intake and its finished treated water output. These parameters are the Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solids(TSS), Ammonia (NH3), Phosphorus (PO4), and the quantitative measure of the acidity or basicity (pH). According to the results, all analyses of collected samples of the plant’s effluent met the Iraqi water quality standards(IWQS) for pH, COD, BOD5, and TSS, whereas the values of NH3 and PO4 did not reach the (IWQS) in all months. where mean monthly removal efficiencies of 86% for BOD5, 80% for COD, 93% for TSS, 39% for PO4, and 27% for NH3 were achieved. Briefly, it can be said that the Al-Rumaitha WWTP has an acceptable level of efficacy in treating wastewater for some of the examined parameters and providing water in line with Iraqi environmental regulations, but not for others.
Shear strength of recycled aggregate concrete beams without shear reinforcement
Authors: Merdas Huda S. , Shallal Muhaned A.
Published: September 2023

Steel fibers have recently become increasingly popular for strengthening reinforced concrete members. This research contains a study of shear strength under the effect of replacing 50% of natural coarse aggregate (gravel) with recycled aggregate (crushed brick) as well as the effect of steel fibers for natural aggregate concrete and recycled aggregate concrete. Five concrete beams with dimensions of 2000 mm in length, 300 mm in depth, and 200 mm in width were tested to evaluate the effect of recycled aggregates and to evaluate the efficiency of steel fibers in improving the shear capabilities of concrete beams. Beams are designed to fail due to shear stresses (without shear strengthening). The specimens were reinforced with four 4" X 16" steel bars at the bottom and two 2" X 10" steel bars as top reinforcement. Three volumetric fractions of steel fibers were used: 0%, 0.5%, and 1%. The samples were subjected to a two-point loading test. The beam samples have a ratio of shear span to effective depth (a/d) equal to 2. The results showed that replacing 50% of natural aggregate with recycled aggregate decreased ultimate shear strength, but adding steel fibers by 1% by volume resulted in an increase of 31.8% in shear strength for a recycled concrete beam. For ordinary concrete, the final shear strength increased by 18.3% and 30.8% when steel fibers were added by 0.5% and 1%, respectively. Moreover, the results also showed that the failure mode of all samples is the shear failure mode.
Repairing and strengthening techniques of RC beams: a review
Authors: Hassan Rafea F. , Latief Ammar Fawzi
Published: September 2023

The purpose of this review is to present the techniques for strengthening or repairing of reinforced concrete-beams (RC). The concrete members, like RC beam are might be required to be strengthened to increase the internal strength capacity to resist additional external loads or repaired to increase the design’s structural rigidity and insulate the reinforcement from aggressive conditions. The experimental studies that related to the techniques of repairing and strengthening of RC beams using: external steel plates, fiber reinforced concrete (FRC), reinforced concrete (RC) jacketing, sprayed fiber reinforced polymer FRP, epoxy injection, mortar jackets, near-surface carbon fiber (SNSM-CFRP) strips, near-surface glass fiber (NSM-GFRP) rods, CFRP laminate and sheet; and adding an ultra high performance concrete (UHPC) layer. All the techniques that were discussed showed that there is an improvement in the general behavior of the beams that have been strengthened and repaired, as well as an increase in the maximum load and ductility.
Review of retrofitting techniques of deteriorated reinforced concrete columns
Authors: Kadhim N J , Al-Ramahee M A
Published: September 2023

To ensure sustainability, all types of building structures should be kept in accepted condition throughout their life of service. Rehabilitation has been the subject of extensive research recently because of rising spending on construction and maintenance of constructed infrastructure. The most recent methods to reinforce current reinforced concrete columns, including both conventional and cutting-edge strengthening procedures, are presented in this study. Frequently, general materials used in repairing on-service reinforced concrete columns are concrete, steel, and different kind of Fiber Reinforced Polymer (FRP) composites. Conventional methods and procedures for different mode of failures strengthening, including all types of FRP procedures Near Surface Mounting (NSM) reinforcement, Externally Bonded (EB) FRP, and textile reinforced concrete will all be included in the discussion, and FRP pre-stressing methods for modifying existing structures.
Behaviour of reinforced concrete corbels strengthened by FRP composites and steel bars: a critical review
Authors: Al-Kaabi Nawras H , Al-Thairy Haitham , Dhaheer M S Abo
Published: September 2023

In reinforced concrete (RC) structures, corbels that extend from the faces of reinforced concrete columns are commonly employed to support primary beams and girders. Frequently, the use of corbels is limited to cantilevers with a shear span-depth ratio that is often less than 2. Because of this relatively low ratio, corbel strength is normally dominated by shear, which is comparable to deep beams. However, owing to some reasons (e.g., design and/or construction faults, modification of facility use, deterioration, and aging), strengthening of existing corbels is becoming of prime importance. The aim of the present paper is to conduct a critical review of commonly proposed techniques that have been implemented to strengthen RC corbels. These techniques comprised near surface mounted (NSM) steel bars, NSM fibre reinforced polymer (FRP) bars, and FRP sheets. The latter strategy included carbon (CFRP) and glass (GFRP) sheets. Hybrid strengthening (combining FRP sheets and FRP/steel bars) was also highlighted in this paper. The strengthened (upgraded) RC corbels were evaluated considering several parameters, including shear span to depth ratio (a/d), quantity and configuration of reinforcement, FRP type, and levels of damage in the tested specimens.
Torsional behaviour of RC beams strengthened by NSM GFRP bars
Authors: Al-Ziady A C , Al-Thairy Haitham
Published: September 2023

Near-surface mounted (NSM) fiber-reinforced polymer (FRP) reinforcement is an innovative, serviceable, and beneficial method for strengthening reinforced concrete (RC) structures. Previous studies have proven that the epoxy-resin bonded NSM FRP method effectively achieved shear and flexural strengthening. However, only a few researches have employed this technique for improving torsion but, no research has been conducted on the use of NSM with GFRP bars and epoxy adhesives. This study investigates the behavior of RC beams subjected to combined torsion when they have been enhanced with NSM GFRP U-shaped and closed stirrups with different overlap sites. Four RC beams with dimensions of (150×250×2000) mm (width X depth X length) were considered in the experimental tests. One RC beam is not strengthened and used as a control beam (CB), while three beams are enhanced with NSM GFRP bars in different shapes and overlap configurations. The findings of the tests in terms of twist angle_applied torque curves, the torque of initial cracking, the ultimate torsional carrying capacity, and the ultimate angle of twist were all recorded and evaluated. It has also been shown that a considerable improvement in the performance of RC beams in twisting can be achieved by using NSM GFRP stirrups. From the different NSM strengthening configurations used in the tests, results have demonstrated that beams strengthened by closed GFRP stirrups at the opposite overlap with 100 cm spacing outperformed other strengthened beams of about 181.5% compared to the CB. In contrast, the beam, strengthened by U-shaped GFRP stirrups with spacing at 200 cm, had the lowest torsional strength of about 48.1% relative to the CB.
Assessing of sustainable construction quality in Iraq under conditions of risk factors
Authors: Abramov I L , Alzaidi Z A
Published: September 2023

The area generally and Iraq specifically suffers in the current period from a lot of political and economic conditions which leads to the emergence of many risk factors and uncertainty in construction projects. In addition to the nature of the climate and the lack of organizational and technical programs and scheduled and continuous preventive maintenance programs in addition to the risks of terrorism and wars. The aim of the study is to assess the extent of the impact of various risk factors on construction facilities and roads for the purpose of increasing the ability of those facilities to confront these risks through managing them and applying selected criteria from the elements of sustainable construction. A questionnaire was prepared to identify the risk factors that may exist in building and construction projects, and after the risk groups were identified through the questionnaire form and personal interviews with the project participants, those groups were analyzed using the structural equation model in the program (PLS -SEM). The results showed that the ecological, economic, political, technical and social risk factors have a clear impact on the quality of sustainable construction of infrastructure projects in Iraq, and thus a clear influence on the project objectives (cost, duration and quality).
The Effect of Using Various Types of Mineral Fillers on Moisture Damage of Hot Mix Asphalt
Authors: Al-Shabani Zainab J. , Obaid Ihsan A.
Published: September 2023

In general, asphalt additives are designed to improve the performance of asphalt mixtures by increasing their durability and resistance to cracking, and other forms of damage. Asphalt additives can be made from natural or synthetic materials, and some are biodegradable. Natural asphalt additives such as steel slag powder and silica fume are generally more sustainable than synthetic ones. The use of sustainable asphalt additives can help reduce the environmental impact of asphalt mixtures while improving their performance. This study aims to evaluate the effects of various fillers on the performance of the asphalt mixture and its tolerance to moisture damage, including steel slag powder, silica fume, and ordinary Portland cement. The research involves establishing a standard reference mix for comparison as well as several asphalt mixtures with varying amounts of mineral fillers (0, 25, 50, and 75% SSP and 3, 6, and 9% SF & OPC). The Marshall stability tests and the indirect tensile strength test were among the tests used to evaluate the mechanical properties, and the results showed that the optimal value for using steel slag powder is (25%) and for silica fume is (9%).
Eco-friendly concrete produced with recycled materials
Authors: Abeer S Z , Hasan Zaid Ali , Karim Abbas Bashar , Hassan Dhay Abdallah , Jabr Dhurgham Naeem
Published: September 2023

Using recycling materials to produce concrete become a major subject for research in the last decades. The work aims to examine the effects of the partial replacement of fine aggregate by recycled rubber. In addition to studying the influence of two different fiber types on mechanical properties of concrete with rubber replacement. Three types of rubbers that differ in particle size are used to find the effect of rubber particle size on compressive strength, splitting tensile strength, and flexure strength of the concrete mix. Two waste fiber types are used which are Rope Waste Fiber (RWF) and Steel Waste Fiber (SWF). The findings showed that minimizing the rubber particle size improved the mechanical properties. Also, using two types of waste fiber (rope and steel) together led to improve compressive strength.
Risk Assessment of the main transport corridor in Iraq
Authors: Shokat Doaa M. , Jameel Abeer Khudhur
Published: September 2023

The increased rate of road fatalities ad injured has been a vital issue. Risk assessment of road project is essential in the planning and design stages to prevent road crashes occurring in the operational stage. In Iraq, the main transport corridor has been designed to connect major cities and used by significant traffic volume which led to increase in the crash fatalities. Therefore, it is important to identify the risk factors and improve the safety level. This paper aims to assess the risk of part of the main transport corridor in Iraq. The selected section is part of Road 9 which connects Abu Gharib district with Fallujah City. The selected methodology of assessment is based on the road features and supported traffic data developed by the International Road Assessment Program (iRAP) agency. The output of the assessment is in terms of star rating and star rating score. Higher star rating means safer road condition while higher star rating score means more dangerous road condition. The results of assessment show high level of risk for vehicles. A set of road improvements that meet safety standards are proposed such as improving delineation, lighting, Metal barriers for the median, central strips, intersection channelization, Various repairs according to the severity of the damage at pavement and using shoulder rumble strips. The results of assessment after improvements show upgrading the star rating to the recommended minimum (3 and 4 stars) for vehicles.
Evaluation of Speed, Flow, and Density Performance under Different Severity of Speed Bumps
Authors: Aboud G M , Khaled T T , Taher E S , Hashim I N , Al-Humeidawi B H
Published: September 2023

Speed bumps are effective traffic calming tools that give transportation experts the ability to regulate vehicle speeds and enhance safety in particular areas. Despite being often utilized in populated areas, they are more common on other, busier roads (especially in developing nations), thanks to their efficiency, low cost of implementation, and simple installation procedure. Numerous speeds, flow, and density relationship hypothesized in various studies are supported by empirical data gathered in favorable circumstances. Because the graph is not a function, those who delved into comparison study under diverse situations frequently employ forced curves to demonstrate how flow and speed are related. However, the research makes an attempt to hypothesize that the behavior of dynamic speed-flow, speed-density, and flow-density functions is identical. In the study, the link between speed and flow under different severity speed bumps. The current study’s main objective is to is to quantify traffic volume and speed according to controlled conditions before comparing them to unfavorable speed bumps conditions of varying severity: low SB1, medium SB2, and high SB3. To determine the link between the traffic characteristics, the Greenshields model is used. The study show that decrease in speed from 66.6 km/h (control section speed) to 39.4 km/h, which is equivalent to a drop in speed of about 40%. SB2’s moderate severity bumps on traffic volume, speed, and density caused the flow rate to drop to 1236 vph and the free flow speed to drop to 28.2 km/h. While SB3’s high intensity bumps had an impact on traffic characteristics, the study show that the maximum value of speed is 5.34 (km/h), which equates to an hourly traffic flow of 816 cars.
Changes in Groundwater Levels and its Salinity (Badra Basin Iraq)
Authors: Rdhewa A M , Karim I , Mohammed Z B
Published: September 2023

A fact that human-induced greenhouse gas emissions have led to an increased frequency and/or intensity of some weather and climate extremes since pre-industrial time, in particular for temperature extremes which affected lots of regions by reducing precipitations. Accordingly, this reduction causes a lowering of groundwater levels which was adopted as a goal of this study and its effects on quality of it. The study area is Badra - Jassan basin located to the north of Kut city, the center of Wasit governorate, and bordered by the international boundary with Iran from the east and northern east covering an area of about (1020) Km2. Badra - Jassan basin is an important hydrogeological basin in which groundwater can be used for agricultural purposes; especially with decreasing surface water supply. The research studied a predictive mathematical model of groundwater by ten wells distributed randomly within the boundaries of the study area; all of them fall within the unconfined aquifer the mathematical model for the study area has been developed using the Geographic Information System (GIS) software. The Groundwater level map for the ten existing wells was drawn from data in (2021) and a comparison with else published in (2002) for the study area. Likewise, the salinity concentration map variations for the same periods were estimated. The present study showed a decline in groundwater levels which conjunction with an Increasing in the range and value of groundwater salinity concentrations.
Electrocoagulation process as an alternative treatment of petroleum industry liquid waste and renewable energy sources
Authors: Pratiwi R , Chusniyah D A , Fajarwati K , Fadliah  , Satiawati L
Published: September 2023

Industrial wastewater treatment technology that is environmentally friendly and renewable energy are two critical issues that have not been resolved. Electrocoagulation technology offers a liquid waste treatment process that simultaneously produces hydrogen gas as a renewable alternative energy source. In this study, an attempt was made to observe the ability of the electrocoagulation process to remove pollutants from the wastewater of the petroleum industry, which is represented by a phenol solution. Meanwhile, electrocoagulation also produces hydrogen gas along the process. Based on observations solution’s pH, voltage and processing time, it was found that the optimal conditions for processing liquid waste containing phenol were obtained by using voltages of 20 volts in a waste solution with a pH 10. The process was carried out within 3 hours. The obtained phenol removed 22 % and hydrogen gas as much as 123.31 mmol/m2 at the end of the process. The development of this process is considered quite intriguing to utilize wastewater treatment as a new renewable energy source.
Application of response surface methodology (rsm) for optimisation of cod removal from tofu wastewater in an adsorption process using silica adsorbent
Authors: Hardyanti N , Susanto H , Budihardjo M A , Purwono Purwono , Saputra A T
Published: September 2023

The entry of pH, turbidity, COD, and TSS pollutants from tofu wastewater decreases discharge water quality and may affect the discharge water treatment process. This study aims to find variations in the mass and size of silica and the optimum adsorption time on the removal efficiency of pH, turbidity, COD, and TSS from tofu wastewater using silica adsorbent with applying surface response methodology. Chemical treatment was carried out to meet turbidity, COD, and TSS parameters. The research method used a laboratory-scale batch system with adsorbent size, mass, and adsorption time variations. From the research conducted, it obtained that the best removal for the pH test was the 100 mesh silica variation in the treatment of 3.295 gr with an adsorption time of 37 minutes; the pH value after removal was 4.87, for the turbidity test was 80 mesh silica variation in the treatment of 10 gr with an adsorption time of 15 minutes and the turbidity value after removal was 114 NTU, for the COD test, the best removal was obtained from a variation of 8.74937 gr of 104,342 mesh size silica at 39.0248 minutes of contact time with a COD value after removal of 851.33 mg/l, then for the TSS test was the 80 mesh silica variation in the treatment of 10 gr with an adsorption time of 59 minutes and the TSS value after removal was 65 mg/l.
Aluminium recovery from aluminium foil waste as coagulant for domestic wastewater treatment
Authors: Mahmudah L , Juliastuti S R
Published: September 2023

The high use of aluminium foil in food and beverage packaging has caused solid waste to increase rapidly, so solid waste treatment is required. This study investigates the best concentration of reactant to aluminium recovery from aluminium foil waste as potash alum coagulant. Potassium hydroxide is used for dissolved aluminium, and sulphuric acid is added to form potash alum crystals. The experimental result got a maximum point for the synthesis of potash alum from aluminium foil: potassium hydroxide 3 M dan sulphuric acid 3 M which produced a potash alum yield’s 99,59% and contains 11,19% of aluminium oxide. The quality of potash alum products is compared to the technical requirements of SNI 0032:2011. Potash alum was applied to the domestic wastewater and compared with commercial alum. The turbidity, TSS, and TDS domestic wastewater treatment results showed that potash alum has better performance than commercial alum.
Development of emission reduction measures of trace gas emissions from coal-fired power plants in Indonesia
Authors: Kusuma S A P , Permadi D A , Dirgawati M
Published: September 2023

Most of Indonesia’s electricity demand is supplied by coal fired power plants (CFPPs) which can potentially emit huge amounts of air pollutant gases such as NOxand SO2gas. The country has committed to reduce Greenhouse Gases (GHGs) emission by 2030 through Nationally Determined Contributions but some emission reduction measures may also reduce air pollutant gases. Flue Gas Desulfurization (FGD) and Atmospheric Fluidized Bed Combustion (AFBC) are the leading control technologies for reducing SO2and NOxemissions that can be installed in the CFPPs. This study aims to determine the pollution load of SO2and NOxgases in 2030 generated from CFPPs operation with (reduction scenario) and without FGD and AFCB control technology (business as usual (BAU)). The gas pollution load was calculated using the Atmospheric Brown Clouds- Emissions Inventory Manual (ABC-EIM) procedure. Based on the BAU scenario, the emission load accounted of 1,440,192 tons/year for NOxand 613,121 tons/year for SO2in 2030. After implementing the control technology scenarios in 2030, the NOxemission load is projected to decrease to 579,610 tons/year, and the SO2emission load decrease to 77,920 tons/year. The application of AFBC and FGD control technologies can potentially reduce NOxand SO2emissions load from CFPPs operation in 2030 thus it can help to improve air quality in the future.
Analyzing the performance of cyclones and scrubbers as air pollution control methods for household solid waste incinerator
Authors: Khair H , Nur T B , Suryati I , Utami R , Surya K D
Published: September 2023

Household solid waste processing through incinerators may pose environmental problems, as gas emissions from combustion are released. Air Pollution Control Devices (APCD), such as cyclones and cyclone scrubbers, are frequently utilized to mitigate these issues. This study aims to evaluate the efficacy of cyclones and cyclone scrubbers as APCD for incinerators. To conduct the study, gas emissions for the parameters SO2, NOx, and CO were measured from the combustion of mixed waste in an incinerator with a fixed waste composition. Data were collected every 5 minutes within 45 minutes of combustion at the inlet and outlet of each APCD. The results indicate that using a cyclone can eliminate 37% of NOx and 91% of CO emissions. In contrast, a cyclone scrubber can remove 53% of NOx and 96% of CO emissions. Notably, the gas analyzer failed to recognize the SO2 parameter. Implementing a cyclone can reduce gas emissions from incinerator combustion, and combining a scrubber within the cyclone can increase its effectiveness in reducing these emissions.
Conceptual design of floating storage and regasification unit (FSRU) for Eastern Part Indonesia
Authors: Khoiriyah Lilik , Artana Ketut Buda , Dinariyana A A B
Published: September 2023

Liquefied Natural Gas (LNG) can be used as an alternative fuel with environmentally friendly solutions. In general, the domestic distribution of natural gas in LNG is more cost-effective than transporting gas through underwater pipelines considering Indonesia as archipelagic country. According to Indonesia’s Minister of Energy and Mineral Resources Regulation Number 13 of 2020, the government supports converting 52 power plants to LNG. However, the current challenge in the LNG industry is the lack of supporting facilities. Storage and regasification facilities are among the infrastructure that requires optimization. Floating Storage and Regasification Unit (FSRU) are viable options for energy distribution that offer opportunities and competitiveness compared to onshore terminals. Small and medium-scale FSRU can serve as an alternative solution due to their relatively fast, flexible, and affordable development process. Therefore, this research will develop a small-medium FSRU design with a capacity of 60 MW − 70 MW in Eastern Indonesia. FSRU design should consist of four segments including location considerations and environmental conditions, powerplants gas requirements, LNG storage tank sizing and LNG regasification process. Calculations for various supporting FSRU components, seakeeping analysis, loading-offloading processes, 3D modelling and the integration of solar panels were discussed. The results obtained include the principal dimension, technical aspects of FSRU design, and the technology for LNG regasification processes used.
Smart Evaluation of Green Campus Sustainability at Universitas Negeri Jakarta
Authors: Zulfa V , Nugraheni P L , Mashabi N A , Faesal M
Published: September 2023

This study aims to identify models of environmental sustainability and Green Campus within the Faculty of Engineering, Universitas Negeri Jakarta. This study used research and development method. The data collected in this study is primary data consisting of respondent characteristics, environmental sustainability, and Green Campus characteristics in the Faculty of Engineering, Universitas Negeri Jakarta. The population in this study were all students of the Faculty of Engineering, Universitas Negeri Jakarta. The sample in this study was all students of the Family Welfare Cluster. Data was collected by filling out a questionnaire. The data that has been collected is then processed and analyzed to see the most appropriate environmental sustainability and Green Campus model to be applied in the Faculty of Engineering. The research stages consist of research preparation, theory review, instrument preparation, instrument testing, instrument revision, field data collection, processing data, data analysis, and preparation of research outputs. Green Campus model in Universitas Negeri Jakarta focuses on the existence of green space, transportation, and the green movement. The concern is needed from various parties to strengthen other components in the section on green energy, green people, and green transportation. Policies are needed to move the academic community to be more concerned about the campus environment and the future development of Universitas Negeri Jakarta.
Briquettes Optimization of Palm Shell Waste and LDPE Plastic based on Particle Size and Compressive Strength as Alternative Fuels
Authors: Dalimunthe Y K , Widayani  , Aditya I D
Published: September 2023

The purpose of this study was to find the optimal parameters of the briquette making process (particle size and pressure), where optimization was carried out based on the values of physical properties, namely density, elastic modulus and ultimate tensile strength. The method used in this study was to vary the particle size of palm shell charcoal waste with particle sizes of 40, 60, 80 and 100 mesh mixed with chopped LDPE plastic with a size of 0,5 x 0,5 cm, starch adhesive and water with a predetermined composition, then the briquettes are given varying pressures of 30N/m2, 40N/m2, 50N/m2, 60N/m2, 70N/m2 and 80N/m2. The results of this study found that the highest density value was 808,71 kg/m3, the highest elastic modulus value was 50 MPa, and the highest ultimate strength is 4,81 Mpa. Based on the values of density, elastic modulus and ultimate tensile strength, it can be concluded that the most optimal briquettes are produced from a particle size of 80 mesh and a pressure of 70N/m2 with a density value of 796,08 kg/m3, an elastic modulus of 40 MPa and an ultimate strength of 4,81 MPa.
Energy and CO2 saving potential of district heating system
Authors: Kadric Dz , Biber N , Omanovic A , Kadric E
Published: September 2023

This paper presents the energy and CO2 saving potential of existing district heating energy system. Analysed system fully rely on fuel oil, with significant energy losses, increased fuel consumption and CO2 emission resulting from outdated and oversized system and fuel with high greenhouse emission factor. Heat generation and thermal energy distribution systems efficiency are assessed, showing that overall system efficiency is 48.5%. System environmental impact is shown via absolute CO2 and specific CO2 emission per heated surface area and useful energy. The study proposes retrofit measures to improve system efficiency, reduce fuel consumption, introduce low-emission fuels, and lower the system’s environmental impact. The study finds that the implementation of these measures could reduce system energy consumption by 42.7%, absolute CO2 emissions by 52%, and specific CO2 indicators as well, highlighting the potential for reducing the environmental impact of district heating systems while meeting users energy needs.
The economic feasibility approach of the development of geothermal power plant 2 x 20 MW
Authors: Timpal G B J , Irham S , Yulia P S
Published: September 2023

The development of a geothermal power plant project can be implemented if the project is feasible and can provide benefits from the economic side. In this study, the economic feasibility calculation for the development of a 2 x 20 MW power plant project was carried out based on economic indicators such as Net Present Value (NPV), Internal Rate of Return (IRR) and Pay Out Time (POT). The discounted cash flow method is used in determining the economic feasibility. The calculation results obtained for this power plant development project is not feasible because the NPV is US$ -31,336 million, IRR is 7.11% and POT is 0 year. Due to the uneconomical results obtained, a sensitivity analysis was carried out on the tariff price, drilling costs, and Engineering, Procurement, Construction, and Commissioning (EPCC) costs. With electricity tariffs regulated based on Presidential Regulation Number 112 of 2022, it is found that the resulting taxes in the area are not economical and there is needed for tariff adjustments, namely at a minimum price of 15 cents/kWh and 18 cents/kWh so that the project is economical. However, this price could not be realized because the price far exceeded the highest benchmark price set. Meanwhile, with these uneconomical and unfeasible results, a scenario of a loan was carried out to get better results with an NPV is US$ 528,000, IRR is 10.46% and POT is 28 years. Therefore, with a loan scenario, the project can be obtained as feasible.
Encapsulation Of β-Carotene And Curcumin In Liposome From Soybean Lecithin And L-α-Phosphatidylcholine Using SC-CO2 With The Assistance Of Ultrasonication
Authors: Safitri A , Machmudah S , Winardi S , Wahyudiono
Published: September 2023

The newest method to maintain better bioavailability of antioxidant compounds in the human digestive process is encapsulation using liposomes. The liposomes used were lecithin from soybean seeds and L-α-Phosphatidylcholine. Furthermore, curcumin and β-carotene were encapsulated in soy lecithin liposomes using SC-CO2 with 100% ethanol, aquadest 50% v/v ethanol and 100% aquadest at 50°C, 60°C, and 70°C and pressure 15 MPa, 20 MPa and 25 MPa by ultrasonication for 60 minutes. This research was conducted to obtain liposomes from curcumin and β-carotene encapsulation, analyse the effect of lecithin from soybean seeds on the formation of encapsulation in liposomes, analyse the effect of operating conditions on the encapsulation process on the size of curcumin and β-carotene in liposomes and determine the size characteristics of liposomes. This was analysed using a UV-Vis Spectrophotometer and Particle Size Analyzer (PSA) with the Dynamic Light Scattering method and also using the Scanning Electron Microscope (SEM) method. The results of the PSA test showed that the increase in operating temperature and pressure resulted in an increase in liposome particle size. UV-Vis analysis proved that the content of curcumin and β-carotene in liposomes from L-α-Phosphatidylcholine had better results. It was found that using SC-CO2+Sonicator had higher concentrations of curcumin and β-carotene with the condition that the higher the temperature, the higher the curcumin content. The use of liposomes has increased the stability of encapsulated suspensions and prevented flocculation. SEM analysis proved that the encapsulation of curcumin with L-α-Phosphatidylcholine has the smallest particle size distribution of 2 micro meters so that it can be categorized as multilamellar vesicles (MLV).
Transit, walking and cycling infrastructure and sustainable development in Enugu city, Nigeria
Authors: Okosun Andrew E. , Okeke Francis O. , Igwe Ajuluchukwu E. , Ezema Emmanuel C.
Published: September 2023

In a predominantly urban world, people’s ability to move within cities is a critical driver of sustainability. The transportation system which constitutes a large percentage of the physical urban environment provides mobility and aid economic sector. However, it contributes to several major environmental pressures including pollution, congestion, accidents, waste accumulation, resources depletion and disruption of nature. While urban population growth and increase in economic activities combine to generate higher demand for transportation services and heighten the problem. How to effectively deal with these imposing threats and simultaneously provide optimal mobility for city dwellers is the backbone of this research. Drawing experiences from developed cities, the study used Achara layout in Enugu as a case study. From observation, surveys and published literature data were collected and analysed qualitatively. The primary data include, physical traffic count, existing road character, traffic infrastructure and demographic statistics. Findings show the extensive sterility of Enugu’s urban infrastructure to motorized traffic and lack of provision for walking and cycling. It recommends strategies for planning and managing the urban environment which recognizes and acknowledged the social, environmental and economic realities. The conclusion demonstrates that cities designed for pedestrians and cyclist are cities designed for people and sustainable development.