Passive Method Research Articles

Integrated assessment of heavy metal pollution in the great bačka canal: Comparing active and passive sampling methods.

This study investigates the environmental risks posed by heavy metals in sediment from the Great Bačka Canal using both active and passive sampling methods. The necessity of this research lies in the critical need to address sediment contamination in ecological hotspots and enhance sediment management practices. Active sampling revealed total heavy metal concentrations, while sequential extraction showed bioavailability varied across metal fractions. Passive sampling with SPeeper™ quantified freely dissolved metal concentrations in sediment pore water, identifying zinc (41μg/L) as the most bioavailable metal. Risk indices, including Igeo (geo-accumulation index) and IWCTU (interstitial water criteria toxic units), revealed low to moderate contamination levels. Although copper content classified the sediment as extremely polluted (195.7mg/kg), its low bioavailability (16μg/L in pore water) mitigates immediate ecological risks. These findings emphasize the importance of integrating passive sampling in regulatory frameworks for a realistic environmental risk assessment of sediments.

Microfluidics Based Particle and Droplet Generation for Gene and Drug Delivery Approaches.

Microfluidics-based droplets have emerged as a powerful technology for biomedical research, offering precise control over droplet size and structure, optimal mixing of solutions, and prevention of cross-contamination. It is a major branch of microfluidic technology with applications in diagnostic testing, imaging, separation, and gene amplification. This review discusses the different aspects of microfluidic devices, droplet generation techniques, droplet types, and the production of micro/nano particles, along with their advantages and limitations. Passive and active methods for droplet formation are discussed, as well as the manipulation of droplet shape and content. This review also highlights the potential applications of droplet microfluidics in tissue engineering, cancer therapy, and drug delivery systems. The use of microfluidics in the production of lipid nanoparticles and polymeric microparticles is also presented, with emphasis on their potential in drug delivery and biomedical research. Finally, the contributions of microfluidics to vaccines, gene therapy, personalized medicine, and future perspectives are discussed, emphasizing the need for continuous innovation and integration with other technologies, such as AI and wearable devices, to further enhance its potential in personalized medicine and drug delivery. However, it is also noted that challenges in commercialization and widespread adoption still need to be addressed.

Implementation Of Flow Control Methods For Design Of Connecting Duct Of Annular Sector Cascade Tunnel

Abstract The present study discusses the effect of various flow control methods implemented to develop an Intermediate Turbine Duct (ITD), providing a continuous flow path between the contraction duct of the wind tunnel and the annular sector cascade (ASC) test section to deliver the required flow. The S-shaped diverging passage of the ITD with continuously increasing mean radius imposes a major challenge to achieving the required inlet flow angle with periodicity at the entry of the ASC. The numerical study was performed in ANSYS CFX® to analyze the effect of active and passive flow control methods on the ITD exit flow delivered to the ASC test section. It was found that Inlet Guide Vanes (IGVs), incorporated within the ITD as a passive flow control method, direct the flow through ITD, and approximately required inlet flow condition with reasonable periodicity was achieved at the entry of the ASC test section. However, the opening slot on the casing endwall, an active flow control method, shows the adverse effect on the flow angle distribution at the entry of the ASC test section. The change in axial spacing between IGVs and the test vane cascade shows a negligible effect on the cascade entry flow field. The experimental flow field measurement performed using a five-hole pressure probe showed that IGVs successfully directed the flow through the ITD, precisely meeting the requirements at the test section. The surface oil flow visualization confirms the formation of various flow features captured in the computational study.

ANALISIS TEKNIS DAN EKONOMIS PADA PENGELOLAAN AIR ASAM TAMBANG MENGGUNAKAN KAPUR TOHOR DI KPL 01 AL CIK AYIB PT BUKIT ASAM, Tbk.

This research aims to analyze the management of acid mine drainage (AMD) using quicklime at KPL 01 CIK AYIB PT Bukit Asam, Tbk. from technical and economic perspectives. The research method used is descriptive quantitative with primary data collection through field observations and secondary data from the company. The results show that AMD management at the site uses an active method with the addition of quicklime (CaO) in the first 5 compartments, followed by a passive method using wetlands in the next 9 compartments. The average use of quicklime is 6 sacks (180 kg) per day, capable of neutralizing the pH of AMD from 5.5 to 6.69-8.21 at the outlet. The cost of using quicklime for one month reaches Rp 8,865,000. This study concludes that AMD management using quicklime at the site is technically effective in neutralizing pH according to quality standards and needs further analysis in terms of its economic efficiency.

Ring‐in‐Ring Assembly Facilitates the Synthesis of a [12]Cycloparaphenylene ABC‐Type [3]Catenane

AbstractCycloparaphenylenes (CPPs) represent a significant challenge for the synthesis of mechanically interlocked architectures, because they lack heteroatoms, which precludes traditional active and passive template methods. To circumvent this problem and explore the fundamental and functional properties of CPP rotaxanes and catenanes, researchers have resorted to unusual non‐covalent and even to labor‐intensive covalent template approaches. Herein, we report a ring‐in‐ring non‐covalent template strategy that makes use of the surprisingly strong non‐covalent inclusion of crown ethers into suitably sized CPPs. By threading a secondary ammonium salt through the crown ether and closing the third ring via CuAAC click reaction, we obtained a rare ABC‐type hetero‐[3]catenane comprising [12]CPP, 24‐crown‐8 and a dibenzylammonium macrocycle. X‐ray crystallography shed light on the ring‐in‐ring pre‐organization and the [3]catenane topology was confirmed by NMR and MS‐MS studies. Molecular simulations provided insights into the intriguing ring‐vs.‐ring‐vs.‐ring dynamics of the [3]catenane, which are highly dependent on the protonation state of the dibenzylammonium site. This ring‐in‐ring assembly strategy opens new avenues for the synthesis of complex CPP architectures and their use in functional supramolecular systems.

Detection of Manipulations in Digital Images: A Review of Passive and Active Methods Utilizing Deep Learning

Detection of Manipulations in Digital Images: A Review of Passive and Active Methods Utilizing Deep Learning

Techniques for Evaluating Airborne BiocrustDiaspores: From Fundamentals to Advanced Approaches

Biological soil crusts (biocrusts) are communities which thrive primarily in the upper soil layers of arid and semi-arid environments. Biocrusts produce soil-binding compounds, tolerate extreme conditions, and disperse through both sexual and asexual diaspores via wind, water, or animals. Despite their significance, dispersal mechanisms involving airborne diaspores in biocrusts remain largely unexplored and poorly understood. This review provides an overview of techniques, from basic to advanced, to help researchers investigate these often-overlooked aspects of biocrust ecology. We discuss both passive and active methods for sampling airborne organisms, highlighting their potential in studies of biocrust organisms. We present traditional techniques, such as microscope glass slides coated with adhesive substances, as well as more advanced equipment like Rotorods. For organism identification, we explore traditional morphological methods, but also introduce more modern approaches, such as metabarcoding, which allow for the simultaneous study of multiple organism groups. This review underscores the potential of these methods to enhance our understanding of the aerobiology of biocrusts. By shedding light on these dispersal dynamics, this review aims to support future research and foster advancements in biogeography, ecosystem restoration, and conservation strategies.

STINGLEES BEES AND URBAN SPACES: AN INVESTIGATION OF THE CONDITIONS FOR ADAPTATION TO CITY BUILDINGS AND LANDSCAPING

Stingless native bees are essential for the preservation of ecosystems as they contribute to the maintenance of biodiversity and the stability of forest fragments. Information on how these species behave in urban environments is still scarce in Brazil. For this reason, the aim of this study was to investigate the occurrence of stingless bees in the urban area of the city of Realeza (PR) through the localization of nests and active and passive capture methods. Sampling was conducted between October and December 2022, a period of peak nectar-producing species flowering in the region. The searches were carried out in five sectors, covering both public and private areas, and aspects of the landscape such as floral species, physical characteristics of buildings, and nesting substrates were recorded. During the survey, 23 nests of Tetragonisca angustula and Scaptotrigona depilis were recorded, and foraging activities of Scaptotrigona bipunctata and Plebeia spp. were also detected. The urban forest fragments of Realeza face challenges for stingless bees due to urbanization and exotic vegetation. Tetragonisca angustula adapts to artificial substrates, while Scaptotrigona depilis depends on natural cavities. Wooden houses favor nesting, and strategies such as artificial shelters, native plants, and sustainable cultural practices are essential for conserving pollinators and ecosystem services.

Thermal Image Classification of Autistic Children Using Res-Net Architecture

The thermal Image Classification Method has been widely used for significant applications in many fields, including thermal images of the face. This study presents a method for thermal facial classification in children with autism spectrum disorder (ASD). Children with ASD have a neurological disorder that affects communication skills essential in daily life and often causes difficulties in social situations. As we know, the diagnosis of ASD currently still relies on human methods and does not yet have definite biological markers. Early diagnosis of ASD has a significant positive impact, especially in children. Deep learning techniques, especially in facial medical image analysis, have become a new research focus in ASD detection. Initial screening using a Convolutional Neural Network (CNN) model with a transfer learning approach offers great potential for early diagnosis of ASD. The use of thermal imaging as a passive method to analyze ASD-related physiological signals has been proposed. In previous research, a deep learning model was developed to classify the faces of autistic children using thermal images. Therefore, this study aims to create a new Thermal Image Classification model for Autistic Children Using Res-Net Architecture. The architectures applied are ResNet-18, ResNet-34, and ResNet-50. As a comparison system, several of the same parameter values are used: epoch 100, batch size 2, SGD, Cross-entropy, learning rate 0.001, and momentum 0.9. The study test results show that the results of ResNet-18 are 97.22%, ResNet-34 99.22%, and ResNet-50 99.41%. Based on these results, ResNet-50 has the highest value.

Multi-Temporal Image Fusion-Based Shallow-Water Bathymetry Inversion Method Using Active and Passive Satellite Remote Sensing Data

In the active–passive fusion-based bathymetry inversion method using single-temporal images, image data often suffer from errors due to inadequate atmospheric correction and interference from neighboring land and water pixels. This results in the generation of noise, making high-quality data difficult to obtain. To address this problem, this paper introduces a multi-temporal image fusion method. First, a median filter is applied to separate land and water pixels, eliminating the influence of adjacent land and water pixels. Next, multiple images captured at different times are fused to remove noise caused by water surface fluctuations and surface vessels. Finally, ICESat-2 laser altimeter data are fused with multi-temporal Sentinel-2 satellite data to construct a machine learning framework for coastal bathymetry. The bathymetric control points are extracted from ICESat-2 ATL03 products rather than from field measurements. A backpropagation (BP) neural network model is then used to incorporate the initial multispectral information of Sentinel-2 data at each bathymetric point and its surrounding area during the training process. Bathymetric maps of the study areas are generated based on the trained model. In the three study areas selected in the South China Sea (SCS), the validation is performed by comparing with the measurement data obtained using shipborne single-beam or multi-beam and airborne laser bathymetry systems. The root mean square errors (RMSEs) of the model using the band information after image fusion and median filter processing are better than 1.82 m, and the mean absolute errors (MAEs) are better than 1.63 m. The results show that the proposed method achieves good performance and can be applied for shallow-water terrain inversion.

Passivated Zn Powders as Metal Anode

AbstractImpacted by heavy corrosion and poor connections, zinc (Zn) powders have rarely been considered as the raw materials of Zn‐ion aqueous batteries (ZABs). Nonetheless, the ease of controlling loadings of Zn powders entitles ZABs to better capacity match between negative and positive electrodes. Here, a simple and rapid chemical solution passivation method is reported, which leads to a thin, dense, and conformal passivation layer on Zn powder surface. The passivation layer suppresses parasitic reactions of Zn powder anode, mitigates corrosions, and extends the calendar life. Mixing with well‐dispersed carbon nanotubes, the passivated Zn powder anode is able to cycle 100 h under 3 mA cm−2 and 3 mAh cm−2 at depth of discharge of 41.3%. Besides, the anode with negative/positive electrode capacity ratio of 5.95 improves the energy density of the Zn powder||MnO2 full cell to 70 Wh Kg−1. Such a simple “one‐step” passivation method is believed to be a “drop‐in” technique applied in the scalable manufacture of ZABs.

Study on the Dynamic Response of the Carbody–Anti-Bending Bars System

Ride comfort is an important requirement that passenger rail vehicles must meet. Carbody–anti-bending system is a relatively new passive method to enhance the ride comfort in passenger rail vehicles with long and light carbody. The resonance frequency of the first bending mode (FBM) of such vehicle is within the most sensitive frequency range that affects ride comfort. Anti-bending bars consist of two bars that are mounted under the longitudinal beams of the carbody chassis using vertical supports. When the carbody bends, the anti-bending bars develop moments in the neutral axis of the carbody opposing the bending of the carbody. In this way, the carbody structure becomes stiffer and the resonance frequency of the FBM can be increased beyond the upper limit of the discomfort range of frequency, improving the ride comfort. The theoretical principle of this method has been demonstrated employing a passenger rail vehicle model that includes the carbody as a free–free Euler–Bernoulli beam and the anti-bending bars as longitudinal springs jointed to the vertical supports. Also, the method feasibility has been verified in the past using an experimental scale demonstrator system. In this paper, a new model of the carbody–anti-bending bar system is proposed by including three-directional elastic elements (vertical and longitudinal direction and rotation in the vertical–longitudinal plane) to model the fastening of the anti-bending bars to the supports and the vertical motion of the anti-bending bars modelled as free–free Euler–Bernoulli beams connected to the elastic elements of the fastening. In the longitudinal direction, the anti-bending bars work as springs connected to the longitudinal elastic elements of the fastening. The modal analysis method is applied to point out the basic properties of the frequency response functions (FRFs) of the carbody–anti-bending bars system, considering the bounce and FBMs of both the carbody and the anti-bending bars. A parametric study of the FRF of the carbody shows that the vertical stiffness of the fastening should be sufficiently high enough to eliminate the influence of the modes of the anti-bending bars upon the carbody response and to reduce the anti-bending bars vibration in the frequency range of interest. Longitudinal stiffness of the elastic elements of the fastening is critical to increase the bending resonance frequency of the carbody out of the sensitive range. Longer anti-bending bars can improve the capability of the anti-bending bars to increase the bending resonance without the risk of interference effects caused by the bounce and bending modes of the anti-bending bars.

Ring-in-Ring Assembly Facilitates the Synthesis of a [12]Cycloparaphenylene ABC-Type [3]Catenane.

Cycloparaphenylenes (CPPs) represent a significant challenge for the synthesis of mechanically interlocked architectures, because they lack heteroatoms, which precludes traditional active and passive template methods. To circumvent this problem and explore the fundamental and functional properties of CPP rotaxanes and catenanes, researches have resorted to unusual non-covalent and even to labor-intensive covalent template approaches. Herein, we report a ring-in-ring non-covalent template strategy that makes use of the surprisingly strong non-covalent inclusion of crown ethers into suitably sized CPPs. By threading a secondary ammonium salt through the crown ether and closing the third ring via CuAAC click reaction, we obtained a rare ABC-type hetero-[3]catenane comprising [12]CPP, 24-crown-8 and a dibenzylammonium macrocycle. X-ray crystallography shed light on the ring-in-ring pre-organization and the [3]catenane topology was confirmed by NMR and MS-MS studies. Molecular simulations provided insights into the intriguing ring-vs.-ring-vs.-ring dynamics of the [3]catenane, which are highly dependent on the protonation state of the dibenzylammonium site. This ring-in-ring assembly strategy opens new avenues for the synthesis of complex CPP architectures and their use in functional supramolecular systems.

Analysis of antibody detection data of Mycoplasma pneumoniae in a hospital in Beijing City from 2017 to 2024

Objective: To explore the distribution characteristics of Mycoplasma pneumoniae (MP) antibody detection data in hospital, provide data reference for the prevention and control of MP infections. Methods: A single-center retrospective study was conducted on 20 639 patients with suspected Mycoplasma pneumoniae (MP) infection from March 2017 to February 2024 at the outpatient, emergency, and inpatient departments of Peking University Third Hospital. The age range was from 0 to 105 years, with 11 286 males and 9 353 females. The passive agglutination method was used to detect MP antibodies in patient serum, and SPSS 22.0 statistical software was used for statistical analysis. The χ2 test was used to analyze the differences in positive rates of MP antibodies among different genders, age groups, seasons, years, and antibody titers. The trend χ2 test was used to analyze the trend of detection rates with age changes. Results: Among the 20 639 patients, the positive rate of MP antibodies was 23.19%(4 786/20 639), with a higher positive rate in females was 27.16%(2 540/9 353) compared to males (19.90%, 2 246/11 286;χ²=151.191, P<0.01). The positive rate in children was 37.13%(2 731/7 356)significantly higher than in adults(15.47%, 2 055/13 283;χ²=1 246.433, P<0.01). The 6 to <12 year age group (63.11%, 1 223/1 938) had the highest positive rate of MP antibodies, followed by 12 to <18 year old group (56.78%, 385/678). The positive rate of MP antibodies increased with age from 0 to 12 years old but gradually decreased after 12 to <18 years old (χ2=3 848.393, P trend<0.01). The annual MP antibody positivity rates from 2017 to 2023 were 26.92%, 29.23%, 27.46%, 18.43%, 17.16%, 11.89%, and 23.72%, respectively, with statistically significant differences among the years (χ²=387.519, P<0.01). The MP antibody positive rate was high in autumn over the course of 7 years (χ²=242.560, P<0.01). The positive rates of MP antibodies for the years 2017-2019, 2020-2022, and 2023-2024 are (28.00%, 16.60%, 21.84%), respectively, with statistically significant differences among the three periods(χ²=295.845, P<0.01).The monthly positive rates of MP antibody in different years were (5.63% to 43.11%). In the MP antibody titer, qualitative testing was conducted on 4 563 patients and 16 076 patients had a semi-quantitative MP antibody titer of ≥1∶160 with a positive rate of 16.03%(2 577/16 076). Among the proportion of children with high titers of MP antibodies ≥1∶1 280 was 11.11%(798/7 182). Conclusion: The positive rates of MP antibodies in hospital in the Beijing area vary among different genders, ages, and seasons, with a higher incidence in autumn, mainly among children and adolescents.

Reusable EWOD-based microfluidic system for active droplet generation.

Droplets are essential in a wide range of microfluidic applications, but traditional passive droplet generation methods suffer from slow response speed and the need for precise flow rate adjustment. Here, we present an active droplet generation method through electrowetting-on-dielectric (EWOD). Electrowetting is a technique that uses an electric field to change the wettability of a surface. In our method, we apply an electric field to the laminar flow of the dispersed and continuous phases in a microchannel, which induces the discretization of the dispersed thread and leads to droplet formation. A key feature of the proposed active droplet-generating microfluidic device is the reusability of the EWOD actuation substrate, dramatically reducing operational costs. In addition, this approach offers significant advantages over passive methods, including fast response speeds, a wider range of droplet sizes, and greater control over droplet size. In addition, the ultrathin polymer film used in this device allows for a low electrowetting voltage, which helps to prevent damage to encapsulated cells. We believe that our active droplet generation method is a promising new method for generating droplets in microfluidic applications. It is faster, more versatile, and more precise than passive methods, making it ideal for a wide range of applications, including single-cell genomics and drug discovery.

Analytical computation of arm inductor for minimizing MMC circulating current using passive method

The study of circulating currents in modular multilevel converters is vital for improving their efficiency and reliability. The circulating current may arise from capacitor voltage unbalancing, modulation imperfections, load variations, and transient conditions. Such currents typically induce distortions in arm currents, exhibiting second-order harmonics that lead to power losses and negatively impact the ratings of converter components as well as the amplitudes of capacitor voltage ripples. Despite ongoing research, effective strategies to mitigate circulating currents are limited. This paper aims to systematically address this issue by selecting key design parameters specifically arm inductance and capacitor values, to suppress circulating currents. The methodology incorporates harmonic analysis and instantaneous power theory to derive expressions for arm inductance. Initial modelling includes common mode and differential mode analyses, leading to an examination of harmonic content. Analysis reveals that the selection of the arm inductor value is mainly influenced by the second-order harmonic component, whereas the capacitor value is determined by the fundamental harmonic component. By adopting this methodology, the boundary limit for arm inductor selection can be determined. This article proposes a novel expression for arm inductor selection. The proposed expression mainly depends on factors such as load, submodule capacitor voltages, submodule capacitor, and differential current. By selecting an appropriate inductor value based on converter-rated parameters, circulating current within the system can be effectively suppressed. The methodology offers a practical framework for arm inductor selection. Simulation results validation shows strong alignment with analytical results with the error margin of less than 1%, hereby the MMC parameter can be determined with better accuracy through analytic method.

Research on weakly conservative passive fault-tolerant control method considering the fault distribution

Research on weakly conservative passive fault-tolerant control method considering the fault distribution

Double-faced diffusive gradient in thin films sampler (df-DGT): Proposing an improved DGT sampler design for water deployments.

The Diffusive Gradients in Thin Films (DGT) technique has become the most widely used passive sampling method for inorganic compounds. This widespread adoption can be partly attributed to the development of new binding phases that facilitate the sampling of numerous analytes. In contrast, to date, the DGT sampler for inorganic compounds has not seen any significant design improvements. In this manuscript, a new design for the DGT sampler is proposed. The new design, referred to as the Double-Faced DGT (df-DGT) sampler, features dual sampling windows, enabling a twofold increase in analyte mass uptake compared to the conventional DGT sampler. The proposed sampler was characterized for Cd, Co, Mn, Ni, and Zn by performing the following tests: deployment curves, the effect of the diffusive boundary layer (DBL), pH, ionic strength and deployment in synthetic samplers. It was demonstrated that the df-DGT sampler can accumulate twice the mass over time compared to the conventional DGT sampler. The effects of the DBL, pH, and ionic strength on the measurements of Cd, Co, Mn, Ni, and Zn, when sampling with the df-DGT, were consistent with those previously reported for the conventional DGT sampler. When the df-DGT sampler and the DGT sampler were deployed simultaneously in synthetic samples with varying concentrations of Cd, Co, Mn, Ni, and Zn, no significant differences were observed (at the 95% confidence level) in the results obtained from both samplers. To the best of our knowledge, this is the first time a new DGT sampler, featuring conceptual innovations, is being proposed for sampling inorganic species in water. The proposed sampler is twice as effective in terms of mass uptake and is useful for short deployments or enhancing sensitivity. In the future, the application of this sampler could potentially be expanded to other uses, such as o-DGT.

Geometrical parameters effect on aerodynamic performance of infinite tubercle leading edge wings

ABSTRACT Micro aerial vehicles (MAVs) encounter aerodynamic challenges due to their small size and low flying speed, often experiencing stall at low angles of attack. This study aims to investigate the effects of sectional airfoil geometries, including thickness, maximum thickness location, and camber, on the aerodynamic performance of fixed-wing MAVs inspired by the passive control method observed in Humpback whales. The investigation employs 3D, unsteady, viscous, and turbulent simulations using the detached eddy simulation turbulence model to understand the physical phenomena. Results reveal that increasing the thickness of the infinite wing by approximately 9.5% results in a decrease of lift and drag coefficients by 19.8% and 12%, respectively. Furthermore, shifting the maximum thickness location from 18%c to 36%c enhances the lift-to-drag ratio (L/D) by nearly 16%. However, an increase in camber leads to a rise in drag coefficient. In conclusion, this research sheds light on the aerodynamic effects of sectional airfoil geometries on fixed-wing MAVs, particularly in pre-stall conditions. Understanding these effects contributes to the development of strategies for improving MAV maneuverability and aerodynamic performance.

Determination of optimum dose of using Cao (quick lime) for acid mine water management on pH parameters in settling pond 81W pt. Antareja Mahada Makmur Site Perkasa Inakakerta Bengalon district, East Kutai Regency, East Kalimantan

Background: Efforts to manage AAT can be done in several ways, namely by using active and passive methods. For active management is by adding certain chemicals such as lime or alum so that a reaction occurs to control pH and TSS levels. This is related to the actual problems of the research area due to the pH that does not meet the quality standards for coal mining wastewater. The low pH parameters in the research area are a problem in the mining environment, if the content of mining wastewater that has an acidic pH is not neutralized and then directly discharged into the river body causes environmental pollution such as, disruption of aquatic biota that cannot live with an acidic pH and also has an impact on river water which will later be used by the local community for daily activities. Method: The research methodology is divided into 3 stages, namely: pre-field stage, field stage, and studio or post-field stage. Titration testing on each water sample with quicklime Titration testing to determine the optimum dose using initial measurement data obtained from the field. The dose used starts from 0.1 gr/L to neutral pH according to Environmental Quality Standards. Dosage determination is carried out in the Laboratory owned by PT Antareja Mahada Makmur site Perkasa Inakakerta using a jar test tool. Furthermore, the first data analysis carried out was to analyze rainfall data. From the results of actual flow rate measurements carried out at the inlet of the sedimentation pond and pH measurements in each compartment, the process of determining the amount of efficient quicklime dose for water quality management in the sedimentation pond was carried out. Results: The initial pH test results averaged 3.86. After the titration test, the final pH averaged 7.45. The results of testing several dose ranges obtained for the initial pH of 3.86 were 0.05 gr/L. Why did the researchers only use one initial pH value because it was the average result of daily measurements carried out for 10 days. To change the optimum dose from a laboratory scale to a field scale is to multiply the optimum dose by the hourly discharge entering the settling pond 81W. Conclusion : Several efforts have been made by PT Antareja Mahada Makmur, one of which is stabilization using the lime addition method on coal mining wastewater.