Scaling Tendency Research Articles

Investigation of Scaling and Materials' Performance in Simulated Geothermal Brine.

Geothermal energy generation faces challenges in efficiency, partly due to restrictions on reinjection temperatures caused by scaling issues. Therefore, developing strategies to prevent scaling is critical. This study aims to simulate the scaling tendencies and corrosion effects of geothermal fluids on various construction materials used in scaling reactor/retention tank systems. A range of materials, including carbon steel, austenitic stainless steel, duplex stainless steel, two proprietary two-part epoxy coatings, and thermally sprayed aluminium (TSA), were tested in a simulated geothermal brine. Experiments were conducted in a laboratory vessel designed to replicate the wall shear stress conditions expected in a scaling reactor. The tests revealed varying scaling tendencies among the materials, with minimal corrosion observed. The dominant scale formed was calcium carbonate, consistent with geochemical modelling. The findings suggest that despite the high operating temperatures, the risk of corrosion remains low due to the brine's low chloride content, while the wettability of materials after immersion may serve as a useful indicator for selecting those that promote scaling.

Investigation of pregnancy tendency, reproductive characteristics, and disability in women with multiple sclerosis: A secondary data analysis of the national registry in Iran

Abstract Background: Multiple sclerosis (MS) predominantly affects women of childbearing age, significantly impacting their quality of life (QOL).The diagnosis of MS can influence pregnancy intention, and the level of disability associated with MS may change before and after pregnancy. This study aims to analyze the reproductive characteristics of Iranian female patients with MS (PwMS) and their association with the Expanded Disability Status Scale (EDSS) and pregnancy tendency, providing valuable insights into disease progression and the development of tailored treatments. Methods: A cross-sectional study was conducted using data from the nationwide MS registry of Iran (NMSRI) from 2018 to 2021. Patients without a documented history of pregnancy, MS type, or EDSS score were excluded from the study. Various statistical methods, including nonparametric tests, the generalized estimating equation (GEE) model, and multiple logistic regression, were employed to analyze the data. Results: The study included 1120 PwMS with a median diagnostic age of 31 and a disease duration of 6 years. The majority had relapsing-remitting MS (RRMS) and the mean EDSS score at bassline was 1.5 ± 1.4. A history of pregnancy or abortion was associated with higher EDSS scores. Multiparity before MS diagnosis was linked to EDSS score ≥ 5, while this EDSS range was associated with decreased parity after MS diagnosis (all P-values < 0.05). Conclusion: Pregnancy and parity can affect the disability in female PwMS irrespective of clinical symptoms, diagnosis age, and MS type. Moreover, the chance of parity may be affected by a higher disability score, which should be considered in the clinical setting.

Mechanistic Insights into Micelle-Enhanced Nanofiltration for Heavy Metal Removal: Transformation of Ion Transport and Fouling Phenomena.

Toxic heavy metals are widely present in typical scenarios, such as mines and electroplating wastewater, presenting significant risks to biological and environmental safety. Membrane processes encounter a challenge in effectively intercepting heavy metals due to their small hydration radius. This research showcases the high efficiency of micelle-enhanced nanofiltration (MENF) in removing heavy metals. At the critical micelle concentration, sodium dodecyl sulfate demonstrated a high removal of Cu2+, Ni2+, Zn2+, and Cd2+ while maintaining substantial potential for complexation of heavy metals. The formation of micelles and the bonding of heavy metals with surfactants bolstered the resistance of heavy metal ions to transmembrane transport. The presence of heavy metals in ionic form in wastewater facilitated their complexation with surfactants or micelles. Notably, the valence state and concentration of interfering ions in the environment could slightly influence the removal of heavy metals by MENF. Additionally, MENF displayed remarkable antifouling properties. The loose gel layer created by surfactant molecules and the micelle enhanced the membrane permeability and reduced the scaling tendency of heavy metals. This study contributes to an improved understanding of the mechanisms involved in heavy metal rejection by using MENF.

Modeling Framework for Cost Optimization of Process-Scale Desalination Systems with Mineral Scaling and Precipitation.

Cost-optimization models are powerful tools for evaluating emerging water treatment processes. However, to date, optimization models do not incorporate detailed chemical reaction phenomena, limiting the assessment of pretreatment and mineral scaling. Moreover, novel approaches for high-salinity and high-recovery desalination are typically proposed without direct quantification of pretreatment needs or mineral scaling. This work addresses a critical gap in the literature by presenting a modeling framework that includes complex water chemistry predictions with process-scale optimization. We use this approach to conduct a technoeconomic assessment on a conceptual high-recovery treatment train that includes chemical pretreatment (i.e., soda ash softening and recarbonation) and membrane-based desalination (i.e., standard and high-pressure reverse osmosis). We demonstrate how to develop and integrate accurate multidimensional surrogate models for predicting precipitation, pH, and mineral scaling tendencies. Our findings show that cost-optimal results balance the costs of pretreatment with reverse osmosis system design. Optimizing across a range of water recoveries (i.e., 50-90%) reveals multiple cost-optimal schemas that vary the chemical dosing in pretreatment and the design and operation of reverse osmosis. Our results reveal that pretreatment costs can be more than double the cost of the primary desalination process at high recoveries due to the extensive pretreatment required to control scaling. This work emphasizes the importance of and provides a framework for including chemistry and mineral scaling predictions in the evaluation of emerging technologies in high-recovery desalination.

Safety of female ride-hailing passengers: Perception and prevention

Ride-hailing, as part of wider transitions to smart city, has emerged as a beneficial complement to urban public transport. However, the frequent occurrence of ride-hailing safety accidents in multiple countries has raised concerns about passenger safety on an international scale. Within this context, this study aims to investigate female passengers’ safety perception and prevention action when using ride-hailing services, helping establish better management and protection mechanisms for passenger safety. Using objective data from 7898 ride-hailing criminal adjudications (674 passenger victimizations) and subjective data from 596 Chinese female respondents, the safety perception scale and prevention tendency scale, with six potential variables, are developed to further examine the heterogeneity of perception and prevention. Results reveal that driver’s words and actions directly influence female passengers’ safety judgments regarding ride-hailing services and that traveling with companions significantly enhances their perceived safety. The main preventative actions identified include relying on mobile phones for information and communication, as well as avoiding risky ride-hailing situations. Furthermore, the analysis of individual heterogeneity has uncovered perception and prevention differences based on factors such as age, education level, residence conditions, ride-hailing frequency, and victimization experiences. These differences are evident in perception biases towards driver attitudes and accompanying travel, as well as variations in risk avoidance behaviors. The insights inductively derived hold fundamental conceptual and empirical value for scholarship on safety evaluation and crime prevention in the context of shared mobility. Additionally, the countermeasures proposed in this study can serve as a theoretical reference for enhancing the safety supervision of ride-hailing services, contributing to the establishment of safer, more reliable and more sustainable shared travel environment.

A study evaluating the relationship between phubbing levels and empathic attitudes of college students

The objective of this research is to investigate the relationship between phubbing levels and the empathy attitude of college students. In our descriptive and correlational study, data were gathered from 528 college students studying in the undergraduate program of a university in Eastern Türkiye. Personal information form, Phubbing Scale, and Empathic Tendency Scale were employed as data collection forms. The research’s findings were examined using the SPSS 22.00 package program, and all analyses were judged significant if the p-value is less than 0,05 (p<0.05). The average total scores of the college students were found to be 42.77±19.09 on the Generic Scale of Phubbing (GSP) and 62.52±7.56 on the Empathic Tendency Scale (ETS). We found a significant difference between the mean phubbing and empathic tendency scores of college students and the number of book readings per week, the number of friends, and the meeting with friends weekly. The conclusion was that there was a strong negative and significant association between students’ total mean scores on the ETS and GSP scales (r=-0.581, p=0.00).

Assessment of Groundwater Stability Using Corrosion and Scaling Tendency Indices on Selected Springs in the Manga Region in Nyamira County, Kenya

Assessment of Groundwater Stability Using Corrosion and Scaling Tendency Indices on Selected Springs in the Manga Region in Nyamira County, Kenya

Optimizing water hardness removal through electrodialysis: A comprehensive exploration using Box-Behnken design analysis

Water hardness significantly impacts water quality, influencing both industrial processes and daily domestic applications. This study investigates the efficacy of electrodialysis (ED) in removing hardness, aiming for a balanced approach that avoids aggressive or scaling tendencies. Response surface methodology (RSM) was employed to determine the interaction between the inputs and the hardness removal, optimizing key parameters using the Box-Behnken design (BBD). The resulting regression model, validated through analysis of variance (ANOVA), demonstrated a high R2 value of 0.9761 and an adjusted R2 value of 0.9454, indicating a robust fitness for hardness removal prediction. The interaction of both voltage and initial concentration holds significance in our investigative study. A notable hardness removal efficiency of 87% was achieved at a demineralization time of 47 min, an applied voltage of 11V and an initial concentration of 5.3 mmol/L. This research enhances our understanding of critical operating parameters in ED, offering insights for optimizing the process toward effective water softening and long-term water treatment.

Investigating Effects of Reverse Osmosis-Treated Water on the Corrosion Rate of Chains in Armoured Face Conveyor for Longwall Mining

Premature failure of armoured face conveyor (AFC) chains due to corrosion is a significant proportion of the unplanned downtime experienced on longwall equipment. The AFC chains are constantly in contact with water and wet coal. The premature failure issue of AFC chains has become more prominent since the introduction of longwall top-coal caving with its additional AFC. Reverse osmosis (RO) is a popular water treatment method for reducing salinity and dissolved solids, but its impact on the corrosion of the AFC chains is unclear. This study has been commissioned to investigate the direct effects of RO water on the corrosion of AFC chains. An immersion test was carried out using AFC chain steel submerged in two water samples: untreated dam water and treated water from an RO treatment plant. Elemental analysis was conducted for both water samples, and four corrosion indices were measured for both water samples. The RO water more vigorously dissolves calcium carbonate scales leading to increased corrosion of the AFC chains although the dam water has much higher levels of calcium, chloride, sulphate, sodium, and magnesium. Bicarbonate ions are the main alkaline factor of water that provides the buffering capacity to acids. Decreased alkalinity without balancing other ions in water causes high corrosivity and decreased scaling tendencies.

Investigation of differences in xenophobia, prosociality level, and sociodemographic characteristics in nursing students.

This study aimed to examine differences in xenophobia, prosocial behavior tendency, and sociodemographic characteristics among nursing students. The participants were 227 nursing students (29.1% male, 70.9% female) attending the nursing department in the spring semester of the 2019-2020 academic year. We used a personal identification form, xenophobia scale, and prosocial behavior tendency scale to collect the data. Among the participants, 24.7% were in first year, 30.4% were in second year, 21.6% were in third year, and 23.3% were in fourth year. Female students had higher prosocial behavior disposition, altruistic, and submissive scores than their male counterparts. The second-year students' prosocial behavior scores were higher than those of the third-year students. The male students' hatred, humiliation, and xenophobia scores were higher than those of the female students. The xenophobia scores were higher in those with two living parents and lower in those whose mothers had secondary education. We used the Kolmogorov-Smirnov test, Shapiro-Wilk test, and graphical assessments to test the quantitative data's compliance with normal distribution. We also employed the Student's t-test and one-way analysis of variance for data showing a normal distribution and Mann-Whitney U and Kruskal-Wallis tests for data showing non-normal distribution. To evaluate the relationships among variables, we used the Pearson correlation analysis for normally distributed variables and Spearman's correlation analysis for non-normally distributed variables. Women's prosocial behavior tendency total score was higher than men's, and men's xenophobia total score was higher than women's. There was a weak negative correlation between the positive behavior tendency and xenophobia total scores.

Electrolysis-induced hardness variation for quantitatively assessing the scaling tendency of circulating water

Abstract The scaling problem exists universally in circulating water systems. Efficient and accurate assessment of scaling tendency is a prerequisite for solving the problem. In this work, it proposes electrolysis to induce hardness variation, which connects with the water stability evaluation index for quantitatively assessing the scaling tendency of water. The quantitative assessment is further realized on the basis of qualitative assessment. Then, the dynamic simulation experiments of circulating water are carried out to provide support for the electrolysis-induced hardness variation which clarifies the criteria that can meet the actual water requirements. This work can achieve an efficient and accurate quantitative assessment of the scaling tendency, which is of great significance for solving the scaling problem of circulating water systems.

Developing a phenomenological model to simulate single and mixed scale formation during flow in porous media: Coupling a salt precipitation model with an ion transport equation under dynamic conditions

Water flooding and pressure maintenance are recommended to improve oil recovery practices after low recovery of petroleum reservoirs occurs during primary production. Salt crystal formation is a frequent occurrence when using these techniques. Several experimental, numerical, and theoretical studies have been done on the mechanisms underlying scaling and permeability reduction in porous media; however, there has not been a satisfactory model developed. This study developed a phenomenological model to predict formation damage caused by salt deposition. Compared with existing models, which provide a scaling tendency, the proposed model predicts the profile of scale deposition. The salt precipitation model simulates reactive fluid flow through porous media. A thermodynamic, kinetic, and flow hydrodynamic model was developed and coupled with the ion transport equation to describe the movement of ions. Further, a set of carefully designed dynamic experiments were conducted and the data were compared with the model predictions. Model forecasts and experimental data were observed to have an average absolute error (AAE) ranging from 0.68% to 5.94%, which indicates the model's suitability.

Integrated analysis approach of water and solids for root cause of injectivity decline of water injection well – A case study

Accurate sampling and analysis of injection and flow back water and solids are pivotal to identify the root causes of injectivity decline of water injection well. The present paper is focussed on case study of detailed characterization of injection and flowback water and solids using combination of techniques such as X-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy, inductively coupled plasma optical emission spectroscopy, ion chromatography and water isotope analyser in investigating the cause of injectivity decline. The present study emphasizes the effect of pressurized and non-pressurized water sampling on water analysis results, their scaling tendencies and correlation with compositions of solids encountered. Surface pressurized injection water sample pH result was found acidic with a higher dissolved iron and lower total suspended solids (TSS). Non-pressurized water samples showed comparatively higher pH due to release of CO2. Langelier saturation index (LSI) and ScaleSoftPitzer™ program SI of pressurized water sample showed lower scaling tendency than the non-pressurized water sample. Non-pressurized water samples contained significantly higher concentrations of TSS than the pressurized water sample indicated precipitation of salts in non-pressurized sample. Composition of TSS revealed presence of iron-based compounds, calcite and gypsum. Geochemical and water isotope analysis showed identical composition of injection and flowback water. XRD and XRF analysis of trapped solids revealed different forms of iron oxides and iron sulphides as major phase along with appreciable amount of calcite and quartz. XRF analysis also showed traces of Cr, Mo, and Ni in trapped solids indicated corrosion of tubing/pipes. Solid composition correlates with scaling tendency predicted by ScaleSoftPitzer™ program SI. Presence of iron in pressurized injection water and iron compounds in solids indicate iron-based scale/corrosion as key reason for reduction in injectivity of the well. Systematic sampling, accurate and integrated analysis of water and solids can help to find the dominant causes of injectivity decline and direct oilfield engineers at well site to take appropriate remedial and preventive action.

A comparative parametric investigation of thin diamond-like and polymer-like carbon coatings to explore carbonate anti-scaling performance

Five coatings, among diamond-like carbon (DLC), polymer-like carbon (PLC), and a polymer composite (PPS-based) were applied to a corrosion-resistant alloy substrate and characterized to determine major material parameters that influence carbonate scale deposition. A comparative parametric investigation was carried out using information on microstructures, mechanical properties, tribological characteristics, surface roughness, surface energy (hydrophobicity), and chemical properties. Both uncoated (bare metal) and coated substrates were repeatedly tested under static and hydrodynamic scaling conditions and analyzed for their scaling tendency, specifically mass gains, crystal morphology, adhesion strength. All selected coatings were confirmed to reduce scale deposition compared to the uncoated metal surfaces. The morphology and size of the calcium carbonate crystals (calcite) were primarily influenced by both the coating surface energy and the scaling conditions. The results also revealed a significant correlation between the coefficient of friction of DLCs and the scale deposition tendency, especially in hydrodynamic conditions. While the polymer composite coating outperformed other coatings due to its smallest scaling tendency, the DLC coatings offered a plurality of technical advantages, with several DLC coating parameters newly identified to predominantly influence carbonate scaling.

An Empirical Analysis of the Influencing Factor of International Reserve

International reserve refers to the assets that a country 's monetary authority can use to intervene in the foreign exchange market and pay the balance of payments at any time. With the development of China 's foreign economy, China 's foreign exchange reserves have grown rapidly since 1995, reaching a peak of $ 3.84 trillion in 2014.For a long time, international reserves have become one of the important academic topics actively studied and discussed by many economists at home and abroad. The purpose of this paper is to study the impact of various macroeconomic indicators on the scale of international reserves, in order to find out the most significant indicators that affect the scale of international reserves, and to provide a theoretical basis for optimizing international reserve management. By using Eviews to conduct a regression analysis on the data of the China statistic yearbook from 1981 to 2021, this paper attempts to find out the factor that influences the international reserve and put forward advice for improving international reserve management. According to the investigation of international reserves, economic scale, average import tendency and exchange rate, the final conclusion is that the impact of economic scale and average import tendency on the scale of international reserves is significant.

Reduced-Order Models Blend Chemistry, Machine Learning for Water-Property Analysis

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 213869, “Water Digital Avatar—Where Chemistry Is Mixed With Machine Learning,” by Jesse Farrell, SPE, and Sergey Makarychev-Mikhailov, SPE, SLB. The paper has not been peer reviewed. _ Water affects almost every operation in the exploration and production industry. Until now, time-intensive laboratory tests or cumbersome third-party simulators were required to extract physicochemical properties. In the complete paper, a family of machine-learning-based reduced-order models (ROMs) trained on rigorous first-principle thermodynamic simulation results is presented. The developed ROMs that predict water properties enable automated decision-making and improve water-management work flows. The presented approach can be extended to other oilfield, chemical, and chemical-engineering applications. Introduction The properties of the water phase and all produced fluids directly influence flow assurance, three-phase flow pressure/volume/temperature modeling, and fluid-compatibility aspects across the full life cycle of the well, including during well construction, stimulation, and production operations. Modeling these systems enables one to predict, mitigate, and, in some cases, completely prevent deleterious effects in tubing, the reservoir, and near-wellbore regions. First-principle thermodynamic simulations are often considered to be ground truth in the oilfield industry and are widely used in place of time-consuming laboratory experiments. The use of rigorous thermodynamic software, however, is not always practical. In certain cases, commercial and open-source simulators are overloaded with functionality unnecessary for a task, require training of personnel, and are often difficult to incorporate into digital work flows in the cloud or to deploy at the edge on surface equipment or the downhole tools available to model changing conditions in real time. This is where ROMs find their application because they are fast, reasonably accurate, and highly customizable solutions. The authors’ scientific hypothesis was that machine-learning-based ROMs can be used to quantify the physicochemical properties and scaling tendencies of oilfield waters in place of rigorous, first-principle thermodynamic models. Methods The United States Geological Survey (USGS) Produced Waters Geochemical Database was used as the initial data source for this study. The original database contains approximately 115,000 produced-water and other deep-formation water samples collected and characterized in the United States in the past 120 years. Although the USGS database is an excellent source, the data still required cleaning and enrichment. For the first step, inconsistent, poorly populated, and outlier samples were removed, which led to noticeable data attrition and resulted in approximately 85,000 “clean” records. The enrichment phase included several manipulations and alterations of the original data. The resulting data set is not always accurate regarding individual samples but is much better populated than the original one in terms of minor ion concentrations, and is believed to be representative on a large scale.

Empathy as Mediator in Relationship between Self-Compassion and Prosocial Behavior among Adolescents

As a construct which promotes having compassion for ourselves, self-compassion has been found to have an inconsistent relationship with prosocial behaviour. However, the relationship between self-compassion and prosocial behaviour might be mediated by another predictor, such as empathy. The lack of literature discussing self-compassion in adolescents also encouraged this research. In this study, we examine the mechanism between self-compassion and prosocial behaviour through empathy as a possible mediating factor. Participants of this study were 303 adolescents in Indonesia aged 11-18 years old who filled out Self-Compassion Scale, Basic Empathy Scale and Prosocial Tendencies Measure-Revised. All the data were analyzed using the mediation analysis using approach introduced by Hayes. The results of statistical analysis showed there was a direct significant effect of self-compassionon prosocial behaviour (c = 0.10, p<0.05), and there was no significant effect from self-compassionon empathy (b=0.04, 95% CI [-0.030, 0.101]). Therefore, there was no indirect effect from self-compassionto prosocial behaviour through empathy. It can be concluded that empathy is not a mediator in the relationship between self-compassion and prosocial behaviour in adolescents.

Optimization of salinity and composition of injected low salinity water into sandstone reservoirs with minimum scale deposition

In this study, a mechanistic and comprehensive examination of the impact of the scale formation situation of different diluted seawater levels was conducted to investigate the influence of important factors on the performance and efficiency of low salinity water. To clarify the effective participating mechanisms, scale precipitation by compatibility test, field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDX) analysis, zeta potentials as surface charge, ion concentration changes, contact angle, pH, CO2 concentration, electrical conductivity, and ionic strength were analyzed. The results showed that increasing the dilution time to the optimal level (10 times-diluted seawater (SW#10D)) could effectively reduce the amount of severe precipitation of calcium carbonate (CaCO3) and calcium sulfate (CaSO4) scales. However, the reduction in CaCO3 scale precipitation (due to mixing different time diluted seawater with formation brine) and its effect on the wettability alteration (due to the change in surface charge of OLSW/oil and sandstone/OLSW) had higher impacts. The zeta potential results have shown that OLSW with optimum salinity, dilution, and ionic composition compared to different low salinity water compositions could change the surface charge of OLSW/oil/rock (− 16.7 mV) and OLSW/rock (− 10.5 mV) interfaces toward an extra negatively charged. FESEM and contact angle findings confirmed zeta potential results, i.e. OLSW was able to make sandstone surface more negative with diluting seawater and wettability changes from oil-wet toward water-wet. As a result, SW#10D was characterized by minimum scaling tendency and scale deposition (60 mg/l), maximum surface charge of OLSW/oil/rock (− 16.7 mV), and the potential of incremental oil recovery due to wettability alteration toward more water-wetness (the oil/rock contact angle ~ 50.13°) compared with other diluted seawater levels.

Research on time series forecasting method of ion concentration in produced fluid

AbstractIn the research on strong alkali‐surfactant‐polymer flooding scaling prediction, the variation characteristics of ion concentration in the produced fluid are obviously consistent with those of scale component content. Consequently, studying the variation tendency of ion concentration in produced fluid is helpful for further revealing the scaling tendency. Given the periodicity and chaos characteristics of the ion concentration data of the produced fluid, an echo state network (ESN) is used to realize the relevant time series forecasting. Simultaneously, to cope with the failure of the ESN in selecting suitable reservoir parameters according to different characteristics of time series, a modified discrete particle swarm optimization algorithm based on objective space decomposition is used to optimize the reservoir parameters. The experimental results indicate that the improved ESN presents the lowest error and is the closest to the target value.

Apakah Romantic Breakup Berperan terhadap Perilaku Impulsive Buying? : Studi Korelasional pada Mahasiswa

This study aims to identify the relationship and role of romantic breakups on impulsive buying in college students. This study used a non-experimental correlational method with a quantitative approach through regression and descriptive statistical analysis. The sampling technique used in this study was non-probability sampling with a saturation sampling method. The subjects consisted of 62 students of the Faculty of Psychology at a University in Bandung who had experienced a romantic breakup. Data was collected through an online questionnaire containing the Breakup Distress Scale (BDS) and Impulse Buying Tendency Scale (IBTS) measuring instruments using the help of Google Forms. Data analysis techniques used Pearson's Correlation test and regression test. The results of this research showed that there was no significant role of distress due to a romantic breakup in impulsive buying (r2 = 0.004; p = 0.605).