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This study’s aim is to introduce a high-performance sorbent for the removal of both anionic (Congo red; CR) and cationic (methylene blue; MB) dyes from aqueous solutions.

Sodium silicate is adopted as a substrate for GO and AgNPs with positive charge are used as modifiers. The synthesized nanocomposite is characterized by FTIR, FESEM, EDS, BET and XRD techniques. Then, some of the most effective parameters on the removal of CR and MB dyes such as solution pH, sorbent dose, adsorption equilibrium time, primary dye concentration and salt effect are optimized using the spectrophotometry technique.

The authors successfully achieved notable maximum adsorption capacities (Qmax) of CR and MB, which were 41.15 and 37.04 mg g⁻¹, respectively. The required equilibrium times for maximum efficiency of the developed sorbent were 10 and 15 min for CR and MB dyes, respectively. Adsorption equilibrium data present a good correlation with Langmuir isotherm, with a correlation coefficient of R2 = 0.9924 for CR and R2 = 0.9904 for MB, and kinetic studies prove that the dye adsorption process follows pseudo second-order models (CR R2 = 0.9986 and MB R2 = 0.9967).

The results showed that the proposed mechanism for the function of the developed sorbent in dye adsorption was based on physical and multilayer adsorption for both dyes onto the active sites of non-homogeneous sorbent.

The as-prepared nano-adsorbent has a high ability to remove both cationic and anionic dyes; moreover, to the high efficiency of the adsorbent, it has been tried to make its synthesis steps as simple as possible using inexpensive and available materials.

This paper aims to control the clay’s dispersion within the PA6 matrix. Cloisite Na+, a naturally occurring sodium montmorillonite (NaMMT), and Cloisite 30B and 93A, two organophilic MMT (OMMT), were used for this purpose.

By using a twin-screw extruder for melt mixing, Polyamide 6 (PA6)/NaMMT nanocomposites with 1, 3, 5 and 10 Wt.% Cloisite Na+ and PA with 5 and 10 Wt.% Cloisite 30B and 93A were created. PA6/OMMT nanocomposite to investigate how organoclay disperses within the PA6.

The link among PA6 and the silicate layer was evaluated via (FTIR), confirming presence of a compact contact between the nanosilicate layer and PA6 segments. Thermal behavior of obtained nanocomposites was evaluated through a thermogravimetric analyzer. The data confirmed that the thermal behavior of PA6 was moderately improved once addition 5 Wt.% filler, in the order: Cloisite Na+>Cloisit 93A>Cloisit 30B.Electrical properties have been studied through measuring dielectric constant, dielectric loss and conductivity measurment that procced at frequencies from 10^–1 to 107 Hz and temperatures from 40°C to 120°C, dielectric constant (έ) and dielectric loss (έ) of the nanocomposite were sharply increased with increasing the two parameters temperature and frequency.

The hybrid nanomaterials of PA6/ Cloisite Na+, Cloisite 93A or Cloisite 30B can be credited as electronic nanodevices and microwave semiconductors materials with a small amount of nanoclay filler as illustrated in the conclusion.

Salt rock from salt lakes can serve as a cost-effective material for subgrade filling, as demonstrated in projects like the Qarhan Salt Lake section of the Qinghai-Tibet Railway and the Qarhan Salt Lake section of the G215 Highway. This state-of-the-art paper aims to summarize the engineering properties of salt rock filling and present the advances of its utilization.

This paper collects and analyzes laboratory and field data of salt rock filling from previous studies to present a comprehensive analysis of the engineering properties and utilization of salt rock fillings.

Salt rock primarily contains minerals such as halite and glauberite, which contribute to its unique phase-changing behavior under varying environmental conditions, impacting its mechanical properties. Salt rock filling shrinks when in contact with vapor or unsaturated brine and expands under cooling or evaporation. Its use is particularly recommended for arid regions, with specific restrictions depending on the structure type. This paper discusses suggested countermeasures to mitigate these issues, as well as key quality acceptance indices for salt rock filling compaction. Moisture content after air-drying is recommended as a crucial parameter for construction quality control.

This review aims to support future research and engineering practices in salt rock subgrade applications.

This study investigates whether horizon problems affect the allocation of capital budgets and their implementation in a government setting.

We use data from 2005 to 2020 for local governments in Indonesia, which apply a limit of two five-year terms for mayors. We use regression analyses for panel data with total observations of 4,541 local government years from 448 unique local governments. We also use graphical analyses and t-tests to provide robustness to our results.

Mayors allocated lower capital expenditures in the second term than in the first. Capital budget allocation is lower for local governments whose mayors are older than 60. Our additional analysis shows that incumbents seeking re-election allocate more capital expenditure than those not seeking re-election.

This study contributes to the literature on the behavioral effect of term limits on local government's allocation and implementation of capital budgets. Limiting elected government officials to a certain number of terms will prevent the monopoly of power. However, it may negatively affect budget allocation on capital programs in their last term. Our findings should interest public policymakers in discerning the costs and benefits of term limits for elected offices.

Most studies on horizon problems have focused on the corporate setting. This study provides evidence of the effects of horizon problems in the government setting, especially in Asia.

This research aims to investigate the disciplinary functions of depositors and subordinated debt holders within Indonesia's dual banking system, examining the impact of regulatory changes on market discipline.

The study employs a comprehensive analysis of the dual banking system in Indonesia over 15 years. Utilizing a non-public dataset from the Financial Services Authority and the Indonesia Deposit Insurance Corporation, the study employs propensity score matching and difference-in-differences analysis.

The findings reveal distinct patterns in the exercise of market discipline by depositors over different regulatory regimes. During the blanket guarantee regime (2002–2005), depositors lacked the incentive to monitor banks but resumed their disciplinary role under the limited guarantee regime (2005–2017). Islamic banks faced simultaneous market and regulatory discipline, with market discipline prevailing.

This study contributes to the literature by providing novel insights into the interplay between regulatory changes, market discipline and depositor behavior within Indonesia's dual banking system. The utilization of a comprehensive non-public dataset from regulatory authorities adds to the originality of the research.

This study examines the impact of CSR (corporate social responsibility) on stock price volatility of oil and gas firms and, then identifies the moderating role of tax avoidance.

To achieve the study's purposes, 330 observations are extracted from 30 oil and gas firms for the period between 2010 and 2020, and the estimation method of the Generalized Least Squares (GLS) is used. Actually, the CSR is proxied using the ESG (environmental, social, and governance) score, and the stock price volatility is measured by the degree of stock price variations over 12 months, according to the last 52 week's price.

The main findings indicate that CSR negatively impacts the stock price volatility. Nonetheless, this negative relationship is moderated positively by tax avoidance. This result is robust to the variation in the measure of volatility, namely the systematic risk.

This research is helpful for investors to manage their portfolio risk as this article highlights the importance of engaging in sustainable development to reduce financial risk. This study also helps regulators and policymakers, such as environmental agencies and tax authorities, to reassess their control with oil and gas firms and record them according to their CSR practices, because this article emphasizes that it is not fair to pay taxes and engage in CSR practices at the same time.

The impact of CSR on stock price volatility is widely treated for firms. Nevertheless, the mechanisms that may affect this relationship are still seldom discussed. This study attempts to examine the impact of tax avoidance on the CSR–stock price volatility relationship for the oil and gas industry.

This paper aims to identify the role female body shape plays in clothing size and fit, as well as its impact on comfort and safety.

Existing issues and complaints from female clothing consumers reported within the literature were explored. Documented experiences provided justification to demystify the notion made by manufactures who market clothing for the hourglass body.

Clothing manufacturers continue to underestimate the impact of the female body in clothing design and construction. Manufacturers market the unrealistic notion of the hourglass body which often leads to wrong sizing and ill-fit. This might be responsible for the continued dissatisfaction experienced by female clothing consumers with more severe consequences in functional clothing compared to everyday clothing. For functional clothing (e.g. firefighter protective clothing), the implication could be life threating.

This review provides another perspective on the implication of the female body clothing design and production depending on the end-use: everyday versus functional clothing. In this study, the impact of the female body on clothing design and construction are discussed.

This paper aims to provide a full introduction, new classification, comparison and investigation of the challenges as well as applications of layerless 3D printing, which is one of the industry 4.0 pioneers.

Given the significance and novelty of uniform 3D printing, more than 250 publications were collected and reviewed in an unbiased and clear manner.

As a result, the majority of uniform parts printed in polymer form are known up to this point. In a novel division for better researchers’ comprehension, uniform printing systems were classified into three categories: oxygen inhibition (OI), liquid lubrication (LL) and photon penetration (PP), and each was thoroughly investigated. Furthermore, these three approaches were evaluated in terms of printing speed, precision and accuracy, manufacturing scale and cost.

The parameters of each approach were compared independently, and then a practical comparison was conducted among these three approaches. Finally, a variety of technologies, opportunities, challenges and advantages of each significant method, as well as a future outlook for layerless rapid prototyping, are presented.

We examine the impact of corporate sustainability performance (CSP) on corporate cash holdings, focusing on the moderating impacts of industry’s concentration, financial constraints, and institutional environments.

The empirical analysis is conducted on a sample of 31 countries from 2002 to 2018. We use the pooled OLS regressions controlling for fixed effects. We further address endogeneity issues using an instrumental variable approach, the Difference-in-Differences regression based on an exogenous shock, and the propensity score matching.

We find that firms with superior CSP hold more cash. This result is valid after a series of tests for robustness and endogeneity issues, suggesting a causal effect of CSP on corporate cash holdings. In the cross section, the positive impact of CSP on cash holdings is more pronounced for firms operating in highly concentrated industries, but attenuated for firms with financial constraints and for those operating in countries with better institutional environments. We further show that CSP affects cash holdings through the channel of financial distress risk.

In making investment decisions, investors should not only examine corporate financial performance and sustainability profile, but also understand the related cash holding levels and financial distress costs. Corporate managers making decisions on levels of cash holdings should pay more attention to their sustainability behavior, especially for firms operating in concentrated industries and/or facing financial constraints. Governments and authorities can apply regulations to encourage firms to engage more in sustainable activities, as well as establish good institutional environments in the country.

Using a comprehensive international dataset, our paper contributes to two strands of literature: the economic impact of CSP and the driver of cash holdings. We further focus on the moderating role of industry concentration and firms’ financial constraints. Our international sample also allows us to exploit the effect of country-level informal institutions.

As lubricating oils are used, their performance deteriorates and they become contaminated. The purpose of this paper is to investigate the lubrication performance of reclaimed 5 W-30 a fully synthetic used engine oil (UEO) with wear tests after refining it from a solvent-based extraction method using solvent (1-PrOH) and adsorbent materials such as cement, celite and deep eutectic solvent (DES).

The treated oil mixtures were prepared by blending engine oils with various adsorbent materials at 5% (w/w) in organic 1-PrOH solvent at a UEO: solvent ratio of 1:2 (w/w). The measurement of kinematic viscosity, density, the total acid number (TAN) and elemental analysis of oil samples was done by the ASTM standards D445/D446, D4052, D974 and D6595, respectively. Adsorbents and treated oil samples characterized by SEM-EDX, FTIR and UV analysis, respectively. Meanwhile, lubricating performance in tribological applications was evaluated through the wear test device using a rotating steel alloy 1.2379 cylinder and a stationary 1.2738 pin under 20, 40 and 80 kg load conditions. Worn surface analysis was done with SEM and 2.5D images.

It was found that when using the combination of cement and celite as an adsorbent in the reclamation of used engine oil demonstrated better lubricant properties. The properties of used engine oil were improved in the manner of kinematic viscosity of 32.55 from 68.49 mm²/s, VI (Viscosity index) value of 154 from 130, TAN of 3.18 from 4.35 (mgKOH/g) and Fe content of 11 from 32 mg/L. The anti-wear properties of used engine oil improved by at least 32% when 5% cement and 5% celite adsorbent materials were used together.

The paper is based on findings from a fully synthetic 5 W-30 A5 multi-grade engine lubrication oil collected after driving approximately 12.000 km.

The results are significant, as they suggest practical regeneration of used engine oil is achievable. Additionally, blending fresh oil with reclaimed used engine oil in a 1:1 ratio reduced wear loss by over 10% compared to fresh oil.

Reusing used engine oils can reduce their environmental impact and bring economic benefits.

This study showed that the properties of UEO can be enhanced using the solvent extraction-adsorption method. Furthermore, the study provided valuable insights into the metal concentrations in engine oil samples and their impact on lubrication performance. The order of the number of the grooves quantity and the possibility of the observed scuffing region trend relative to the samples was UEO > 5W-30 fresh oil > Treated oil sample with the adsorbent cement and celite together.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0209/