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The purpose of this paper is to develop an empirical equation of SRB corrosion based on their metabolic species.

Solution containing SRB metabolic species was simulated using abiotic chemistry approach. Linear polarization technique was used to measure the corrosion rate of X52‐sample in simulated solution containing SRB metabolic products species. The curve obtained from LPR data was then fitted using multiple non‐linear regression method by Minitab 15^® software.

Statistical analysis shows that sulphide and sulphite have significant effect on the X52 corrosion rate.

Using abiotic chemistry approach, an empirical equation that considers SRB metabolic species has been developed. The equation could be used to predict carbon steel corrosion rate by SRB.

Bdellovibrio bacteriovorus is a gram-negative predatory bacterium which can potentially inhibit microbiologically influenced corrosion by preying on sulfate-reducing bacteria (SRB). However, no researches about the inhibition are reported according to the authors’ knowledge. The purpose of this paper was to investigate the Inhibition effect of B. bacteriovorus on the corrosion of X70 pipeline steel induced by SRB.

The effect of B. bacteriovorus on the growth of SRB was studied by measuring the optical density at 600 nm (OD600) and sulfate concentration in culture medium. X70 pipeline steel was used as the test material to investigate the anti-corrosion effect of B. bacteriovorus on SRB by conducting electrochemical analysis (including Tafel polarization curves and electrochemical impendence spectroscopy) and weight loss measurement.

B. bacteriovorus could inhibit the growth of SRB in culture medium by its predation on SRB, which led to decrease of OD600 value and increase of sulfate concentration. The results of electrochemical analysis indicated that B. bacteriovorus had positive inhibition efficiencies on SRB-induced corrosion of X70 pipeline steel. Moreover, corrosion rate of X70 pipeline steel was declined from 19.17 to 3.75 mg·dm-2·day-1 by the presence of B. bacteriovorus.

This is the first report about using B. bacteriovorus to inhibit the corrosion induced by SRB. Compared to other anti-corrosion methods, the microbial inhibition methods exhibit more considerable application value due to its low cost, high efficiency and non-pollution.

The purpose of this paper is to develop an equation for the synergistic corrosion of SRB and CO₂ based on the D-W model.

The bacterial types in the a and ß pipelines were studied by the most probable number method, and the corrosion morphology of L360 in pipeline water samples was studied by surface analysis. The corrosion rate of L360 was studied using the weight loss method. The gray correlation method was used to calculate the degree of correlation between the influencing factors of corrosion under the synergistic effect of CO₂ and SRB. The curve obtained from PIPESIM software and experiments data was then fitted using multiple non-linear regression method by MATLAB software.

The equation was used to predict the corrosion of the ß pipeline for verification, and it was found that seven out of ten excavation sites were within a 20% error range.

Using the gray correlation method, an equation that considers synergistic corrosion of SRB and CO₂ has been developed based on the D-W model. The equation could be used to predict the corrosion rate of shale gas gathering pipelines through SRB and CO₂ synergistic corrosion.

The purpose of this work was to study the corrosion behaviour of X52 steel in the presence of sulphite.

The study was conducted in abiotic solutions containing species typical of sulphate-reducing bacteria (SRB) metabolism. Electrochemical techniques, i.e. linear polarization resistance (LPR), potentiodynamic and electrochemical impedance spectroscopy (EIS), were used to observe the corrosion kinetics and mechanism of X52 steel in the solution containing sulphite. Field emission scanning electron microscope (FESEM) and X-ray photoelectron spectroscopy (XPS) were used to characterize the corrosion products.

LPR and EIS results showed that the addition of sulphite ions to the abiotic solutions increased the rate of X52 steel corrosion. The increase of corrosion rate was due to the increase in the cathodic reaction in the presence of sulphite. It was also observed that sulphite thinned the protective FeS film and caused corrosive species to adsorb on the surface, resulting in an increase in corrosion rate.

This paper discusses the effects of sulphite on the corrosion behaviour of X52 steel in abiotic solution containing species typically produced by the SRB-type metabolic process. Irrespective of the presence of sulphide, sulphite is produced by SRB during their metabolic process. However, as far as is known, no published papers are available that discuss the effect of the presence of sulphite as one of the metabolic products of SRB.

This study aims to shed light on the corrosion behavior of X80 steel when sulfate-reducing bacteria (SRB) and permeating hydrogen interact.

In this study, electrochemical tests were conducted between 25 and 55 °C, and the surface morphology of the specimen was observed using scanning electron microscopy and three-dimensional photos. The composition of the oxide film was characterized by X-ray photoelectron spectroscopy (XPS).

Under the condition of 6 MPa simulated natural gas (15% H₂), the content of S-containing compounds (FeS and FeSO₄) in the corrosion products on the surface of the specimen decreases from 60.8% to 54.4%. This finding indicates that hydrogen permeation inhibits the metabolic processes of SRB in this environment. By comparing the hydrogen-uncharged specimen, it was found that under the condition of 6 MPa simulated natural gas (15% H₂) hydrogen charging, the uniform corrosion on the X80 surface was weakened, and the protection of the oxide film on the specimen surface in this environment was better than that without hydrogen charging.

To the best of the authors’ knowledge, most of these existing studies have focused on the effect of hydrogen on the mechanical properties of materials and very little is known about corrosion behavior in the hydrogen environment. In this study, a self-designed small gas phase hydrogen charging device was used to study the X80 surface corrosion behavior in the environment of the H₂-doped natural gas pipeline.

This study aims to explore the distinctive dynamics of knowledge sharing, empowering leadership, psychological empowerment, innovative work behavior, and the moderating impact of kinship employee engagement in the creative industries of SMEs in Tana Toraja, Indonesia.

Using structural equation modeling, this research analyzes quantitative data collected from 512 employees in creative industry SMEs.

Knowledge sharing is not found to be associated with psychological empowerment but is positively related to innovative work behavior. Empowering leadership is positively associated with both psychological empowerment and innovative work behavior. Psychological empowerment mediates the relationships between knowledge sharing and innovative work behavior, as well as between empowering leadership and innovative work behavior. Finally, kinship employee engagement moderates the relationship between psychological empowerment and innovative work behavior.

The cross-sectional design restricts establishing causal relationships among variables, suggesting the need for longitudinal studies. Contextual factors specific to Tana Toraja, such as cultural nuances and economic conditions, may not have been fully explored, impacting the applicability of findings elsewhere. Future research could mitigate these limitations by using larger and more diverse samples, using mixed-methods approaches and conducting longitudinal studies to track changes over time.

The findings underscore the importance of nurturing empowering leadership and promoting a culture of knowledge sharing to cultivate innovative work behavior. Moreover, leveraging kinship relationships can optimize organizational effectiveness and employee engagement in culturally nuanced settings.

Strengthening these organizational practices not only enhances SME performance in creative industries but also fosters community cohesion and contributes positively to societal well-being.

This research uniquely explores the interplay of knowledge sharing, empowering leadership, psychological empowerment and the role of kinship employee engagement in enhancing innovative work behavior within SMEs in culturally distinct contexts like Tana Toraja’s creative industries.

Expansion of the consumption of renewable energy is a significant issue for reducing global warming, to cope with climate change and achieve sustainable development. This study aims to examine how research and development expenditure (R&D) affects renewable energy development in developed G-7 countries over the period from 2000 to 2019. Variables of trade liberalization and CO₂ emissions are considered control variables.

This study has adopted a panel quantile regression. The impact of the variables on renewable development has been examined in quantiles of 0.1, 0.25, 0.5, 0.75 and 0.9. Also, a robust examination is accomplished by applying generalized quantile regression (GQR).

The empirical findings reveal a positive and significant relationship between R&D and the consumption of renewable energy in 0.1, 0.25, 0.5 and 0.75 quantiles. Also, the findings describe that the expansion of trade liberalization and CO₂ emissions can significantly increase the development of renewable energy in G-7 countries. Furthermore, GQR verifies the main outcomes.

These results have very momentous policy consequences for the governments of G-7 countries. Therefore, investment and support for the R&D section to promote the development of renewable energy are recommended.

This paper, in comparison to other research, used panel quantile regression to investigate the impact of factors affecting renewable energy consumption. Also, to the best of the authors’ knowledge, no study has perused the effect of R&D along with trade liberalization and carbon emissions on renewable energy consumption in G-7 countries. Also, in this paper, as a robustness check for panel quantile regression, the GQR has been used.

The purpose of this paper was to study some effective evaluation methods for the biocide performance on sulfate-reducing bacteria (SRB) biofilm.

The most probable number method, electrochemical impedance spectroscopy (EIS) measurements, scanning electron microscopy (SEM), three-dimensional (3D) photos and epifluorescent microscopy were used in this study.

The results showed that the minimum inhibitory concentrations and minimum bactericidal concentrations of them to sessile SRB were greatly more than planktonic SRB. The EIS of the two biocides indicated that the biofilm exposed to higher concentrations of biocide were much more compact and flat, which perfectly coincided with the SEM, 3D photos and the epifluorescent microscopies.

In this paper, it, thus, appears that these methods evaluating biocide performance on the SRB biofilm were really effective by comparing the performance of bis-quaternary ammonium salt (BAQS) and tetrakis hydroxymethyl phosphonium sulfate.