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In this study, the oxidative degradation performance of indigo wastewater based on electrochemical systems was explored. The decolourization degrees, removal rate of chemical oxygen demand and biochemical oxygen demand of the indigo wastewater after degradation were evaluated and optimized treatment conditions being obtained.

The single factor method was first used to select the electrolyte system and electrode materials. Then the response surface analysis based on Box–Behnken Design was chosen to determine the influence of four independent variables such as FeCl₃ concentration, NaCl concentration, decolourization time and voltage on the degradation efficiency.

On the basis of single factor experiment, the electrode material of stainless steel was selected in the double cell, and the indigo wastewater was electrolyzed with FeCl₃ and NaCl electrolytes. The process conditions of electrochemical degradation of indigo wastewater were optimized by response surface analysis: the concentration of FeCl₃ and NaCl was of 16 and 9 g/L, respectively, with a decolourization time of 50 min, voltage of 10 V and decolourization percentage of 98.94. The maximum removal rate of chemical oxygen demand reached 75.46 per cent. The highest ratio of B/C was 3.77, which was considered to be more biodegradable.

Dyeing wastewater is bringing out more and more pollution problems to the environment. However, there are some shortcomings in traditional technologies such as adsorption and filtration. As a kind of efficient and clean water treatment technology, electrochemical oxidation has been applied to the treatments of various types of wastewater. The decolourization and degradation of indigo wastewater is taken as an example to provide reference for the treatment of wastewater in actual plants.

The developed method provided a simple and practical solution for efficiently degrading indigo wastewater.

The method for the electrochemical oxidation technology was novel and could find numerous applications in the degradation of printing and dyeing wastewater.

An indirect electrochemical reduction and dyeing with indigo were carried out here to solve problems of low dye reduction rate and poor dyeing depth in the current electrochemical dyeing process.

Response surface analysis tests were performed to evaluate the effects of ferrous sulfate concentration, medium concentration, sodium hydroxide concentration and reduction time on the reduction efficiency of indirect electrochemical reduction of indigo.

The conditions obtained by design-expert optimization showed that the concentration of FeSO₄·7H₂O has the most significant effect on the reduction performance of dye liquor. Under the optimized electrochemical reduction dyeing process, the rate of dye reduction could be reached 91.21 per cent and the K/S value of indirect electrochemical dyeing of indigo can be achieved to 12.96, which is increased by about 9.56 per cent compared with that of Na₂S₂O₄ dyeing with the same color fastness basically.

The recyclability and biodegradability of the dye remain to be explored.

The strategy presented here can be developed to replace a substantial part of electrochemical dyeing with optimized product quality and reduced environmental pollution in denim production.

The strategy presented here can be developed to replace a substantial part of electrochemical dyeing with optimized product quality and reduced environmental pollution in denim production.

Application of the Fe(II)-DGS-Abal B complex media system in the indirect electrochemical reduction of indigo.

Indirect electrochemical oxidation and electro-flocculation were combined to degrade indigo wastewater.

The degradation efficiency of indigo wastewater in single-cell and double-cell were investigated. Based on the previous single factor experiments, the oxidative degradation conditions of indigo wastewater in single cell were optimized by response surface methodology (RSM). The decolorization rate, chemical oxygen demand (COD) removal rate, the contents of flocculation precipitation and indigo were measured and analyzed.

The degradation efficiency in single cell was higher than in double cell. The electrolysis conditions were optimized by RSM and the decolorization rate was 99.01% with COD removal rate of 60.34% and conductivity of 89.75 mS/cm. The amount of flocculated precipitation decreased by 53.33% and the indigo increased by 86.34%. The content of Na and S decreased by 12.13 and 6.49%, respectively. The ratio of Fe3+ to Fe2+ in the solution was 4.62:1, indicating that most of the iron dropped on the electrode sheet was converted to Fe3+.

The one-step electrochemical oxidation and flocculation method with the advantages of simple operation and environmental protection, provided a reference for the actual treatment of dyeing wastewater.

Combining the electrochemical flocculation and oxidation provided an efficient and practical solution for degradation of indigo wastewater.

Combining the advantages of electrochemical oxidation and electroflocculation, the application of electrochemistry in printing and dyeing wastewater treatment technology has been expanded.

Sulfate-reducing bacteria (SRB) are recognized by scholars as the most important class of bacteria leading to corrosion of metal materials. It is important to use the properties of microorganisms to inhibit the growth of SRB in the corrosion protection of metal materials and to protect the environment.

In this work, the behavior of anaerobic Thiobacillus denitrificans (TDN) intracellular enzyme inhibition of SRB corrosion of EH36 steel was investigated with electrochemical impedance spectroscopy, biological detection technology and X-ray photoelectron spectroscopy.

Results showed that the SRB crude intracellular enzyme affected the corrosion behavior of EH36 steel greatly and the purified TDN intracellular enzyme inhibits SRB intracellular enzyme corrosion to EH36 steel.

A perfect enzyme activity inhibition mechanism will provide theoretical guidance for the selection and application of anticorrosion microorganisms, which is of scientific significance in the field of microbial anticorrosion research.

The dispersity of graphene oxide (GO) has an important effect on the properties of epoxy resin (EP) composites. Many modification and dispersion methods require the use of inert solvents which do not participate in the modification reaction, although GO can be uniformly dispersed in water and alcohol solvents. Based on this requirement, several inert solvents were selected as dispersion solvents to find out the suitable inert solvent for GO dispersion into EP matrix.

Several inert solvents with different solubility parameters were selected as dispersion solvents to prepare GO/EP composite. The microstructure, mechanical properties, insulation properties, dielectric properties and thermal property of the composite were characterized, which was due to find suitable inert solvent for GO dispersion into EP matrix.

The dispersity of N, N-dimethylformamide (DMF) was the best stable suspension state when it was used as solvent instead of occurring sedimentation and agglomeration. Moreover, DMF was further confirmed as a suitable inert solvent for the dispersion of GO into EP according to the mechanical properties, insulation properties and thermal conductivity characterization.

The dispersion of GO in solvents has already been researched, but the traditional solvents, such as alcohols and water, has shown their limitations with the increase of modification methods, which were not suitable for the modification environment such as cyanate graft modification. Therefore, it was very important to choose a kind of inert solvent for dissolving EP matrix and dispersing GO better.

Several inert solvents were used to disperse GO into EP, and the influence of different dispersing solvents on the adhesive was discussed through the analysis of the mechanical properties, insulation properties and thermal conductivity, which was due to explore the inert solvent suitable for GO dispersion.

Radical innovation involves significant technological advances that have a critical impact on both firm growth and society development. Therefore, there is a growing need to understand how to achieve radical innovation. While previous studies have examined the direct effect of digitization on firm innovation, there is still limited knowledge of how digitization affects radical innovation. This paper aims to contribute to further exploring the underlying mechanism of how digitization affects radical innovation by incorporating the serial mediation effect of absorptive capacity.

This paper collected data from Chinese-listed manufacturing firms from 2015 to 2021 and analyzed the data using bootstrap analysis.

The research results show that digitization has a positive impact on radical innovation. Furthermore, digitization can influence radical innovation through potential absorptive capacity and realized absorptive capacity, and the mediation effect of potential absorptive capacity and realized absorptive capacity can occur sequentially. These research results are validated by a range of robustness tests.

This paper contributes to the literature on digitization and radical innovation by validating a model that links digitization through absorptive capacity to radical innovation. This model helps to explain the relationship between digitization and radical innovation, which has previously been a topic of debate. This paper also contributes to the absorptive capacity literature by unpacking the asymmetric roles of the potential absorptive capacity and the realized absorptive capacity. This paper also provides valuable implications for practices.

Although the literature has highlighted that a firm’s board is critical for firm innovation, the impact of board characteristics on firm innovation has always been examined separately, leading to inconclusive research results. Based on the complexity theory, this paper incorporates four board characteristics, including board size, board ownership, board independence and CEO duality, to examine the impact of the combinations of different board characteristics on firm innovation through qualitative comparative analysis.

Using the panel data of listed manufacturing firms in China from 2007 to 2022, this paper conducted the fuzzy set qualitative comparative analysis to test the proposed hypotheses.

The research results show that no single board characteristic can explain firm innovation, as board size, board ownership, board independence and CEO duality can lead to either positive or negative firm innovation. Moreover, firm innovation depends on a complex combination of board characteristics.

This paper makes the following contributions: Firstly, this paper advances the firm innovation literature by extending the role of board characteristics on firm innovation, thereby offering a new way to model firm innovation in terms of board characteristics. Secondly, this paper provides a more comprehensive account of the role of a firm’s board by integrating agency theory and resource dependence theory. Thirdly, this paper also identifies a promising avenue for further research in the field of corporate governance: the investigation of other contingency contexts in which the effect of board characteristics may be observed, with the aim of further increasing the understanding of board functioning.

This study empirically evaluates the effect of China’s 2016 Green Financial System (GFS) framework on corporate green development, focusing on the role of green investment in achieving sustainability.

This study uses a quasinatural experiment design to combine difference-in-difference and propensity score matching methods for analysis. It examines 799 polluting and 1,130 nonpolluting firms from 2013 to 2020, enabling a comprehensive assessment of the GFS framework’s influence.

This study affirms a statistically significant positive influence of the GFS framework on escalating green investment levels in polluting firms. Robust sensitivity analyses, encompassing parallel trend assessment, entropy balancing test, and alternative proxies, corroborate these findings. A mediation analysis identifies the implementation of an environmental management system as the potential underlying mechanism. A cross-sectional analysis identifies high financial slack, high profitability, mandatory CSR regulations, and marketization level as the influencing factors.

The study’s findings have critical implications for policymakers, regulators, and companies. Demonstrating the effectiveness of the GFS framework in driving green investment underscores the importance of aligning financial systems with sustainability goals.

This study contributes novel empirical evidence on the positive effect of China’s GFS framework on corporate green development. The quasinatural experiment design, coupled with comprehensive sensitivity analyses, strengthens the robustness of the findings.

Traditional nondestructive failure localization techniques are increasingly difficult to meet the requirements of high density and integration of system in package (SIP) devices in terms of resolution and accuracy. Time domain reflection (TDR) is recognized as a novel positioning analysis technology gradually being used in the electronics industry because of the good compatibility, high accuracy and high efficiency. However, there are limited reports focus on the application of TDR technology to SiP devices.

In this study, the authors used the TDR technique to locate the failure of SiP devices, and the results showed that the TDR technique can accurately locate the cracking of internal solder joints of SiP devices.

The measured transmission rate of electromagnetic wave signal was 9.56 × 107 m/s in the experimental SiP devices. In addition, the TDR technique successfully located the failure point, which was mainly caused by the cracking of the solder joint at the edge of the SiP device after 1,500 thermal cycles.

TDR technology is creatively applied to SiP device failure location, and quantitative analysis is realized.

The purpose of this paper is to examine (a)symmetric features of task-technology-performance characteristics that are most relevant to fit, satisfaction and continuance intention of using apps in mobile banking transactions.

Exploratory factor analysis was used with maximum likelihood extraction and Varimax rotation on a separate sample of 183 mobile banking apps users prior to the main data collection. The theoretical model was tested applying a factor-based structural equation modelling approach to a sample of 250 experienced mobile banking apps users.

The study unveiled that the task and performance characteristics are more relevant compared to technology characteristics when doing transactions via apps. In addition, the findings uncovered that user satisfaction and continuous intention to use apps stem from the degree of fit in online transactions. The findings of moderation analysis highlighted that users in the lower income group are more concerned about the performance characteristics of banking apps, and there are no differences across age and gender groups. Surprisingly, technology characteristic has a nonlinear nature and this study shows potential boundary conditions of technology characteristics in degree of fit, user satisfaction and continuance intention to use apps.

Findings from the conditional probabilistic queries reveal that with 83.3 per cent of probability, user satisfaction is high when using apps for banking transactions, if the levels of fit, task, performance and technology characteristics are high. Furthermore, with 72 per cent of probability, continuance intention to use apps is high, if the levels of performance and task characteristics are high.

Contributing to task-technology fit theory, this study shows that performance characteristics need to be aligned with task and technology characteristics in order to have better fit when using apps for online banking transactions.