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This paper aims to improve the general circuit of driving and protection based on insulated gate bipolar transistor (IGBT) in dielectric barrier discharge power supply by designing a novel half-bridge inverter circuit with discrete components.

With one SG3524 chip, the structure based on discrete components is used to design the IGBT drive circuit. The driving waveform is isolated and sent out by photo-coupler 6N137. The protection circuit is realized by Hall sensor directly detecting the main circuit current, supplemented by a few components, including diodes, resistors, capacitors and triodes. It improves the reliability of the protection circuit.

In the driving circuit, the phase difference of signals from two channels are 180°. Moreover, when the duty cycle is set at 40%, it can ensure sufficient pulse width modulation response time. In the protection circuit, when over-current occurs, an intermittent output signal is automatically sent out. Furthermore, the over-current response time can be controlled independently. The peak voltage can be adjusted continuously from 0 to 30 kV with its frequency from 8 to 25 kHz and the power output up to 150 W.

The novel circuit of driving and protection makes not only its structure simpler and easier to be realized but also key parameters, such as frequency, the duty cycle and the driving voltage, continuously adjustable. Moreover, the power supply is suitable for other discharges such as corona discharge and jet discharge.

As quality issues become more prominent in supply chain (SC) management, understanding the factors driving SC quality integration (SCI_Q) and quality performance has become increasingly important, shifting the focus of quality management to firms in SCs. This study aims to examine the role of SC quality leadership (SCQL) in facilitating SCI_Q and its direct and indirect relationship with quality performance.

Data on 400 Chinese manufacturing firms were collected using survey questionnaires. The hypothesised relationships between SCQL, SCI_Q and quality performance were tested using structural equation modeling in AMOS 22.0.

Empirical results show that SCQL has a positive and significant effect on quality performance and all three dimensions of SCI_Q: supplier quality integration, internal quality integration and customer quality integration. The results also show that SCI_Q mediates the relationship between SCQL and quality performance.

Executives should develop SCQL to improve SCI_Q in their SCs and ultimately improve quality performance. In particular, nurturing SQI can potentially lead to unique capabilities, relative to competitors. They should be aware of their important role in integrating and coordinating between functional units within the firm and between SC members.

This study enriches the SCM literature by identifying SCQL as a new and significant antecedent of SCI_Q in manufacturing firms. It contributes to the SC leadership literature by conceptualizing both the quality and social responsibility aspects of SC leadership, conceptualizing SCQL at the firm level and positioning SCI_Q as a mediator between SCQL and quality performance.

The purpose of this paper is to develop a coated glass fiber fabric which can be used as the outer shell of firefighters' protective clothing and replace aramid fabric.

The silicone resin with excellent heat resistance was selected as the base solution. Silica nanoparticles, mica powder and ferric oxide were added into the coating solution, which was coated on the glass fiber fabrics. The vertical burning, thermal protective performance (TPP) value, second-degree burn time and water repellency of the coated fabrics were characterized.

Results showed that the dosages of the thickening filler were in the range 4%–6%; the coating solution has good viscosity. The optimal composition of fillers added in the silicone resin is silica nanoparticles 6%, ferric oxide 5% and mica powder 6%. The TPP value of the optimum coated fabric is 413 kW·s/m². The second-degree burn time is 4.98 s, which is obviously higher than that of the original glass fiber fabric (3.49 s) and that of the aramid fabric (3.82 s). The coated fabric has better thermal stability than aramid fabric.

The production cost of this coated glass fiber fabric was much lower than that of the aramid fabric.

The purpose of this paper is to investigate the effect of mullite on the mechanical properties and friction of carbon fiber (CF)-reinforced friction material.

CF-reinforced friction materials with varying content of mullite were fabricated by hot press molding, and then the tribological properties were tested on the MRH-3-type tribometer under ambient conditions with the ring-on-block configuration.

The experimental results indicated that the addition of mullite increased the density and compressive strength of friction material. However, the flexural strength of friction material decreased by 16% with the addition of 15 Wt.% mullite. The friction coefficient was proportional to the mullite content. Friction material with 12.5 Wt.% mullite showed the highest friction stability under different loads, whereas friction material with 10 Wt.% mullite exhibited the highest friction stability under different sliding speeds.

By boosting the resistance to deformation under load and increasing the specific heat capacity, mullite contributed significantly to the friction stability of the friction material.

For nanostores, striving to become the community group-buying leader is gaining prominence. This paper aims to construct Hotelling linear models to investigate whether nanostores should be registered as leaders and their decisions in a competitive environment.

This paper constructs three Hotelling linear models: neither nanostore registers as community leader, only one nanostore registers as community leader and both nanostores register as community leader. The competitive operation strategies of two general nanostores under three scenarios are solved.

The study finds that nanostores without a cost advantage may benefit from being the first leader. The nanostore's preferred decisions depend on the investment cost parameters of its own and competitors which may lead to market share competition. Furthermore, consumers' sensitivity to community group-buying service has a negative effect on nanostores' profit.

The study is one of the few to consider the competition between community leaders. Besides, the study considers that the utilities functions of consumers are concurrently impacted by the service decisions, along with the price in different nanostores. It can provide nanostores useful implications in the dynamic industry.

This study examines how board characteristics influence air, water and renewable energy (AWR) disclosures in an emerging economy. It argues for the necessity of separating these disclosures to address unique environmental impacts and stakeholder concerns.

Using longitudinal data from environmentally sensitive firms (2014–2022), a disclosure index based on the Global Reporting Initiative (GRI) framework was developed to quantify AWR separately. To address potential statistical issues such as endogeneity and selection bias, the analysis employed a set of robust regression models, including the industry fixed effects (FE) model, a lagged model and a two-stage least squares (2SLS) model.

Board size and audit committees positively influence all AWR disclosures, while foreign directors significantly impact air and renewable energy disclosures. Board meetings negatively affect water disclosures. Surprisingly, board independence shows no significant impact, and gender diversity has no notable relationship. Post-amendment, firms increased AWR disclosures, though participation remains limited.

Grounded in legitimacy theory, this study contributes to the literature by demonstrating how separating the unique characteristics of AWR disclosures offers stakeholders more precise insights into how firms manage specific environmental concerns. The findings are based on data from listed firms in Bangladesh and may not be generalisable to unlisted firms or other regions.

The study emphasises the importance of distinct AWR reporting, offering valuable insights for regulators and corporate boards to improve transparency and sustainability practices.

Separating AWR disclosures provides stakeholders with clearer assessments of firms' environmental performance, promoting accountability and informed decision-making.

This study uniquely emphasises the need for disaggregating air, water and renewable energy disclosures in emerging economies. By focussing on each environmental issue separately, the research highlights how distinct disclosures offer clearer insights into how firms address specific environmental challenges, such as air pollution, water management and the transition to renewable energy sources. This disaggregation is essential for stakeholders – particularly regulators, investors and policymakers – to assess and respond to firms' sustainability efforts accurately.