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This study aims to investigate the behavior of the green biomass-derived copper (lignin/silica/fatty acids) complex, copper lignin/silica/fatty acids (Cu-LSF) complex, when incorporated into the nonpolar ethylene propylene diene (EPDFM) rubber matrix, focusing on its reinforcing and antioxidant effect on the resulting EPDM composites.

The structure of the prepared EPDM composites was confirmed by Fourier-transform infrared spectroscopy, and the dispersion of the additive fillers and antioxidants in the EPDM matrix was investigated using scanning electron microscopy. Also, the rheometric characteristics, mechanical properties, swelling behavior and thermal gravimetric analysis of all the prepared EPDM composites were explored as well.

Results revealed that the Cu-LSF complex dispersed well in the nonpolar EPDM rubber matrix, in thepresence of coupling system, with enhanced Cu-LSF-rubber interactions and increased cross-linking density, which reflected on the improved rheological and mechanical properties of the resulting EPDM composites. From the various investigations performed in the current study, the authors can suggest 7–11 phr is the optimal effective concentration of Cu-LSF complex loading. Interestingly, EPDM composites containing Cu-LSF complex showed better antiaging performance, thermal stability and fluid resistance, when compared with those containing the commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline and N-isopropyl-N’-phenyl-p-phenylenediamine). These findings are in good agreement with our previous study on polar nitrile butadiene rubber.

The current study suggests the green biomass-derived Cu-LSF complex to be a promising low-cost and environmentally safe alternative filler and antioxidant to the hazardous commercial ones.

The type 120 emergency valve is an essential braking component of railway freight trains, but corresponding diaphragms consisting of natural rubber (NR) and chloroprene rubber (CR) exhibit insufficient aging resistance and low-temperature resistance, respectively. In order to develop type 120 emergency valve rubber diaphragms with long-life and high-performance, low-temperatureresistant CR and NR were processed.

The physical properties of the low-temperature-resistant CR and NR were tested by low-temperature stretching, dynamic mechanical analysis, differential scanning calorimetry and thermogravimetric analysis. Single-valve and single-vehicle tests of type 120 emergency valves were carried out for emergency diaphragms consisting of NR and CR.

The low-temperature-resistant CR and NR exhibited excellent physical properties. The elasticity and low-temperature resistance of NR were superior to those of CR, whereas the mechanical properties of the two rubbers were similar in the temperature range of 0 °C–150 °C. The NR and CR emergency diaphragms met the requirements of the single-valve test. In the low-temperature single-vehicle test, only the low-temperature sensitivity test of the NR emergency diaphragm met the requirements.

The innovation of this study is that it provides valuable data and experience for future development of type 120 valve rubber diaphragms.

This study aims to investigate the micro mechanism of macro rheological characteristics for composite modified asphalt.Grey relational analysis (GRA) was used to analyze the correlation between macro rheological indexes and micro infrared spectroscopy indexes.

First, a dynamic shear rheometer and a bending beam rheometer were used to obtain the evaluation indexes of high- and low-temperature rheological characteristics for asphalt (virgin, SBS/styrene butadiene rubber [SBR], SBS/rubber and SBR/rubber) respectively, and its variation rules were analyzed. Subsequently, the infrared spectroscopy test was used to obtain the micro rheological characteristics of asphalt, which were qualitatively and quantitatively analyzed, and its variation rules were analyzed. Finally, with the help of GRA, the macro-micro evaluation indexes were correlated, and the improvement efficiency of composite modifiers on asphalt was explored from rheological characteristics.

It was found that the deformation resistance and aging resistance of SBS/rubber composite modified asphalt are relatively good, and the modification effect of composite modifier and virgin asphalt is realized through physical combination, and the rheological characteristics change with the accumulation of functional groups. The correlation between macro rutting factor and micro functional group index is high, and the relationship between macro Burgers model parameters and micro functional group index is also close.

Results reveal the basic principle of inherent-improved synergistic effect for composite modifiers on asphalt and provide a theoretical basis for improving the composite modified asphalt.

This study evaluates the potential of using the material extrusion (MEX) process for recycling waste tire rubber (WTR). By investigating the process parameters, mechanical behaviour and morphological characterisation of a thermoplastic polyurethane-waste tire rubber composite filament (TPU-WTR), this study aims to establish a framework for end-of-life tire (ELT) recycling using the MEX technology.

The research assesses the impact of various process parameters on the mechanical properties of the TPU-WTR filament. Hysteresis analysis and Poisson’s ratio estimation are conducted to investigate the material’s behaviour. In addition, the compressive performance of diverse TPU-WTR triply periodic minimal surface lattices is explored to test the filament suitability for printing intricate structures.

Results demonstrate the potential of the TPU-WTR filament in developing sustainable structures. The MEX process can, therefore, contribute to the recycling of WTR. Mechanical testing has provided insights into the influence of process parameters on the material behaviour, while investigating various lattice structures has challenged the material’s capabilities in printing complex topologies.

This research holds significant social implications addressing the growing environmental sustainability and waste management concerns. Developing 3D-printed sustainable structures using recycled materials reduces resource consumption and promotes responsible production practices for a more environmentally conscious society.

This study contributes to the field by showcasing the use of MEX technology for ELT recycling, particularly focusing on the TPU-WTR filament, presenting a novel approach to sustainable consumption and production aligned with the United Nations Sustainable Development Goal 12.

The research aims to investigate the impact of thermo-mechanical aging on SBR under cyclic-loading. By conducting experimental analyses and developing a 3D finite element analysis (FEA) model, it seeks to understand chemical and physical changes during aging processes. This research provides insights into nonlinear mechanical behavior, stress softening and microstructural alterations in SBR compounds, improving material performance and guiding future strategies.

This study combines experimental analyses, including cyclic tensile loading, attenuated total reflection (ATR), spectroscopy and energy-dispersive X-ray spectroscopy (EDS) line scans, to investigate the effects of thermo-mechanical aging (TMA) on carbon-black (CB) reinforced styrene-butadiene rubber (SBR). It employs a 3D FEA model using the Abaqus/Implicit code to comprehend the nonlinear behavior and stress softening response, offering a holistic understanding of aging processes and mechanical behavior under cyclic-loading.

This study reveals significant insights into SBR behavior during thermo-mechanical aging. Findings include surface roughness variations, chemical alterations and microstructural changes. Notably, a partial recovery of stiffness was observed as a function of CB volume fraction. The developed 3D FEA model accurately depicts nonlinear behavior, stress softening and strain fields around CB particles in unstressed states, predicting hysteresis and energy dissipation in aged SBRs.

This research offers novel insights by comprehensively investigating the impact of thermo-mechanical aging on CB-reinforced-SBR. The fusion of experimental techniques with FEA simulations reveals time-dependent mechanical behavior and microstructural changes in SBR materials. The model serves as a valuable tool for predicting material responses under various conditions, advancing the design and engineering of SBR-based products across industries.

This study aims to examine why women transition from wage work to self-employed entrepreneurship, the seemingly insecure and unruly economic sector compared with the stable iron rice bowl and the fancy spring rice jobs.

Based on in-depth interviews in Zhejiang, the entrepreneurial hotbed in coastal China, this study examines the experiences of self-employed female entrepreneurs who used to work in the iron rice bowl and the spring rice jobs and explores their nonconventional career transition and its gendered implications.

This study finds that these women quit their previous jobs to escape from gendered suppression in wage work where their femininity was stereotyped, devalued or disciplined. By working for themselves, these women embrace a rubber rice bowl that allows them to improvise different forms of femininity that are better rewarded and recognized.

The study contributes to studies on gender and work by framing femininity as a fluid rather than a fixed set of qualities and fills the research gap by illustrating women’s agency in reacting to gender expectations in certain workplaces. The study develops a new concept of rubber rice bowl to describe how entrepreneurship, a seemingly women-unfriendly sphere, attracts women by allowing them to comply with, resist, or improvise normative gender expectations.

The purpose of this paper is to introduce a variable distance pneumatic gripper with embedded flexible sensors, which can effectively grasp fragile and flexible objects.

Based on the motion principle of the three-jaw chuck and the pneumatic “fast pneumatic network” (FPN), a variable distance pneumatic holder embedded with a flexible sensor is designed. A structural design plan and preparation process of a soft driver is proposed, using carbon nanotubes as filler in a polyurethane (PU) sponge. A flexible bending sensor based on carbon nanotube materials was produced. A static model of the soft driver cavity was established, and a bending simulation was performed. Based on the designed variable distance soft pneumatic gripper, a real-time monitoring and control system was developed. Combined with the developed pneumatic control system, gripping experiments on objects of different shapes and easily deformable and fragile objects were conducted.

In this paper, a variable-distance pneumatic gripper embedded with a flexible sensor was designed, and a control system for real-time monitoring and multi-terminal input was developed. Combined with the developed pneumatic control system, a measure was carried out to measure the relationship between the bending angle, output force and air pressure of the soft driver. Flexible bending sensor performance test. The gripper diameter and gripping weight were tested, and the maximum gripping diameter was determined to be 182 mm, the maximum gripping weight was approximately 900 g and the average measurement error of the bending sensor was 5.91%. Objects of different shapes and easily deformable and fragile objects were tested.

Based on the motion principle of the three-jaw chuck and the pneumatic FPN, a variable distance pneumatic gripper with embedded flexible sensors is proposed by using the method of layered and step-by-step preparation. The authors studied the gripper structure design, simulation analysis, prototype preparation, control system construction and experimental testing. The results show that the designed flexible pneumatic gripper with variable distance can grasp common objects.

Industries worldwide have been striving to serve the increasing demand of consumers alongside providing importance to environmental issues. Yet, there are concern-raising changes on the planet, such as greenhouse gas (GHG) emissions resulting in a temperature rise. India remains a vital party of the United Nations Convention on Climate Change. Henceforth, the paper aims to study the increased emissions of GHG in Puducherry, an Indian Union Territory that faces tremendous pressure owing to its denser population.

The research is designed as a case study conducted in a tyre manufacturing unit in Puducherry. The industrial sector was chosen, as it is the largest contributor (78%) of the total GHG emissions. Case studies were chosen to analyse the GHG emissions and the effects of implementing the policies and imposing interventions over time. The identified areas of improvement, proposed changes and the implemented ones with the results over a three-year period have been discussed.

The present study’s GHG inventorisation for Puducherry paved the way for preparing mitigation and adaptation plans. A total of 21 and 48 changes were incorporated to conserve fuel and power, respectively. A significant 11% reduction in power consumption and 1,113,008/litres of furnace oil was achieved. This translates to 5,115 tCO₂ and 3,306 tCO₂, respectively.

This research will help to improve the importance of climate change management in the manufacturing sector, and it will pave the way for achieving effective sustainable practices.

Such case studies could cumulatively impact the policy directives/ interventions on GHG emissions. Though this seems a small leap, putting them into practice at firm levels would contribute significantly towards achieving Sustainable Development Goals.

This study aims to explore the managerial conception of the determinants and barriers of sustainability integration into management control systems (MCS) of manufacturing companies in Sri Lanka. Although existing literature has explored the factors that influence the adoption of specific management controls to handle environmental and social issues, the role of management conception has been underrepresented. Specifically, literature is scarce in identifying contextual and organisational factors that influence corporates beyond mere adoption of controls but to integrate with regular controls, especially in developing countries such as Sri Lanka.

A multiple case study approach has been used to identify the management conception of barriers and enablers for sustainability control integration. The analysis is conducted based on a theoretical framework extending the work of Gond et al. (2012) and George et al. (2016). To obtain an in-depth and multifaceted view, semi-structured interviews were conducted with managers in charge of different functional departments of five manufacturing companies.

The findings identified managers’ perceived factors, such as environmental impact, stakeholder pressure (customer, competitor and regulatory authorities) and top management commitment, showing a clear difference between strongly and weakly integrated companies. Contrary to the literature, domestic regulatory pressure and multinational ownership do not sufficiently drive MCS sustainability integration.

The findings have implications for managers and practitioners to anticipate the potential barriers and determinants of sustainability integration and provide guidance to take proper measures to deal with them when designing and implementing their MCS.

The study adds value to the literature by presenting a theoretical framework based on the triangulation of different theories to recognise the significance of management idea in sustainable integration. Furthermore, because sustainable integration of MCS is a novel idea, this research is one of the earlier attempts to highlight problems from the perspective of developing countries.

As Czech export is widely considered the key to the economic development of Czechia, this chapter explores the relationship between microeconomic profitability among companies in selected TOP10 export industries and the macroeconomic development of the export itself. An investigation was carried out to compare the differences caused by the COVID-19 pandemic. In addition, the comparison is developed according to the size and concentration of ownership among exporting companies. Annual data are obtained from the Bureau van Dijk Orbis database to analyse profitability among 4,283 companies in 10 NACE industries from 2012 to 2021. We have obtained encouraging results, demonstrating that not only those less profitable companies affected export development. However, in general, our results emphasise the importance of those less profitable medium-sized companies for Czech export, within the manufacture of machinery and equipment, and the manufacture of motor vehicles in particular.