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The purpose of this paper is to provide additive manufacturing-based solutions for preparation of elastomeric foam with broaden compressive stress plateau.

Mechanic models are developed for obtaining designs of foam cell units with enhanced elastic buckling. An experimental approach is taken to fabricate the foams based on direct ink writing technique. Experimental and simulation data are collected to assist understanding of our proposals and solutions.

A simple tetragonal structured elastomeric foam is proposed and fabricated by direct ink writing, in which its cell unit is theoretically designed by repeating every four filament layers. The foam exhibits a broader stress plateau, because of the pronounced elastic buckling under compressive loading as predicted by the authors’ mechanic modeling. A two-stage stress plateaus as observed in the foam, being attributed to the dual elastic buckling of the cell units along two lateral directions of the XY plane during compression.

Future work should incorporate more microscopic parameters to tune the elastomeric foam for mechanic performance testing on linear elastic deformation and densification of polymer matrix.

Additive manufacturing offers an alternative to fabricate elastomeric foam with controlled cell unit design and therefore mechanics. Our results comment on its broad space for development such superior cushioning or damping material in the fields of vibration and energy absorption.

This work has contributed to new knowledge on preparation of high performance elastomeric foam by providing a better understanding on its cell structure, being printed using direct ink writing machines.

This paper aims to examine the impacts of immigration processes on the HIV risk faced by mainland Chinese immigrants in Canada.

Drawn from a larger qualitative study on the vulnerability to HIV of recent immigrants to Canada, the data presented were collected through individual, face‐to‐face, semi‐structured, in‐depth interviews with 34 mainland‐Chinese immigrant adults who perceived themselves as facing sexual health risks (including HIV infection) through engaging in unsafe sex.

Immigration processes have not only exposed these immigrants to a HIV risk that they did not face in China; they have also compromised their capacity to effectively respond to it. In light of various settlement difficulties, HIV risk is neither the only nor the most urgent challenge that they have faced in their post‐immigration lives.

The HIV risk under discussion must be understood by situating it in the processes of immigration, settlement, and transnational connections, all of which have shaped not only the dynamics of HIV risk but, also, these individuals' capacities to respond to that risk. Owing to its small‐size purposive sample, the results of this study may not be generalizable for Chinese immigrants in Canada as a whole.

Greater attention should be given to the intersections between immigrants' vulnerability to HIV and settlement processes and to holistic approaches that take into account the changing contexts and dynamics of HIV risk.

This exploratory study will contribute to knowledge of the HIV risk Chinese immigrants in Canada face – a little‐known topic.

The purpose of this paper is to investigate the tribological properties of a Cu–Cr–Zr alloy lubricated with acid rain.

The Cu 2.5 weight per cent–Cr-0.08 weight per cent–Zr alloy was produced in a vacuum induction furnace. The H₂SO₄ + H₂O, HNO₃ + H₂O and H₂SO₄ + HNO₃ + H₂O mixtures with pH of 5 were used as acid rain. Pure water was used as rain. The friction and wear properties of Cu–Cr–Zr alloy/American Iron and Steel Institute (AISI) 52100 steel couples lubricated with acid rain were investigated using a reciprocating ball-on-disc friction and wear tester (Optimol SRV, Germany). For investigating the properties of the alloy and wear scars, scanning electron microscopy, X-ray diffraction microscopy, energy dispersive X-ray spectrum, transmission electron microscopy and X-ray photoelectron spectroscope were used.

The wear rate of the Cu–Cr–Zr alloy lubricated with H₂O containing HNO₃ (pH = 5) was larger than pure water under the same conditions. The tribofilms containing Cu, Cr, Zr, S and N formed during sliding with acid rain, but corrosion also took place at that time.

The wear rate of the Cu–Cr–Zr alloy lubricated with H₂O containing HNO₃ (pH = 5) was larger than pure water, the wear and corrosion took place during sliding. As the trolley wires, the life of the Cu–Cr–Zr alloy was influenced by the environment.

The purpose of this paper is to study the behavior of smoke flow in a typical high-rise residential building fire in six common smoke control systems.

The pressure, temperature and CO₂ concentration were used to trace the motion of turbulent smoke flow through CFD.

It is found that the hot smoke could rise up and spread into the indoor space on the upper floors through the staircase. When the pressure in the evacuation staircase is higher, it would be more difficult for the smoke to enter the staircase and transport vertically. On the other hand, the smoke would soon transport to the indoor space on the upper floors horizontally. During this process, the smoke shows a more disorder horizontal transport under the sole effect of thermal buoyancy than the co-existence of thermal buoyancy and the air inlet.

Because of the chosen research approach, the research results may need to be tested by further experiments.

The paper includes implications for the design of smoke control systems and evacuation in a building fire.

This paper fulfils an identified need to study the behavior of smoke in a fire and optimize the design of smoke control systems.

This paper aims to construct evaluation index system of industrial economy-ecology-coordinated development based on “driving-force-pressure-state-impact-response” conceptual model. Grey target theory is introduced to evaluate industrial economy-ecology-coordinated development level and identify its key influencing factors. On that basis, the countermeasures are proposed to improve industrial economy-ecology-coordinated development in China.

Bull's-eye degree of grey target theory is introduced to evaluate industrial economy-ecology-coordinated development level of 31 provinces, municipalities and autonomous regions in China. The contribution degree of influence factors is analyzed by contribution degree theory.

The results show that first, the overall level of industrial economy-ecology-coordinated development in China is not high, there is a big gap of coordinated development level between provinces, municipalities and autonomous region, and there is still a large room to improve the status quo. Second, the major factors affecting industrial economy-ecology-coordinated development are gross industrial output value (GIOV) share of investment completed in the treatment of industrial pollution, common industrial solid wastes produced per GIOV, sulphur dioxide emission per GIOV, energy consumption per 10,000 yuan of gross regional product.

This paper constructs evaluation index system of industrial economy-ecology-coordinated development and applies grey target theory to evaluate industrial economy-ecology-coordinated development level and identify its key influencing factors.

The purpose of this paper is to synthesize a series of cyclophosphazene derivatives with better tribological properties.

To improve the adsorptivity to substrate, a series of cyclophosphazene derivatives substituted with ionic liquids were synthesized. The lubricity characteristics of phosphazene derivatives were evaluated on an Optimol SRV IV oscillating friction and wear tester. Scanning electron microscope and X‐ray photoelectron spectroscope analyses were conducted to examine the morphology and chemical composition of the wear scars and the possible tribochemical changes involved in the friction process.

Alkoxycyclophosphazene derivatives substituted with ionic liquids synthesized in the present work show better antiwear ability and load‐carrying capacity in steel‐steel contacts. The density of ion pairs plays an important role on tribological properties.

The paper deals with only a limited compounds and steel‐steel contacts. The paper works on the subject progressively to explore more combinations for better tribological properties.

All the cyclophosphazene derivatives present better tribological performance and could be used as base oils, such as hard disk surface lubricants.

Ionic liquids are introduced to cyclophosphazene derivatives in this paper. This is a new method to improve the tribological properties of cyclophosphazene derivatives.

The purpose of this paper is to study the tribological behavior and mechanism of water‐soluble bismuth dithiophosphate as the additive of water‐based cutting fluid in aluminum alloy tapping.

Comparable investigation has been made on the lubrication performance of bismuth dithiophosphate and sodium dithiophosphate in aluminum alloy tapping. The aluminum alloy‐machined surface finish was observed on scanning electron microscope. The films on the work‐piece‐machined surface and the tap tool working surface were analyzed by X‐ray photoelectron spectroscopy.

The results indicated that the water medium containing 1 wt% the prepared water‐soluble bismuth dithiophosphate exhibited better tapping efficiency than the liquid paraffin containing 2.5 wt% chlorinated paraffin and 2.5 wt% sulfurized olefin. The bismuth sulfide component in the reaction film on the tap working surface plays a leading role in elevating the tapping efficiency and improving the machined surface finish.

The paper is restricted to the lubrication performance of bismuth dithiophosphate as the water‐based cutting fluid additive in 2024 aluminum alloy tapping.

The test method adopted is very close to the machined method applied in industry. The test results show that the bismuth dithiophosphate can obviously improve the tapping efficiency and the machined surface finish. Thus, it can be applied to the aluminum alloy cutting in automotive and aviation.

An attempt has been made to identify the chemical reaction film sourced from bismuth element and dithiophosphate group on the work‐piece‐machined surface and the tool working surface and their contribution to enhancing the tapping efficiency and improving the machining surface finish. This is helpful to the designers and the practitioners of the additives of metalworking fluid.

The purpose of this paper is to understand the effect of base media on the tribological performance and tribochemistry of bismuth thiophosphate additive.

The oil‐water double soluble additive bismuth dithiophosphate was prepared and identified. The contributions of the two base media on the additive tribological behavior and the tribofilm components were comparatively studied.

The extreme pressure (EP) and friction‐reducing properties are remarkably improved with water substituted for paraffin as the base medium. The EP performance of the lubricating media containing this additive mainly results from the tribochemical reaction film on the rubbing surface, not from the viscosity of the base media. In water or paraffin medium, the adsorption process of this additive from the lubricant bulk onto the rubbing surface and the components and the properties of the tribochemical reaction films formed are different, which have important effect on the tribological performance.

The paper mainly focuses on how the water medium with polarity and the liquid paraffin base medium with non‐polarity affect on the tribological performance of the bismuth thiophosphate additive.

The research has found a water‐oil double soluble lubrication additive with outstanding EP and friction‐reducing performance.

The designed experiment provides a new approach to further learn the action mechanism of thiophosphate additive.

This study aims to explore how transformational leadership influences employees' creativity by considering the role of the environment and psychology. The study aims to provide insights into the impact of transformational leadership on team innovation climate, team reflexivity, psychological capital and employee creativity while also examining the moderating effect of environmental dynamism on these relationships.

This study employed a multi-source, multi-wave approach, utilizing data from 618 participants in 118 teams. It constructed a multilevel structural equation model and estimated the confidence intervals of the mediated and moderated effects using the Markov chain Monte Carlo method.

The results of the multilevel analyses indicated that transformational leadership positively influenced the team innovation climate, team reflexivity, psychological capital and employee creativity. Moreover, the study found that environmental dynamism positively moderates the relationships among transformational leadership, team reflexivity, psychological capital and employee creativity.

Drawing on social cognitive theory and the motivated information processing in groups model, this study offers new insights into the interplay between transformational leadership and creativity. It examines the moderating role of cross-level process linkages and environmental dynamism, thereby validating and extending relevant theories.

The purpose of this paper is to explain theoretically the relation between large shareholders, legal institutions, and capital structure, then empirically deduce how large shareholders and legal institution affected capital structure decision by integrating Chinese institutions.

This paper adopted cross‐section data of non‐financial listed companies in China and applied series of ordinary least square to empirically test the relationship between large shareholders, legal institution, and capital structure decision.

The empirical evidence provided by this paper indicates that large shareholders and legal institution do affect capital structure decision, specifically in seven areas.

This paper, based on the institutions of China, takes the largest shareholder, ultimately the controller, the relation of legal institution and capital structure into the research framework for the first time and systematically studies how the capital structure decision making is affected by the controlling shareholders, the nature of ultimately controllers, the concentration degree of shares held by a few large shareholders and legal institution. It is the first to empirically test whether the concentration degree of shares held by a few large shareholders and legal institution will affect the relation between controlling shareholders and capital structure, and compensates for the deficiencies in previous studies.