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This paper aims to investigate the inhibition effect of sodium silicate (SS), sodium alginate (SA) and sodium tungstate (ST) on the corrosion behavior of AZ91D magnesium alloy in 3.5 per cent NaCl solution through polarization curve test at room temperature, electrochemical impedance spectroscopy and weight loss measurement.

The influence of SA concentration on the inhibition efficiency of the corrosion inhibitor was mainly analyzed. The corrosion morphology and inhibition mechanism of the samples were also analyzed with scanning electron microscopy and energy-dispersive spectroscopy.

The results show that with the increase of SA concentration, the corrosion inhibition first increases and then decreases. When SA concentration is 0.03 mol/L, the inhibition efficiency is the highest, reaching 98 per cent. The adsorption film formed by SA and other deposition films produce a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy.

The adsorption film formed by SA with other deposition films produces a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy. With the increase of SA concentration, the corrosion inhibition first increases and then decreases. When the concentrations of SA, SS and ST are 0.03 mol/L, 0.015 mol/L and 0.02 mol/L, respectively, the inhibition efficiency of the inhibitor is the highest, reaching 98 per cent.

The purpose of this paper is to explore the possibility of an enhanced continuous liquid interface production (CLIP) with a porous track-etched membrane as the oxygen-permeable window, which is prepared by irradiating polyethylene terephthalate membranes with accelerated heavy ions.

Experimental approaches are carried out to characterize printing parameters of resins with different photo-initiator concentrations by a photo-polymerization matrix, to experimentally observe and theoretically fit the oxygen inhibition layer thickness during printing under conditions of pure oxygen and air, respectively, and to demonstrate the enhanced CLIP processes by using pure oxygen and air, respectively.

Owing to the high permeability of track-etched membrane, CLIP process is demonstrated with printing speed up to 800 mm/h in the condition of pure oxygen, which matches well with the theoretically predicted maximum printing speed at difference light expose. Making a trade-off between printing speed and surface quality, maximum printing speed of 470 mm/h is also obtained even using air. As the oxygen inhibition layer created by air is thinner than that by pure oxygen, maximum speed cannot be simply increased by intensifying the light exposure as the case with pure oxygen.

CLIP process is capable of building objects continuously instead of the traditional layer-by-layer manner, which enables tens of times improvement in printing speed. This work presents an enhanced CLIP process by first using a porous track-etched membrane to serve as the oxygen permeable window, in which a record printing speed up to 800 mm/h using pure oxygen is demonstrated. Owing to the high permeability of track-etched membrane, continuous process at a speed of 470 mm/h is also achieved even using air instead of pure oxygen, which is of significance for a compact robust high-speed 3D printer.

Under oil interruption, lubricant supply in the high-speed bearing cavity is interrupted, which reduces the bearing lubrication and cooling ability, thus leading to degradation of bearing performance or even its failure. This paper aims to study the effect of grooves at the noncontact outer ring area on the flow and thermal performance of high-speed bearings under oil interruption, which is expected to improve the resistance of existing bearings to oil interruption.

The groove was added to the noncontact outer ring area of the bearing, and a method of combining volume of fluid and MRF was adopted to systematically study and analyze the oil-gas flow field structure and the temperature field distribution in the bearing cavities.

Results show that the lubricating oil could be stored and guided by the grooves of the bearing outer ring into the key lubrication area inside the bearing cavity, which increased the oil content near the inner ring and made the oil distribution more uniform. As a result, lubrication cooling and heat dissipation performance of the bearing cavity was improved. Compared with the original bearing, the bearing with a V-shaped groove had the optimal lubrication and cooling performance.

A rolling bearing model of the noncontact outer ring area with grooves under oil interruption is established in the paper. The simulation results provide theoretical guidance for the research and development of high-speed bearings with stronger oil interruption resistance ability.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0199/

The purpose of this paper is to propose a new stabilized finite volume element method for the Navier-Stokes problem.

This new method is based on the multiscale enrichment and uses the lowest equal order finite element pairs P₁/P₁.

The stability and convergence of the optimal order in H¹-norm for velocity and L²-norm for pressure are obtained.

Using a dual problem for the Navier-Stokes problem, the convergence of the optimal order in L²-norm for the velocity is obtained. Finally, numerical example confirms the theory analysis and validates the effectiveness of this new method.

The purpose of this paper is to determine conformity of geometrical parameters between the elements embroidered with photoluminescent threads and their digital images as well as to explore the change in photoluminescent radiation.

Using some different methodologies and apparatus, analysis shape of embroidered elements conformity and photoluminescent luminance attenuation are analysed.

The provided methodologies allow assessing the quality of embroidered elements area and photoluminescent properties.

The proposed approach can be adjusted to investigate photoluminescent properties of embroidered elements of different filling types.

Badaracco of Harvard Business School suggests a “nudge‐test‐escalate” (NTE) approach in influencing and implementing change. In The Book of Changes (I‐Ching), the most archaic and authoritative works of the Chinese classics, it adopts a “test‐accelerate‐forge” (TAF) approach instead. The purpose of this paper is to examine the similarities and differences between these two models, and addresses the effectiveness of influential leadership when the models are used in the western and eastern settings, respectively. It also looks at the fundamental concepts that underlie the models and discusses the characteristics and virtues that an influential leader must possess in order to make change happen.

The paper reviews the Harvard model by Badaracco and extracts taken from I‐Ching. It makes comparisons between the Chinese and Western perspectives.

The paper provides a discussion on the NTE and the TAF three‐step approaches in their leadership style to understand how western and Chinese leaders exert their power of influence. This paper argues that although each adopts a three‐step approach in its leadership style, the differences lie in the philosophies that are used to guide the leader in influencing others. From the Western perspective, there are three pertinent virtues of “restraint, modesty, and tenacity” in pushing through change, while the Chinese adopt the three virtues of “prudence, balance, and authority” as their essential guide in leadership and by exercising self‐restraint and patience, resonance, and balancing.

The paper presents the pertinence and applicability of the Harvard model and the Chinese model since there is an increase of frequency of cross‐cultural communication in government, business, education, and other organisations. One of the trends in research on leadership is on leaders' quality in relation to organisational ethics and competencies of effective communication.

This paper presents a high level of comparative analyses between two influential models. It points out the need for leaders in both the western and Asian organisations to be aware of the two models so as to enhance their competencies and capacities in maximising change. This paper argues that Harvard model is well designed and highly applicable; and that the Chinese classics on influential leaders are still relevant in today's contexts.

This paper aims to develop a house price forecasting model to investigate the impact of neighbourhood effect on property value.

Multi-level modelling (MLM) method is used to develop the house price forecasting models. The neighbourhood effects, that is, socio-economic conditions that exist in various locations, are included in this study. Data from the local government area in Greater Sydney, Australia, has been collected to test the developed model.

Results show that the multi-level models can account for the neighbourhood effects and provide accurate forecasting results.

It is believed that the impacts on specific households may be different because of the price differences in various geographic areas. The “neighbourhood” is an important consideration in housing purchase decisions.

While increasing housing supply provisions to match the housing demand, governments may consider improving the quality of neighbourhood conditions such as transportation, surrounding environment and public space security.

The demand and supply of housing in different locations have not behaved uniformly over time, that is, they demonstrate spatial heterogeneity. The use of MLM extends the standard hedonic model to incorporate physical characteristics and socio-economic variables to estimate dwelling prices.

This paper aims to introduce a novel approach to the fabrication of photoluminescent materials by coating rare earth aluminate luminescent materials on metallic substrates and a readily manufacturable light source with robust structure in the form of photoluminescent sphere (APS).

The clean and dried stainless steel sphere was sprayed with UH 2593, a white undercoat, the luminescent coating and the weather resistance coating in chronological order.

After adhered onto the stainless steel sphere, the peaks corresponding to the N-H stretching vibrations were changed. The intensity of free N-H stretching at 3,536 cm⁻¹ dramatically decreased and the peak of hydrogen-bonded N-H stretching of PU moved to lower wavenumbers. The red shift of the infrared bands of functional groups was attributed to the strengthened hydrogen bonding. The hydrogen bonding interactions between the stainless steel substrates and the polyurethane coating endowed the APS with excellent adhesive property and also promoted the evenly distribution of the photoluminescent particles in the polymer coating matrix.

This approach can be applicable in the fabrication of the photoluminescent materials. The APS can be used as signs and guiding post in remote areas without sufficient electricity supply and in the seas and rivers with complicated hydrological conditions.

This approach has provided a method to produce tough and durable luminescent signs for remote areas and dangerous seas and explained the functional mechanism of the combined application of metallic materials and non-metallic materials.

Promoting clean heating in rural areas is crucial for achieving a low-carbon transition of energy consumption and China's dual-carbon target. The study aims to consider the energy stacking behavior in heating energy use, reveals the determinants that affect household cleaner heating choices under the winter clean heating plan (WCHP), and proposes policy recommendations for the sustainable promotion of clean heating.

With unique rural household survey data covering the clean heating pilot regions in northern China in 2020, this study estimates the relationship between driving factors and heating energy choices through binary and multivariate probit models.

The regression estimates show that the main drivers of heating energy choices include household income per capita, education level of household head, knowledge of the WCHP, access to heating subsidies and perception of indoor air pollution. There is energy stacking behavior in rural household heating energy use. Household decisions to adopt electricity or clean coal heating are correlated with firewood or soft coal use.

This study is one of the few to investigate the heating energy use of rural households by allowing for the adoption of multiple energy types. Combined with a unique microsurvey dataset, it could provide rich information for formulating proper energy transition planning. The findings also shed light on the importance of heating subsidies, households' knowledge of WCHP and awareness of environmental health in choosing clean heating energy, which has not been fully valued in related research.

This paper aims to study the effect of processing parameters and the fundamental mechanism of surface morphologies during electron beam selective melting.

From the powder-scale level, first, the discrete element method is used to obtain the powder bed distribution that is comparable with the practical condition; then, the finite volume method is used to simulate the particle melting and flowing process. A physically reliable energy distribution of the electron beam is applied and the volume of fluid method is coupled to capture the free boundary flow. Twelve sets of parameters grouped into three categories are examined, focusing on the effect of scan speed, input powder and energy density.

According to the results, both melting pool width and depth have a positive relation with the energy density, whereas the melting pool length is insensitive to the scan velocity change. The balling effect is attributed to either an insufficient energy input or the flow instability; the hump effect originates from the mismatch between electron beam moving and the fluid flow. The scan speed is a key parameter closely related to melting pool size and surface morphologies.

Through a number of case studies, this paper gives a comprehensive insight of the parameter effects and mechanisms of different surface morphologies, which helps to better control the manufacturing quality of electron beam selective melting.