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The loading mechanism of textures considering turbulence has not been fully covered. This paper aims to investigate the effect of turbulence on the textured loading capacity under water lubrication and to analyze the causes of the turbulence effect.

Computational fluid dynamic models with different textured shapes are established after validation. The transition shear stress transport (SST) model, which is suitable for predicting the transition process of fluid from laminar state to turbulent state, is adopted in the present study. To illustrate the effect of turbulence, the loading capacity of textures predicted by transition SST model and laminar model is compared.

The loading capacity is higher after considering turbulence because more lubricant enters into textures and the flow rate of lubricant to textured outlet increases. There exists an optimal textured depth ratio and density for loading capacity and the change of flow state would not affect the optimal values. The degree of fluid blockage at textured outlet has a dominant influence on loading capacity. As the textured shape changes to triangle or ellipse from rectangle, the vortices at the textured bottom move forward and the blockage at a textured outlet is enhanced, which makes loading capacity improved under the action of blocking effect.

The enhancement of the blocking effect is found to be crucial to the improvement of textured loading capacity after considering turbulence. Present research provides references to understand the loading mechanism of textures under turbulent conditions.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0149/

The purpose of this paper is to study the effective procedure for blocking and deblocking isocyanate by sodium bisulphite with special cosolvent and dropwise method.

A number of analytical techniques, including Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and Thermo gravimetric analyser (TGA) were employed to assess the reactions between isocyanates and sodium bisulphite, water, cosolvent, also the deblocking temperature of blocked isocyanates.

The blocked isocyanates reacted with sodium bisulphite, water and cosolvent via a special procedure. It was found that the − NCO functional groups of the isocyanates were completely blocked by sodium bisulphite and a new method for determining the lowest deblocking temperature of the blocked isocyanates was described. It was revealed that the deblocking temperature of blocked isocyanates by sodium bisulphite was lower than others.

The paper provides some useful information about the blocking and deblocking of isocyanate, which would be helpful for the preparation of blocking and deblocking isocyanate, and guiding the practical applications of blocked isocyanate.

The investigation found that the sodium bisulphite was a very efficient blocking agent for isocyanates at the room temperature via the special procedure developed. On the basis of emulsion polymerisation theory, polymer isocyanates were blocked by sodium bisulphite, which realised the new breakthrough effectively by means of controlled temperature, stirring speed and optimum dropwise speed in the whole reaction system. Meanwhile, the special cosolvent could improve the intermiscibility of isocyanate in sodium bisulphite aqueous solution, reduce the side reaction of isocyanate with water and accelerate reaction rate of isocyanate with sodium bisulphite. If no cosolvent was present, the blocked system would not be homogeneous.

The mechanisms of the deblocking reaction of the polyurethane with blocking agent were investigated in detail relatively using thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FTIR) and X-ray photoelectron spectroscopy (XPS). This kind of method for polyurethane as the application of wood adhesives can provide the conditions of application and the main theoretical basis.

The blocking rate and latex particle size distribution were determined using the titrimetric analysis and the laser particle analysis, respectively. TGA, FTIR, XPS and differential scanning calorimetry were used to investigate the deblocking temperature and time of the blocked isocyanate in detail.

The results indicated that the blocking rate was approximately 97 per cent and the average particle size was 360 nm. The results of laser particle analysis have confirmed that the dispersivity of the blocked polyurethane emulsion was good. XPS results showed that the amount of –O = C-N-benzyl groups increased with an increasing deblocking temperature and subsequently reached equilibrium. In summary, the blocked isocyanate was deblocked at temperatures ranging from 50 to 90°C.

An important approach in future wood adhesive work would be to gain access to man-made board application data.

The paper provided some useful information about deblocking mechanisms of blocked polyurethane that would be helpful to guide applied practical applications as wood adhesive.

To promote China’s wood processing technology progress and solve the problem of shortage of the natural quality of wood is of important practical significance.

The paper is the first to use the XPS characterisation method to characterise deblocking polyurethane solution.

Group Support Systems (GSS) have been used and studied in the support of facilitated ideation sessions for years. The norm for these sessions has been for participants to work individually at GSS workstations. A review of applicable literature suggests that pairing participants at GSS workstations could result in higher quality ideas and participant satisfaction. This paper reports the results of a lab experiment that tested for differences between paired and unpaired facilitated GSS sessions. These results suggest that pairing participants can yield higher quality ideas from facilitated ideation without negative consequences.

The aim of the paper is to develop a method to block hydroxyl groups of epoxy acrylate (AAEP) in vinyl ester resin (VER) and to study the influence of modified VER on polyurethane/(VER) interpenetrating polymer network (PU/VER IPN).

The hydroxyl groups of AAEP in VER were blocked via different methods. Infra‐red spectroscopy was adopted to study the influence of the reagents, reaction temperature and feed molar ratio on the blocking effect of hydroxyl groups and the optimised technological parameters were determined. The PU/VER IPN and PU/modified VER IPN were prepared by simultaneous interpenetrating of VER (mixture of AAEP and butyl methacrylate with the mass ratio of 2/1) or modified VER and synthesised PU in their laboratory. The microstructure, dynamic mechanical properties and mechanical properties of PU/VER IPN and PU/modified VER IPN were compared.

The results showed that compared to unmodified IPN, because the hydroxyl groups in VER were blocked and no chemical cross‐linked structure existed between the two networks, the modified IPN showed dual‐continuous microsturcture with larger phase domain sizes between 20 and 50 nm. The effect damping temperature range of modified IPN was broadened and its damping performance was improved. The mechanical strength of modified IPNs decreased and their break elongation increased evidently.

The PU/modified VER IPN with excellent damping properties can be used in the applications where reduction of vibration and noise is desired.

The PU/modified VER IPN, in which no chemical cross‐linked structure existed between the two networks, was novel and its damping performance was improved and excellent.

This paper tests whether employers responded particularly negatively to African American job applicants during the deep U.S. recession that began in 2007. Theories of labor queuing and social closure posit that members of privileged groups will act to minimize labor market competition in times of economic turbulence, which could advantage Whites relative to African Americans. Although social closure should be weakest in the less desirable, low-wage job market, it may extend downward during recessions, pushing minority groups further down the labor queue and exacerbating racial inequalities in hiring. We consider two complementary data sources: (1) a field experiment with a randomized block design and (2) the nationally representative NLSY97 sample. Contrary to expectations, both analyses reveal a comparable recession-based decline in job prospects for White and African American male applicants, implying that hiring managers did not adapt new forms of social closure and demonstrating the durability of inequality even in times of structural change. Despite this proportionate drop, however, the recession left African Americans in an extremely disadvantaged position. Whites during the recession obtained favorable responses from employers at rates similar to African Americans prior to the recession. The combination of experimental methods and nationally representative longitudinal data yields strong evidence on how race and recession affect job prospects in the low-wage labor market.

Due to the predicted global temperature rise and local expansion and densification of cities, Urban Heat Islands (UHI) are likely to increase in the Netherlands. As spatial characteristics of a city influence its climate, urban design could be deployed to mitigate the combined effects of climate change and UHIs. Although cities are already experiencing problems during warm-weather periods, no clear spatial means or strategies are available for urban designers to alleviate heat stress. The paper aims to discuss these issues.

There is a lack of knowledge on cooling effects that can be achieved through urban design in Dutch neighbourhoods. In this paper, the cooling effects of various design measures are compared on the level of urban blocks and neighbourhoods, with a focus on a 1960s neighbourhood in Amsterdam-West. The cooling effects are simulated by means of the microclimate model ENVI-met, here the effects on air temperature and physiological equivalent temperature will be evaluated.

The use of green, and a higher roof albedo in particular, seem to perform well as cooling measures. Combinations of cooling measures do not necessarily result in better performance and might even counteract other cooling effects. However, combinations of measures that lead to an increase in the environmental temperature show the largest heating.

Effects of green roofs and facades are beyond the scope of this study, though future suggestions for this research will be included.

The results add to the body of knowledge in the area of climate design enabling policy makers and designers to estimate the effect of simulated measures in comparable neighbourhoods and thus improve thermal comfort in outdoor spaces.

The purpose of this study was to analyze the heat transfer in a square porous cavity that has a solid block placed at its center. The prime focus of this study is to investigate the effect of size of the square solid block and other physical parameters on the heat transfer rate from the hot surface into the porous medium. The left vertical surface of cavity is maintained at a hot temperature and the right vertical surface at a cool temperature, T_c. The finite element method is used to simplify the governing equations and is solved iteratively. It is noted that the size of the solid block plays a vital role in dictating the heat transfer from the hot surface to porous medium.

The current work is based on finite element formulation of a square porous cavity that has a solid square block placed at its center. Governing equations were solved iteratively.

The size of the solid block has a pronounced effect on the heat transfer behavior inside the porous cavity.

This study highlights the heat transfer due to a conducting square solid block at mid of porous cavity.

This paper aims to propose a design method for attenuating stress waves pressure using soft matrix embedded with particles.

Based on the phononic crystal theory, the particle composed of hard core and soft coating can form a spring oscillator structure. When the frequency of the wave is close to the resonance frequency of the spring oscillator, it can cause the resonance of the particle and absorb a lot of energy. In this paper, the resonant phononic crystal with three phases, namely, matrix, particle core and coating, is computationally designed to effectively mitigate the stress wave with aperiodic waveform.

The relationship between the center frequency and width of the bandgap and the geometric and physical parameters of particle core are discussed in detail, and the trend of influence is analyzed and explained by a spring oscillator model. Increasing the radius of hard core could effectively enhance the bandgap width, thus enhancing the effect of stress wave attenuation. In addition, it is found that when the wave is in the bandgap, adding viscosity into the matrix will not further enhance the stress attenuation effect, but will make the stress attenuation effect of the material worse because of the competition between viscous dissipation mechanism and resonance mechanism.

This study will provide a reference for the design of stress wave protection materials with general stress waves.

This study proposes a design method for attenuating stress waves pressure using soft matrix embedded with particles.

Neuroscientific technologies have begun to change the ways in which we understand, respond to, and treat drug addiction. According to addiction researchers, neuroscience marks a new era because of its potential to locate the causes of addiction within the brain and to treat addiction through altering neurochemistry. However, little is known about how addiction neuroscience and new neurochemical treatments shape individuals' experience of addiction and constitute new arrangements of knowledge and power that shape subjectivity and governance. This chapter addresses these domains by drawing on an analysis of scientific literature about addiction neuroscience and qualitative interviews with people being treated for addiction with buprenorphine, a pharmaceutical treatment for opioid dependence. The chapter charts four major themes in the addiction neuroscience literature (pleasure and the limbic system, rationality and the role of the prefrontal cortex, theories of plasticity, and the role of volition) and explores how each of these is incorporated, adapted, or rejected by individuals being treated for addiction with a pharmaceutical. This analysis demonstrates how neuroscientific ideas are mediated by the lived experiences of those being treated under a neuroscientific model. It also suggests that while neuroscientific interventions, like pharmaceuticals, shape the experience of those being treated for addiction, so too do many other forces, including social circumstances, moral frameworks, the drive for autonomy, and the quest to be “normal.”