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The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.

This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.

There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.

It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.

The construction of industrial park in the current development model of circular economy has been widely regarded as one of the important modes of macroeconomic exploration all over the world. Therefore, the research on the application of multi-project management theory based on circular economy in the construction of industrial park was proposed in this paper. First, the circular economy and multi-project management theory were expounded in detail. Then, the geographical location of multi project management in Qingyuan recycled plastic industrial park in Guangdong Province and the distribution of each building community were explained. And on this basis, the construction of the park's production, plant areas, residential areas and the planning objectives after completion were analyzed in detail. On the basis of analysis, the multi project management model used in the park was explained. It is pointed out that the construction of the park should be based on its own planning and practical needs, and the appropriate multi project management model should be chosen.

The aim of this paper is to construct a device that simulated the seawater splash zone, dynamic waterline zone (splash zone) and full immersion zone. Localized corrosion of 2A12 aluminum alloy long-scale specimen was studied.

Corrosion morphologies before and after the corrosion product removal were used to identify corrosion intensity at full seawater immersion zone, dynamic waterline zone (splash zone) and atmospheric zone. The average depth and diameter of corrosion pits in the three zones were evaluated by three-dimensional optical microscopy. The impact of wetting time of the atmospheric zone on the localized corrosion was investigated.

Corrosion pits were observed on the surface on day 4 for the wetted atmospheric zone (Case 1), and on the surface on day 8 for the alternant wet/dry atmospheric zone (Case 2). The corrosion product layer on the surface for Case 1 was partially broken down while the layer on the surface for Case 2 was intact. Average pitting depth and pitting diameters for Case 1 were more serious than that for Case 2.

The above findings revealed that the humidity of the atmospheric zone had great impact on the localized corrosion of aluminum alloy at the seawater splash zone.

This paper aims to present wireless passive temperature sensors by using high-temperature stable polymer-derived silicoaluminum carbonitride (PDC-SiAlCN) ceramic materials.

In this paper, a novel PDC-SiAlCN ceramic was synthesized by using polyvinylsilazne and aluminum-tri-sec-butoxide as precursors. Then, PDC-SiAlCN was used as the sensing material to fabricate sensors. The sensors are based on a cavity resonator and an integrated slot antenna. The resonant frequencies of the sensors are determined by the dielectric constants of PDC-SiAlCN ceramic, which monotonically increase versus temperature.

The effect of sensor dimension on the performance of the sensors was investigated using simulation and experimental methods. The using temperature, reliability and sensing distance of the sensors were studied experimentally. The sensors performed measurement up to 1100°C with excellent reliability and repeatability. The sensing distance varied from 38 to 14 mm when the temperature increasing from 20°C to 1100°C.

PDC-SiAlCN ceramic based wireless passive temperature sensors have the advantage of seamless integration of slot antennas and resonators, which greatly reduces the size of the sensor, reduces the direction of antenna transmission and increases the transmission space. The sensors can be used for many harsh environment applications such as engine monitoring.

The purpose of this paper is to investigate coexistence of multiple distribution systems in property‐casualty (P/C) insurance industry in the USA.

Stochastic frontier analysis is used to measure cost and revenue efficiencies of P/C insurance companies utilizing different distribution systems.

Independent agent insurers are found to be cost inefficient compared to insurers with other distribution systems, but the independent agent insurers have better revenue efficiency compared to their long counterpart, the exclusive agent insurers. This study also documents that the direct writing system provides higher cost and revenue efficiencies than other distribution systems, although their efficiencies have been deteriorating during the same time period.

Future research could examine whether the findings change by measuring efficiencies with a non‐parametric method, i.e. data envelopment analysis.

A start‐up insurer should consider a direct writing system, which is most cost and revenue efficient.

This paper investigates efficiencies of insurers by four different distribution systems and tracks efficiency changes of insurers over 12‐year periods.

Considering the “size effect” and the properties degradation of building materials on the strengthened engineering, in this paper, the technology of pasting steel plate was adopted to shear strengthen a 16 m prestressed concrete hollow slab, which had serviced 20 years in cold regions. The shear properties of shear strengthen beams are analyzed.

Shear loading test of the shear strengthened beam and the contrast beam was conducted. Then the mechanical characteristics, failure mechanism, the mechanical response and shear capacity of shear strengthened beam and contrast beam had been discussed.

The failure mode of shear strengthened beam and contrast beam was shear compression failure, and the bond failure between concrete and prestressed reinforcement happened in both of test beams. The shear strengthening method of pasting steel plate can effectively improve the mechanical response for the shear strengthened beam. Compared with the contrast beam, the cracking load and failure shear capacity for the shear strengthened beam can be effectively increased by 12.2 and 27.6%, respectively.

The research results can be a reference for the detection and evaluation of shear strengthened bridges, which are strengthened by pasting steel plate. Engineers can refer to the shear strengthening method in this paper to strengthen the existing bridge, which can guarantee the safety of shear strengthened bridges.

Plastic pollution is a widespread problem around the world. However, the problem is more severe and ever increasing in developing countries. The literature suggests that the majority of the work and the solutions that have been proposed to address plastic littering have been undertaken in developed countries. Thus, there is a need to explore the problem in developing countries to better understand the issue and to develop context-specific solutions. We explored the norms perspective using ‘The Focus Theory of Normative Conduct’, individual ethical position and place attachment factors. Interviews were conducted in Pakistan with 16 people who were recently at a beach at which there was a large amount of plastic litter. Results showed that people are influenced by the pro-littering social norms of their friends and neighbours. However, people with strong anti-littering personal norms are not influenced by pro-littering social norms. We also found that people have varying moral position, and their lack of attachment with the public place also influences their littering behaviour. Moreover, people believe that other people litter due to lack of education and awareness, lack of garbage bins and a general level of carelessness. Future research needs to focus on activating an individual's idealist moral position and an individuals' attachment with the place to enhance the activation of anti-littering personal norms which will help reduce littering behaviour. Further still, government needs to set up campaigns at public places to create awareness among people about the impact of littering, and government also needs to improve the effectiveness and efficiency of waste management. Businesses can also play a role by providing waste bins which may be used as a source of promoting their support for reducing litter.

This chapter uses the historian’s method of micro-history to rethink the significance of the Supreme Court decision Muller v. Oregon (1908). Muller is typically considered a labor law decision permitting the regulation of women’s work hours. However, this chapter argues that through particular attention to the specific context in which the labor dispute took place – the laundry industry in Portland, Oregon – the Muller decision and underlying conflict should be understood as not only about sex-based labor rights but also about how the labor of laundry specifically involved race-based discrimination. This chapter investigates the most important conflicts behind the Muller decision, namely the entangled histories of white laundresses’ labor and labor activism in Portland, as well as the labor of their competitors – Chinese laundrymen. In so doing, this chapter offers an intersectional reading of Muller that incorporates regulations on Chinese laundries and places the decision in conversation with a long line of anti-Chinese laundry legislation on the West Coast, including that at issue in Yick Wo v. Hopkins (1886).

Looking for ways to gain competitive advantage (CA) is one of the most challenging issues for today's businesses. Although previous research considered several aspects in this regard, the literature has largely overlooked the process of gaining CA via strategic intangibles, regarding business type and context. This paper aims to examine how to gain CA through strategic intangibles such as intellectual capital (IC).

Building on the concept of IC, and using data gathered from both the manufacturing/service and public/private firms, the authors tested a moderated mediation model to determine if the effect of IC on CA was conditioned on business type, competitive intensity and managerial support.

Among the factors in the relationship between IC and CA, the results discovered the role of business intelligence (BIN) and brand image (IM), as two key mediators. Furthermore, it was revealed that managerial support and competitive intensity moderate the relationship between IC, the mediators and CA. Finally, the authors provide academics and practitioners with some implications.

Previous research did not fully address the aforementioned antecedents (i.e., IC, BIN and IM) toward CA in a comprehensive model. Developing the path toward CA by focusing on the role of intangibles, the authors proposed a moderated mediation model, which has hitherto received scant attention in the field of competition.

The purpose of this study is to investigate the influence of varying concentrations of nano-SiO₂ particle doping on the structure and properties of the micro-arc oxidation (MAO) coating of 7075 aluminum alloy. This research aims to provide novel insights and methodologies for the surface treatment and protection of 7075 aluminum alloy.

The surface morphology of the MAO coating was characterized using scanning electron microscope. Energy spectrometer was used to characterize the elemental content and distribution on the surface and cross section of the MAO coating. The phase composition of the MAO coating was characterized using X-ray diffractometer. The corrosion resistance of the MAO coating was characterized using an electrochemical workstation.

The results showed that when the addition of nano-SiO₂ particles is 3 g/L, the corrosion resistance is optimal.

This study investigated the influence of different concentrations of nano-SiO₂ particles on the structure and properties of the MAO coating of 7075 aluminum alloy.