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The purpose of this paper is to study the influence of Zr content on immersion and electrochemical corrosion behavior of Zr-containing Ti-based (TiZr) alloys.

The phase analysis of as-cast TχZAB alloys was carried out using X-ray diffraction. The microstructure of corrosion surfaces of the samples was observed using optical metallographic microscopy and scanning electron microscopy, equipped with energy dispersive spectroscopy.

The immersion test reveals that the corrosion is alleviated in the presence of a high amount of Zr, whereas pitting corrosion occurs when the Zr content is up to 40 Wt.%. Furthermore, the electrochemical analysis demonstrates that the corrosion resistance TiZr alloys is improved with increasing Zr content.

The TiZr alloys are promising candidates for high-end applications because of their excellent comprehensive properties. These alloys are usually used in marine or other harsh corrosive environments; therefore, it is essential to study their corrosion behavior.

This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO₂ and its radiative cooling effect on firefighting clothing without environmental pollution.

SA/SiO₂ aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple.

When the addition of SiO₂ is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO₂ aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test.

SA/SiO₂ aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling.

This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters.

SA/SiO₂ aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply.

The study aims to examine the effect of inclusions and inherent microstructure on fatigue behavior of 34Cr2Ni2Mo steel.

Fatigue behavior of 34Cr2Ni2Mo steel was investigated for up to 1E10 cycles.

Results showed that both inclusion and inherent microstructure have an influence on the crack initiation mechanism. Fatigue cracks mostly initiated from inclusions, whereas substrate-induced crack initiations were also observed. Fatigue life of inclusion-induced failures is mostly determined by the location of inclusions rather than the loading stress. The inherent microstructure seems to tolerate inclusions at a lower stress level in very high-cycle regime owing to the absence of internal inclusion-induced failure. For the substrate-induced crack initiations, high-density dislocations are found to be accumulated around the carbide particle-matrix interface, which may be the cause of crack initiation in the inherent structure due to strain localization.

The effect of inclusions and inherent microstructure on fatigue behavior of 34Cr2Ni2Mo steel up to 1E10 cycles.

Highlights

• Fatigue failure occurs even at a lifetime of 5.76E9 cycles.

• Surface inclusion induced premature failures.

• Inherent microstructure tolerates inclusions at lower stress level.

• Internal carbides promote substrate-induced crack initiations.

Fatigue failure occurs even at a lifetime of 5.76E9 cycles.

Surface inclusion induced premature failures.

Inherent microstructure tolerates inclusions at lower stress level.

Internal carbides promote substrate-induced crack initiations.

This paper aims to study the oxidation kinetics of the nanocrystalline Al ultrathin films. The influence of structure and composition evolution during thermal oxidation will be observed. The reason for the change in the oxidation activation energy on increasing the oxidation temperature will be discussed.

Al thin films are deposited on the silicon wafers as substrates by vacuumed thermal evaporation under the base pressure of 2 × 10⁻⁴ Pa, where the substrates are not heated. A crystalline quartz sensor is used to monitor the film thickness. The film thickness varies in the range from 30 to 100 nm. To keep the silicon substrate from oxidation during thermal oxidation of the Al film, a 50-nm gold film was deposited on the back side of silicon substrate. Isothermal oxidation studies of the Al film were carried out in air to assess the oxidation kinetics at 400-600°C.

The activation energy is positive and low for the low temperature oxidation, but it becomes apparently negative at higher temperatures. The oxide grains are nano-sized, and γ-Al₂O₃ crystals are formed at above 500°C. In light of the model by Davies, the grain boundary diffusion is believed to be the reason for the logarithmic oxidation rate rule. The negative activation energy at higher temperatures is apparent, which comes from the decline of diffusion paths due to the formation of the γ-Al₂O₃ crystals.

It is found that the oxidation kinetics of nanocrystalline Al thin films in air at 400-600°C follows the logarithmic law, and this logarithmic oxidation rate law is related to the grain boundary diffusion. The negative activation energies in the higher temperature range can be attributed to the formation of γ-Al₂O₃ crystal.

In modern urban governance, rescue materials storage points (RMSP) are a vital role to be considered in responding to public emergencies and improving a city's emergency management. This study analyzes the siting of community-centered relief supply facilities.

Combining grey relational analysis, complex network and relative entropy, a new multi criteria method is proposed. It pays more attention to the needs of the community, taking into account the use of community hospitals, fire centers and neighborhood offices to establish small RMSP.

The research results firstly found suitable areas for RMSP site selection, including Hanyang, Qiaokou, Jiangan and Wuchang. The top 10 nodes in each region are found as the location of emergency facilities, and the network parameters are higher than ordinary nodes in traffic networks. The proposed method was applied in Wuhan, China and the method was verified by us-ing a complex network model combined with multi-criteria decision-making for emergency facility location.

This method solves the problem of how to choose the optimal solution and reduces the difficulty for decision makers. This method will help emergency managers to locate and plan RMSP more simply, especially in improving emergency siting modeling techniques and additionally in providing a reference for future research.

The method proposed in this study is beneficial to improve the decision-making ability of urban emergency departments. Using complex networks and comprehensive evaluation techniques, RMSP is incorporated into the urban community emergency network as a critical rescue force. More importantly, the findings highlight a new direction for further research on urban emergency facilities site selection based on a combination of sound theoretical basis as well as empirical evidence gained from real life case-based analysis.

1. Material reserve points are incorporated into the emergency supply network to maintain the advantage of quantity.

2. Build emergency site selection facilities centered on urban communities.

3. Use a complex network model to select the location of emergency supplies storage sites.

Material reserve points are incorporated into the emergency supply network to maintain the advantage of quantity.

Build emergency site selection facilities centered on urban communities.

Use a complex network model to select the location of emergency supplies storage sites.

Special education in China has lagged behind regular education for many years, however, the past few decades, the government has made considerable efforts to develop and improve the special education system. While the citizens of China have had a generic moral interest in disability since ancient times, the development of special education schools did not occur until American and European missionaries started schools for the visually and hearing impaired in the 19th century. The next major influence in the development of the special education system occurred with China’s Cultural Revolution in 1978. Interestingly, there is not any exclusive legislation on special education but in the 1980s, the government started Learning in Regular Classrooms (LRC), which is China’s version of inclusion. LRC has progressed rapidly the past two decades; however, the quality of instruction is low due to a lack of specialists, a shortage of personnel, inadequate funding, and limited technology as well as other barriers that are delineated in the chapter. The chapter emphasizes the government’s recent efforts in in-service teacher training, the preparation of preservice teachers, working with families, developing community rehabilitation training programs, and implementing evidence-based practices. Special education in China today is at a good place but it has quite a way from the ideal situation.

This study aims to research the influence of non-probabilistic design variables on interval robust optimization of electric multiple units (EMU) brake module, therefore obtain the reasonable of design variables of the EMU brake module.

A robust optimization model of the EMU brake module based on interval analysis is established. This model also considers the dimension tolerance of design variables, and it uses symmetric tolerance to describe the uncertainty of design variables. The interval order relation and possibility degree of interval number are employed to deal with the uncertainty of objective function and constraint condition, respectively. On this basis, a multiobjective robust optimization model in view of interval analysis is established and applied to the robust optimization of the EMU brake module.

Compared with the traditional method and the method proposed in the reference, the maximum stress fluctuation of the EMU brake module structure is smaller after using the method proposed in this paper, which indicates that the robustness of the maximum stress of the structure has been improved. In addition, the weight and strength of the structure meet the design requirements. It shows that this method and model introduced in this research have certain feasibility.

This study is the first attempt to apply the robust optimization model based on interval analysis to the optimization of EMU structure and obtain the optimal solution set that meets the design requirements. Therefore, this study provides an idea for nonprobabilistic robust optimization of the EMU structure.

The China threat is the first and most obvious answer when it comes to the question of threat perception in Taiwan, but the issue encompasses much more. The ruling elite for years considered the subject population a threat, for example, and even the nature and severity of the China threat varies greatly depending on an individual’s identification. How do those who identify as Taiwanese see the consequences of an attack from China? There is a very different threat perception among the Taiwanese population, who view annexation by China in much the same way as their Mainlander counterparts would see annexation by Japan, for example. Persons self-identifying as Taiwanese do not view themselves as being culturally the same as the people across the Taiwan Strait, having grown apart from them (in a cultural sense) over the past 120 years that they have been separated. Moreover, after Taiwan’s long history of being colonized by one alien power after another – from the Dutch and Spanish, to Koxinga, and then the Manchu dynasty; by the Japanese; and finally by the KMT (for being colonized is how many Taiwanese perceive the ROC period) – finally the inhabitants of the island have the opportunity to chart their own future, and enjoy a newfound sovereignty and identity separate from that of any colonizing power: thus the prospect of being colonized by China is anathema, and therefore a much greater existential threat for them than for Mainlanders.

This paper discusses some aspects of the performing arts of the Tibetans and attempts to analyze how they have fared within the context of an extremely large and modernizing state, where since the late 1970s modernization has been accompanied by a contrary revival of traditions. It argues that performing arts traditions remain powerful among the Tibetans and takes issue with the frequently heard notion that Tibetan culture is being destroyed. It contends, however, that the acceleration of modernization in the coming decades could weaken the tradition in Tibetan culture by affecting its link with the society which feeds it. But what is likely to develop is a changed Tibetan culture, with more place given to those features we know as modernity. On the other hand, the traditions are most unlikely to die out in the foreseeable future. The topical focus of the article is on the performing arts, especially the related forms of drama, balladry and dance. The period of focus is that since the early 1980s, and especially the 1990s.