Mechanical Properties and Deformation Mechanisms of Heterostructured High-Entropy and Medium-Entropy Alloys: A Review

Recently, heterostructured (HS) materials, consisting of hard and soft zones with dramatically different strengths, have been developed and received extensive attention because they have been reported to exhibit superior mechanical properties over those predicted by the rule of mixtures. Due to the accumulation of geometrically necessary dislocations during plastic deformation, a back stress is developed in the soft zones to increase the yield strength of HS materials, which also induce forward stress in the hard zones, and a global hetero-deformation induced (HDI) hardening to retain ductility. High-entropy alloys (HEAs) and medium-entropy alloys (MEAs) or multicomponent alloys usually contain three or more principal elements in near-equal atomic ratios and have been widely studied in the world. This review paper first introduces concepts of HS materials and HEAs/MEAs, respectively, and then reviewed emphatically the mechanical properties and deformation mechanisms of HS HEAs/MEAs. Finally, we discuss the prospect for industrial applications of the HS HEAs and MEAs.

Meteorological Factors and the COVID-19 Pandemic: The Backdrop of Pakistan

Coronavirus victims have been confirmed all around the world and millions of people are being put into self-isolation. In this backdrop, a superior appreciation of the effective parameters in epidemic spreading can cause a cogent assessment toward COVID-19. In this vein, the consequences of weather indicators on the spread of COVID-19 can play an instrumental role in the current coronavirus situation enveloping the world. These elements entail time, maximum and minimum temperature, humidity, wind speed, and rainfall. By such an incorporation, their consequent effects on coronavirus in Pakistan are explored. In the current study, principal elements are considered including the number of infected patients with coronavirus in Pakistan. The autoregressive distribution lag (ARDL) approach is used to analyze the effects and relationships of variables with the COVID-19 expansion rate extracting data from April 1, 2020 to April 30, 2021. The results revealed that maximum and minimum temperature, humidity, wind speed, and rainfall had a significant positive correlation with total and confirmed cases of COVID-19. Lastly, this brief communication attempts to clarify the outbreak of coronavirus in the region.

Лексико-семантический анализ топонимии чувашского села Большое Алдаркино Борского района Самарской области и его окрестностей

The article deals with the inventory of toponyms of the village of Bolshoe Aldarkino, Borskii district, Samara region, introduced and analyzed for the first time by the present author. The village was founded by the descendants of Virjal Chuvash in 1767. The research database has been formed by the evidence on the toponymics of the village and its surrounding area collected by the author from locals and local historians during his field trip in 2018. Also, for a comparative analysis of the toponyms under study, he has made use of the relevant material collected by him in other Chuvash villages of the Samara Volga region in the period between 2015 and 2019; these are first of all the villages in Borskii, Pokhvistnevskii, and Isaklinskii districts. As a result, it was possible to identify the principal elements of the toponymic items of the Chuvash idiolect of Bolshoe Aldarkino, their particular forms and semantics. To illustrate, such terms as var (ravine) or oshken´(street) have peculiarities in their structure, forms, and semantics, which make them distinctly characteristic of this particular Chuvash dialect in contrast to those spoken in the neighboring Chuvash villages. Most of the names presented in the article are etymologized from the Chuvash and Russian languages, a number of toponyms are currently de-etymologized, but there are no grounds to refer them to any other language. There is no substrate layer in the toponymic space under study. Some geographical names display the features of the Virjal dialect of the Chuvash language, including Odar, Vyras Oshken, Tikhon Oshken, etc. A few geographical items of the toponymic space of Bolshoe Aldarkino have convincing lexical and semantic parallels in the toponymic spaces of other Chuvash villages in the region, as well as of other settlements of Chuvash speakers.

Core Elements towards Circularity: Evidence from the European Countries

In this paper, the authors identified key elements important for circularity. The primary goal of circularity is to eliminate waste and prove the constant use of resources. In the paper, we classified studies according to circular approaches and stated which of them get the highest attention. Further, we identified the principal elements, grouped them into four categories important for circularity, and presented scientific works dedicated to each of the above-mentioned categories. Further on, several core elements from the first category were investigated, aiming to connect different waste streams and provide a regression model. Finally, the methodological part reviewed the correlation between various types of waste and their recycling and selected suitable ones for developing a new panel regression model. The empirical research was delivered for the 27 European Union countries during the period between 2000 and 2019. We indicate that the recycling rate of municipal waste impacts the increase of recycling biowaste the same calendar year. The increase of recycling of municipal waste by one per cent means the increase of the recycling of biowaste by 0.6 per cent.

Novel High-Entropy Aluminide-Silicide Alloy

Novel high-entropy (multi-principal elements) alloy based on Fe-Al-Si-Ni-Ti in equimolar proportions has been developed. The alloy powder obtained by mechanical alloying is composed of orthorhombic FeTiSi phase with the admixture of B2 FeAl. During spark plasma sintering of this powder, the FeSi phase is formed and the amount of FeAl phase increases at the expense of the FeTiSi phase. The material is characterized by a high compressive strength (approx. 1500 MPa) at room temperature, being brittle. At 800 °C, the alloy is plastically deformable, having a yield strength of 459 MPa. The wear resistance of the material is very good, comparable to the tool steel. During the wear test, the spallation of the FeSi particles from the wear track was observed locally.

Propellant Stimulation and Hydraulic Fracturing

The Propellant Stimulation is applied to increase the permeability of rocks; a certain quantity of explosive material is donated at the bottom of the well opposite the producing layer, which causes many cracks in the near well area. A good Propellant Stimulation process must consider the explosive material quality and quantity, and the explosion should be prevented from vertically spread so all its energy will be used to crack the rocks. The first part of this chapter explains all the above in addition to the directed explosions and its calculation in an easy way. In the second part, I explained the Hydraulic Fracturing of the reservoir rocks in details, from principal elements of the process passing through cracking fluids, proppants, preparing the wells and ending with evaluating the effectiveness and discussing the methods of hydraulic fracturing. Hydraulic fracturing is the process of pumping fluid into a wellbore at an injection rate that is too high for the formation to accept without breaking. During injection the resistance to flow in the formation increases, the pressure in the wellbore increases to a value called the break-down pressure, that is the sum of the in-situ compressive stress and the strength of the formation. Once the formation “breaks down,” a fracture is formed, and the injected fluid flows through it.

14. False representations

This chapter examines the protection provided by tort law against false representations which cause the claimant to suffer some kind of financial loss (which is why they frequently are seen as falling within the category of economic torts). The chapter discusses the principal elements of three different types of false representation case, these being: deceit (based on an inducement by the defendant that the claimant rely on the statement even though the defendant was at least reckless as to its truth), passing off (based on deception of the claimant’s customers), and malicious falsehood (usually based on disparagement of the claimant’s goods).

The Acoustics of the Benevento Roman Theatre

During the Imperial Roman period, thousands of theatres were built. The theatres have three principal elements: the scene building (actor position), the orchestra and the cavea (spectator seating). The theatres were built without a roof, so they were open-air spaces. The theatres were abandoned afterward the barbarian invasions, and during the Middle Ages, homes were built inside the cavea. The theatres were rediscovered during the Renaissance period. Today, ancient theatres are the center of cultural events and are used for various kinds of shows. This work discussed the acoustics of the Roman theatre of Benevento, which was built during the Imperial Age. The theatre was destroyed after the barbaric invasion and it was rebuilt in the first half of the 1900s. The theatre was opened in 1957, and today it is the center of social and cultural activities. Acoustic measurements were carried out according to ISO 3382 standard, placing an omnidirectional sound source on the scene building and in the orchestra, with the measurement microphones along three directions in the cavea. The acoustic characteristics in various seating areas of the cavea were evaluated. Therefore, it possible to understand in which sectors of the theatre the acoustic characteristics are optimal for different types of theatrical performances.

Anti-inflammatory Properties of Fangji Huangqi Tang: Discovery Based on Network Pharmacology, Molecular Docking and Arrowsmith Tools

Fangji Huangqi Tang (FHT) is a classical formula widely used in Chinese clinical practice. In this study, a creative application of FHT for inflammation has been identified by network pharmacology-based framework. Specifically, a total of 17 bioactive compounds including 42 potential targets of FHT, and 205 related targets involved in inflammation were retrieved from mainstream databases and subjected to network analysis. 13 intersection targets indicated the principal elements linked to inflammation therapy. Top terms of Gene Ontology (GO) analysis were identified, while 7 related signaling pathways were revealed by Kyoto Encyclopedia of Genes and Genomes (KEGG) results. Subsequently, Calycosin-PTGS2 with tight binding affinity (BA) was manifested by molecular docking as the critical compound-target couple. Meaningful links between Calycosin and inflammation were implied through Arrowsmith, which overlapped with the findings in enrichment analysis, such as MAPK, NF-κB that could be regulators of PTGS2. In summary, the present study explored the potential targets and signaling pathways of FHT against inflammation, which may help to illustrate the mechanisms responsible for the action of FHT and provide a better understanding of its anti-inflammatory effects.

Keeping ‘Development’ in a Multilateral Framework on Investment Facilitation for Development

In December 2019, World Trade Organization (WTO) Members agreed that the Structured Discussions on Investment Facilitation for Development would move into a negotiating mode, previously set to begin in March 2020. Their goal is to have a concrete outcome by the WTO’s 2021 Ministerial Conference. These negotiations are an important step towards creating a multilateral framework on a specific, technical area of foreign investment – investment facilitation. This paper seeks to do two things: (1) to provide a comprehensive analysis of a potential framework by chronicling the genesis of the idea for such a framework and the discussions, discussing competing views on an investment facilitation framework and outlining the principal elements a framework; and (2) to argue that a framework should include provisions focused on facilitating sustainable investment for sustainable development. To that end, it advances suggestions for promoting sustainable investment and introduces a provision, the Recognized Sustainable Investor, that could be included in the framework to incentivize international investors to invest sustainably.