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High-entropy alloy (HEA) offers great flexibility in materials design with 3–5 principal elements and a range of unique advantages such as good microstructure stability, mechanical strength over a broad range of temperatures and corrosion resistance, etc. Welding of high entropy alloy, as a key joining method, is an important emerging area with significant potential impact to future application-oriented research and technological developments in HEAs. The selection of feasible welding processes with optimized parameters is essential to enhance the applications of HEAs. However, the structure of the welded joints varies with material systems, welding methods and parameters. A systemic understanding of the structures and properties of the weldment is directly relevant to the application of HEAs as well as managing the effect of welding on situations such as corrosion that are known to be a service life limiting factor of welded structures in conditions such as marine environments. In this paper, key recent work on welding of HEAs is reviewed in detail focusing on the research of main HEA systems when applying different welding techniques. The experimental details including sample preparation, sample size (thickness) and welding conditions reflecting energy input are summarized and key issues are highlighted. The microstructures and properties of different welding zones, in particular the fusion zone (FZ) and the heat affected zones (HAZ), formed with different welding methods are compared and presented in details and the structure-property relationships are discussed. The work shows that the weldability of HEAs varies with the HEA composition groups and the welding method employed. Arc and laser welding of AlCoCrFeNi HEAs results in lower hardness in the FZ and HAZ and reduced overall strength. Friction stir welding results in higher hardness in the FZ and achieves comparable/higher strength of the welded joints in tensile tests. The welded HEAs are capable of maintaining a reasonable proportion of the ductility. The key structure changes including element distribution, the volume fraction of face centered cubic (FCC) and body centered cubic (BCC) phase as well as reported changes in the lattice constants are summarized and analyzed. Detailed mechanisms governing the mechanical properties including the grain size-property/hardness relationship in the form of Hall–Petch (H–P) effect for both bulk and welded structure of HEAs are compared. Finally, future challenges and main areas to research are highlighted.

Taking into account X-ray diffraction, one of the well-known methods for calculating the stress-strain of crystals is Williamson-Hall (W–H). The W-H method has three models, namely (1) Uniform deformation model (UDM); (2) Uniform stress deformation model (USDM); and (3) Uniform deformation energy density model (UDEDM). The USDM and UDEDM models are directly related to the modulus of elasticity (E). Young’s modulus is a key parameter in engineering design and materials development. Young’s modulus is considered in USDM and UDEDM models, but in all previous studies, researchers used the average values of Young’s modulus or they calculated Young’s modulus only for a sharp peak of an XRD pattern or they extracted Young’s modulus from the literature. Therefore, these values are not representative of all peaks derived from X-ray diffraction; as a result, these values are not estimated with high accuracy. Nevertheless, in the current study, the W-H method is used considering the all diffracted planes of the unit cell and super cells (2 × 2 × 2) of Hydroxyapatite (HA), and a new method with the high accuracy of the W-H method in the USDM model is presented to calculate stress (σ) and strain (ε). The accounting for the planar density of atoms is the novelty of this work. Furthermore, the ultrasonic pulse-echo test is performed for the validation of the novelty assumptions.

Toxicologist George Gray, an expert in risk assessment, won approval from a Senate panel last week to lead the Environmental Protection Agency's Office of Research and Development . On the other hand, H. Dale Hall, a controversial career administrator at the US Fish and Wildlife Service, is in line to run the agency over the objections of several environmental groups that question his commitment to protecting threatened and endangered species.

Mrs Hall asks in her letter where I was during the \"dark days\" of World War Two, in which her \"loved ones\" were fighting for the survival of this country.

  When I was at boarding school in North Wales in the early 1950s close to Offa's Dyke (built to keep the Welsh out), there was a large Polish camp next to us. Pupils of the school were forbidden to have contact with the Polish refugees. They were considered to be second-class citizens.

All statements in this news release, other than statements of historical fact that address events or developments which Delta Gold or Commonwealth Silver expect to occur, constitute \"forward-looking information\". These statements relate to future events or future performance and reflect Commonwealth Silver's and Delta Gold's current expectations regarding the Transaction, the Financing, the Consolidation, and the future growth, results of operations, business prospects and opportunities of each of Commonwealth Silver and Delta Gold (and the Resulting Issuer). Forward-looking information reflects Commonwealth Silver's and Delta Gold's current internal projections, expectations or beliefs and are based on information currently available to Commonwealth Silver and Delta Gold, respectively. In some cases forward-looking information can be identified by terminology such as \"may\", \"will\", \"should\", \"expect\", \"intend\", \"plan\", \"anticipate\", \"believe\", \"estimate\", \"projects\", \"potential\", \"scheduled\", \"forecast\", \"budget\" or the negative of those terms or other comparable terminology. Assumptions upon which such forward-looking information is based include, among others, that Delta Gold and Commonwealth Silver will be able to satisfy the conditions to closing contained in the Agreement and any subsequent definitive agreement, that the Financing will be completed on terms favourable to Commonwealth Silver, that the required approvals to the Transaction and matters relating thereto will be obtained from the shareholders of each of Delta Gold and Commonwealth Silver, that all required regulatory, court and governmental approvals will be obtained on a timely basis and on terms favourable to the parties, and that the business prospects and opportunities of the Resulting Issuer, including its plans for the Commonwealth Project, the Imperial Project and other non-material mineral exploration properties, will proceed as anticipated. Many of these assumptions are based on factors and events that are not within the control of Delta Gold, Commonwealth Silver or the Resulting Issuer, and there is no assurance they will prove to be correct or accurate. Risk factors that could cause actual results to differ materially from those predicted herein include, without limitation: the speculative nature of the mineral exploration and development industry; an inability to obtain any of the approvals required to complete the Transaction; volatility in financial markets or general economic conditions; capital requirements and the need for additional financing; fluctuations in international currency markets and in the rates of exchange for the currencies of Canada and the United States; price volatility in the spot and forward markets for commodities generally and for gold and silver in particular; discrepancies between actual and estimated production, Mineral Reserves and Mineral Resources, metallurgical recoveries and/or exploration results; changes in regulations and unpredictable political or economic developments in the countries in which Delta Gold and Commonwealth Silver (and the Resulting Issuer) does or may carry on business; competition in the mineral exploration and development industry; loss of key personnel; changes in project parameters as plans continue to be refined; accidents; labour disputes; and defective title to mineral claims or property or contests over claims to mineral properties. In addition, there are risks and hazards associated with the business of mineral exploration, development and mining, including environmental hazards, industrial accidents, unusual or unexpected formations, pressures, cave-ins and flooding (and the risk of inadequate insurance or inability to obtain insurance to cover these risks), as well as the risks disclosed under the heading \"Risks and Uncertainties\" in the most recent management discussion and analysis for Delta Gold available under Delta Gold's SEDAR profile at www.sedar.com. Forward-looking information is not a guarantee of future performance and actual results and future events could differ materially from those discussed in any such forward-looking information. All of the forward-looking information contained in this news release is qualified by these cautionary statements. Although Commonwealth Silver and Delta Gold believe that the forward-looking information contained herein is based on reasonable assumptions, readers cannot be assured that actual results will be consistent with such statements. Accordingly, readers are cautioned against placing undue reliance on any of the forward-looking information contained herein.

\"This species has had a long journey,\" [H. Dale Hall] said. \"This is truly a success story.\" \"The pelican is one of the best indicators of environmental health,\" said Daniel Anderson, an ecotoxicologist at the University of California, Davis, who has studied California pelicans since 1971. \"When you see a flock of pelicans fly by, you think all's well out there. When you don't see them, then you know something's wrong.\" Little opposition is expected. \"I have no objection to delisting at this stage,\" Anderson said. \"They're probably back to at least former numbers, maybe a little bit more. They are a pretty darn adaptable species.\"

  Since 2002, the city has directed $190,100 to support local art and cultural groups. This year, the City Council continued its support and awarded grants totaling almost $40,000 to nine organizations. That's up from $35,000 last year. The program awarded $25,000 in its first year. This year, the Choral Arts Society received a $5,000 grant. That money -- along with members' dues and donations -- will be used to purchase the choir's sheet music and pay a stipend to the artistic director and orchestra conductor, [H. Cutler Hall] said. According to the agreement, the city can lease an 8.5-acre site to the foundation for $1 a year for 30 years. The center must be operating by 2012 or the city could take back the land. Plans call for a 75,000- to 95,000-square-foot arts center in Town Center, a planned commercial complex in Palm Coast between Belle Terre Parkway and Interstate 95.