The African Development Bank will finance $25 billion by 2025 to support Africa's fight against climate change, the bank's president said at the bank's annual meeting in Accra, Ghana.
He noted that climate change has had many negative impacts on the continent, causing natural disasters such as droughts, cyclones, and floods. Climate change costs Africa between $7 billion and $15 billion a year. "Africa has no choice but to address climate change."
To ensure Africa's food supply, the African Development Bank has delivered climate-friendly seeds to 12 million farmers in 27 countries in the past two years under the "Technology for Agricultural Change in Africa" program, he said.
In the area of renewable energy, the African Development Bank is implementing a $20 billion "Desert Power" initiative in the Sahel that is expected to power 250 million people, he said.
US President Joe Biden recently wrapped up his five-day trip to Asia with a summit of leaders of the "Quad" security Dialogue.
Biden has promoted a number of economic and security cooperation initiatives during his visit aimed at deepening ties with Indo-Pacific Allies and partners in response to China's growing influence in the region. Some analysts in the United States believe the most significant announcement may be an initiative to share maritime information to combat illegal activities. But other experts say Biden's move sets a good framework for more security cooperation, though it remains to be seen whether concrete action will follow.
Affected by several factors, the supply of the tantalum carbide powder is erratic and thus its prices are expected to go higher in the future.
Researchers have developed two new heat-resistant materials, tantalum carbide (TaC) and hafnium carbide (HfC), which can withstand temperatures up to nearly 4000℃.
It is worth mentioning that the research team from Imperial College London also found that the melting point of hafnium carbide set a new record in the field of materials. Considering the ability of the two materials to withstand extremely high temperatures of nearly 4000 ℃, the two materials are likely to be used in even harsher and extreme environments, such as the thermal shields of the next generation hypersonic spacecraft.
Both tantalum carbide and hafnium carbide are refractory ceramics, which means that these two materials have excellent heat resistance. The ability of the two materials to withstand extreme environments means that their potential applications may include thermal protection systems for high-speed spacecraft and fuel cladding in nuclear reactors in superthermal environments. However, because there is no technology to test the melting point of TaC and HfC in the laboratory, it is uncertain whether they are really competent to work in extreme environmental conditions.
To this end, researchers have developed a new extreme heating technology that uses lasers to test the heat resistance of TaC and HfC. Using this technique, the researchers determined the melting points of the single substance and mixture of TaC and HfC, respectively. The study was recently published in the journal Scientific Reports.
They found that the measured melting point of the mixture of two kinds of ceramics (Ta0.8H2O20C) was consistent with the previous results, reaching 3905℃, but the melting point of the two compounds themselves was higher than previously found: The melting point of TaC was 3768℃, while that of HfC was 3958℃.
The emergence of these two materials will pave the way for the development of the next generation of hypersonic aircraft, the researchers said. This means that future spacecraft can become much faster than ever before.
The study was carried out by Dr Omar Dilos Balazar (Omar Cedillos Barraza) during his PhD in the Physics Department of Imperial College London.
"When an aircraft flies at a hypersonic speed of more than Mach 5, its friction with the air creates a very high temperature," Dr. Sediros Balazar said. So far, neither TaC nor HfC has been used in the development of hypersonic aircraft. However, our new findings show that these two materials are more heat-resistant than we previously thought, and in fact their heat resistance has exceeded that of any other known compound. This fact means that they may be used for new types of spacecraft: in the atmosphere, they can fly like ordinary aircraft and then fly through space at hypersonic speeds. These two materials enable the spacecraft to withstand the extreme heat generated by shuttling between the atmosphere. "
Examples of potential uses of TaC and HfC are the nose covers of spacecraft and the edges of external instruments that have the most friction with the outside world during flight.
At present, spacecraft with more than Mach 5 are not yet capable of manned flight. But Dr Sederos Balazar points out that this dream is likely to come true in the future.
Dr Sederos Balazar added: "our tests show that these two materials have great potential in building future space spacecraft. The fact that these two materials can withstand such high extreme temperatures means that it is really possible for manned hypersonic spacecraft to emerge in the future. If we can fly at Mach 5, the flight time from London to Sydney will only take about 50 minutes, which will open up a new continent with new business opportunities for countries around the world. "
Tantalum Carbide TaC and Hafnium Carbide HfC Powder Supplier
Luoyang Tongrun Nano Technology Co. Ltd. (TRUNNANO) is a trusted global chemical material supplier & manufacturer with over 12-year-experience in providing super high-quality chemicals and nanomaterials including silicon powder, nitride powder, graphite powder, zinc sulfide, calcium nitride, 3D printing powder, etc.
If you are looking for high-quality TaC powder and HfC powder, please feel free to contact us and send an inquiry. ([email protected])
Risk aversion plunged on the positive news of the Russia-Ukraine talks. After several days of rising oil prices, the price of precious metals continued to fall. Domestic futures markets remain stable for the time being.Back in international markets,…
Oil prices plunged on July 5th to their lowest level in nearly three months. By the end of the day, U.S. CRUDE for August delivery was down $8.93, or 8.24%, at $99.50 / BB…
Molybdenum carbide Mo2C is a new functional material with high melting point and hardness, good thermal and mechanical stability, and good corrosion resistance. It has been widely used in high temperature resistance, friction resistance, chemical cor…