Was Crocodile stronger at Marineford? Or was he holding back in Alabasta?

 During the Alabasta arc, Crocodile displayed a level of power that was initially considered overwhelming by the Straw Hat Pirates. He possessed the Logia-type Devil Fruit called the Suna Suna no Mi (Sand-Sand Fruit), which granted him the ability to control and transform into sand. He had a reputation as a Shichibukai and controlled the desert kingdom of Alabasta from the shadows. His strength was showcased through his battles with Luffy and others. At Marineford, Crocodile was present as part of the war that took place at Marine Headquarters. While he did participate in the battle, he didn't display the same level of dominance as some other powerful characters present. This has led fans to speculate that he might not have been as strong as initially portrayed in Alabasta. It's important to note that power scaling and character abilities can be subject to interpretation and development by the author. Oda often keeps details deliberately open-ended to keep the story intriguing.

What are some uses of depleted uranium (DU)? What is its importance in nuclear energy and other fields?

 Depleted uranium (DU) is a byproduct of the process of enriching natural uranium, which is used as fuel in nuclear power plants and in the production of nuclear weapons. DU is less radioactive than natural uranium and has lower levels of certain isotopes, such as U-235, which is used in nuclear fuel and weapons.

DU has a number of uses, including:

Industrial applications: DU is used in some industrial applications, such as the production of radiation shielding and ballast weights.

Military uses: DU has been used in some military applications, such as armor-piercing bullets and missiles. It is also used in some armored vehicles and tanks for additional protection against armor-piercing weapons.

Medical uses: DU has been used in some medical applications, such as in the production of radiation shielding for medical equipment and in the treatment of some types of cancer.

Overall, DU is an important byproduct of the nuclear fuel production process and has a variety of uses, including industrial, military, and medical applications. However, its use in some military applications, such as armor-piercing bullets and missiles, has raised concerns about its potential health and environmental impacts.