Copper shell

For copper ions, the account of the electron correlation at the MP2 level decreases the charges about 1.5 times or on 32 % for the Cul and on 36.4% for the Cu2. The change of copper charges for the transition in calculation methods ROHF —> UHF is not such essential as for the transition UHF — MP2. The account ofthe electron correlation causes also the essential change of the occupation orbital numbers of the 4s and 3d copper shells. The 4s copper electrons are involved in the covalent bonding with the 2p oxygen electrons. 

Henkin McGill (Ref 15) give the following expl times for 25 mg of Tetryl in copper shells of 0.635mm diam submerged into a hot Wood s metal bath ... 

Another underground disposal site project is in Finland at the Olkiluoto Nuclear Power Plant. The proposed waste site will store spent fuel rods in iron canisters sealed in copper shells to resist corrosion. The canisters will be placed in holes surrounded by clay far below ground. The project is slated for completion in 2020. 

This is an example of a conservative assumption permissible in such a performance assessment model. In reality, a narrow aperture failure in the copper shell would allow only a very slow entry of water into the container. 

To compare the performance of K2DNABT with that of lead azide, 40 mg of K2DNBT was loaded in a small aluminum holder and 1 g of RDX was pressed in a standard detonator copper shell. This was initiated by an electrical igniter. The... 

Although the copper skin was in good shape, the interior of the copper shell had layers of coal tar, aluminum, and lead that needed to be cleaned off. The restoration project was completed in 1986, in time for the statue s centennial celebration. 

The uranium oxide was held in most cases in steel shells 6.8 by 10 cm thick, surrounded by shields to absorb thermal neutrons. No difference was found if copper shells were used in place of the steel. The thermal neutron shields were of two types one a mixture of CdS04 and AI2O3 such that there was 0.49 g/cm of Cd around the sphere, and the other B4C and AI2O3, sufficient to place 0.13 g/cm of B around the sphere. Above 700°C, in the CO atmosphere generated by diffusion of air into the furnace, the CdS04 decomposed, and CdS and Cd boiled off. Therefore, a chemical analysis of the shell was made after use, showing that some of the experiments were done with less Cd around the uranium than were others. To partially remedy this trouble, CdSiOs shells were prepared, but they also partly decomposed to Cd which evaporated. 

A 2-in. copper shell filled with UO2, not surrounded with Cd, showed about 15 percent less absorption at 700°C than at 20°C. This is due to the smaller effectiveness of the thermal neutrons at the higher temperature since the cross section decreases as l/z>. 

A popular classroom demonstration consists of filing notches into a new permy and soaking the penny in hydrochloric acid overnight. Since new pennies are made of zinc coated with copper, and since hydrochloric acid dissolves zinc and not copper, the inside of the penny is dissolved by the acid, while the outer copper shell remains. Suppose the penny contains 2.5 g of zinc and is soaked in 20.0 mL of 6.0 M HCl. Calculate the concentration of the HQ solution after all of the zinc has dissolved. Hint The Zn from the penny is oxidized to Zn. ... 

Yu Seunggun, Lee Jang-Woo, Han Tae Hee, et al. Copper shell networks in polymer composites for efficient thermal conduction. ACS Appl. Mater. Interf. 5 no. 22 (2013) 11618-11622. 

The original design and structure of the Statue of Liberty, built about 100 years ago, took into accoimt the need to avoid using different metals in direct contact with each other. However, the salt sea spray penetrated the structure and corroded the iron frame which supported the outer copper shell. Chloride ions catalyzed the corrosion of iron. The use of brass in a steam line valve resulted in corrosion and the formation of a green solid product. The architect was apparently unaware of the standard practice to use amines such as morpholine as a corrosion inhibitor for steam lines. Amines react with copper in the brass at high temperatures in the presence of oxygen to form copper-amine complexes similar to the dark blue copper ammonium complex, Cu(NH3)J. ... 

Slightly different results were obtained with confined samples of tetryl. The explosion times for 25 milligrams of tetryl in copper shells of 0.635 millimeter diameter submerged in a hot woods metal bath are shown in table 8-29. 

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