A light hull (casing in British usage) of a submarine is the outer non-watertight hull which provides a hydrodynamically efficient shape. The pressure hull is the inner hull of a submarine; this holds the difference between outside and inside pressure.
Modern submarines are usually cigar-shaped. This design, already visible on very early submarines is called a "teardrop hull", and was patterned after the bodies of whales. It significantly reduces the hydrodynamic drag on the sub when submerged, but decreases the sea-keeping capabilities and increases the drag while surfaced.
The concept of an outer hydrodynamically streamlined light hull separated from the inner pressure hull was first introduced in the early pioneering submarine Ictineo I designed by the Catalan inventor Narcís Monturiol i Estarriol in 1859. However, when military submarines entered service in the early 1900s, the limitations of their propulsion systems forced them to operate on the surface most of the time; their hull designs were a compromise, with the outer hulls resembling a ship, allowing for good surface navigation, and a relatively streamlined superstructure to minimize drag under water. Because of the slow submerged speeds of these submarines, usually well below 10 knots (19km/h), the increased drag for underwater travel by the conventional ship like outer hull was considered acceptable. Only late in World War II, when technology enhancements allowed faster and longer submerged operations and increased surveillance by enemy aircraft forced submarines to spend most of their times below the surface, did hull designs become teardrop shaped again, to reduce drag and noise. On modern military submarines the outer hull (and sometimes also the propeller) is covered with a thick layer of special sound-absorbing rubber, or anechoic plating, to make the submarine more difficult to detect by active and passive SONAR.
The town of Hull was founded late in the 12th century. The monks of Meaux Abbey needed a port where the wool from their estates could be exported. They chose a place at the junction of the rivers Hull and Humber to build a quay.
The exact year the town was founded is not known but it was first mentioned in 1193.
Renamed Kings-town upon Hull by King Edward I in 1299, Hull has been a market town, military supply port, trading hub, fishing and whaling centre, and industrial metropolis.
Hull was an early theatre of battle in the English Civil Wars. Its 18th-century Member of Parliament, William Wilberforce, played a key role in the abolition of the slave trade in Britain.
Recycling is the process of converting waste materials into reusable objects to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, energy usage, air pollution (from incineration) and water pollution (from landfilling) by decreasing the need for "conventional" waste disposal and lowering greenhouse gas emissions compared to plastic production. Recycling is a key component of modern waste reduction and is the third component of the "Reduce, Reuse and Recycle" waste hierarchy.
There are some ISO standards related to recycling such as ISO 15270:2008 for plastics waste and ISO 14001:2004 for environmental management control of recycling practice.
Recyclable materials include many kinds of glass, paper, metal, plastic, tires, textiles and electronics. The composting or other reuse of biodegradable waste—such as food or garden waste—is also considered recycling. Materials to be recycled are either brought to a collection centre or picked up from the curbside, then sorted, cleaned and reprocessed into new materials destined for manufacturing.
A nutrient cycle (or ecological recycling) is the movement and exchange of organic and inorganic matter back into the production of living matter. The process is regulated by food web pathways that decompose matter into mineral nutrients. Nutrient cycles occur within ecosystems. Ecosystems are interconnected systems where matter and energy flows and is exchanged as organisms feed, digest, and migrate about. Minerals and nutrients accumulate in varied densities and uneven configurations across the planet. Ecosystems recycle locally, converting mineral nutrients into the production of biomass, and on a larger scale they participate in a global system of inputs and outputs where matter is exchanged and transported through a larger system of biogeochemical cycles.
Recycling (technological) A human industrial process of shunting discarded technological artifacts into an industrial repository system that dissipates energy and employs people to manufacture and redistribute new artifacts using the old materials.
A Turkish shipyard had previously bought the hull, and had planned to dismantle it ... This has led to the recycling ... After it was stripped of many of its systems, in 2021, the ship's hull was sold to a Turkish company Sok Shipping, accredited and certified to carry out safe recycling....
“The area for the final disposal of the hull was selected based on studies ...Brazil in a previous statement attempted to place blame for the situation on Turkey for not permitting the green recycling to proceed and the scrapper for failing to contract for repairs to the hull....
The hull of the Sao Paulo was sunk in Brazilian jurisdictional ... After the carrier was decommissioned, Turkish marine recycling company Sök Denizcilik Tic Sti bought the hull for $10.5 million, but had to tow it back across the Atlantic when Turkey barred entry to its shipyard....
Its goal was to recycle the vessel, disposing of any waste responsibly while making a profit salvaging and selling the tons of nontoxic metals it contained ... Months passed, and as minor damage started appearing in the hull, MSKMaritime Services & Trading, a partner in the recycling project with Sok Denizcilik, grew desperate....
To comply with international treaties, including the Basel Convention restricting the export of toxic waste, Puckett says the navy must tow the São Paulo into a naval base, repair the damage to the hull, and then offer the recycling contract to new shipyards in Europe, which can safely remove the asbestos before dismantling the ship....
The InnovationYachts shipyard has engineered and manufactured the world’s first completely recyclable and sustainable catamaran from composite materials for series production. The IY LBV35 is the first model in a new series of sustainable and completely recyclable boats and is electrically propelled by solar energy and a hydrogenator....