secondary cell

Examples of secondary cell in the following topics:

• Other Rechargeable Batteries

  • A rechargeable battery is a type of electrical battery that is comprised of one or more electrochemical cells.
  • It is known as a secondary cell because its electrochemical reactions are electrically reversible.
  • The electrolyte may serve as a simple buffer for internal ion flow between the electrodes, as in lithium-ion and nickel-cadmium cells, or it may be an active participant in the electrochemical reaction, as in lead-acid cells.
  • The negative electrode of a conventional lithium-ion cell is made from carbon.
  • Lithium-ion polymer (LiPo) batteries are usually composed of several identical secondary cells in parallel to increase the discharge-current capability.

• The Primary Structure of DNA

  • It should be noted that single celled organisms like bacteria do not have a well-defined nucleus.
  • Isomeric 3'-monophospate nucleotides are also known, and both isomers are found in cells.
  • Furthermore, accurate copies of the DNA code must be created as cells divide, with the replicated DNA molecules passed on to subsequent cell generations, as well as to progeny of the organism.
  • The nature of this DNA organization, or secondary structure, will be discussed in a later section.
  • The high molecular weight nucleic acid, DNA, is found chiefly in the nuclei of complex cells, known as eucaryotic cells, or in the nucleoid regions of procaryotic cells, such as bacteria.

• Secondary & Tertiary Structure of Large Peptides and Proteins

  • The alpha helix is the most stable of these, accounting for a third of the secondary structure found in most globular (non-fibrous) proteins.
  • Turns reverse the direction of the peptide chain, and are considered to be a third common secondary structure motif.
  • A 170 pound human has about a kilogram of hemoglobin distributed among some five billion red blood cells.
  • In animals, hemoglobin transports oxygen from the lungs or gills to the rest of the body, where it releases the oxygen for cell use.
  • The virus makes certain proteins that need to be cleaved or cut, in order to transform into functional proteins that enable the virus to infect new cells.

• The Secondary & Tertiary Structures of DNA

  • In the early 1950's the primary structure of DNA was well established, but a firm understanding of its secondary structure was lacking.
  • After many trials and modifications, Watson and Crick conceived an ingenious double helix model for the secondary structure of DNA.
  • As depicted in the following drawing, the DNA of a cell is tightly packed into chromosomes.
  • When you consider that a human cell has roughly 109 base pairs in its DNA, and may divide into identical daughter cells in 14 to 24 hours, the efficiency of DNA replication must be extraordinary.
  • The procedure described above will replicate about 50 nucleotides per second, so there must be many thousand such replication sites in action during cell division.

• The Hydrogen Bomb

  • After this, the secondary explosive is compressed by X-rays coming from the nuclear fission of the primary explosive.
  • This process is called the "radiation implosion" of the secondary explosive.
  • Finally, the secondary explosive is heated, after cold compression, by a second fission explosion that occurs inside the secondary explosive.
  • Radiation from a primary fission bomb compresses a secondary section containing both fission and fusion fuel.
  • The compressed secondary is heated from within by a second fission explosion.

• RNA and Protein Synthesis

  • Because these macromolecules have diverse primary, secondary and tertiary structures that equip them to carry out the numerous functions necessary to maintain a living organism.
  • The cell then synthesizes the protein, using the mRNA as a template.
  • This cloverleaf secondary structure is further wrapped into an "L-shaped" assembly, having the amino acid at the end of one arm, and a characteristic anti-codon region at the other end.
  • A cell's protein synthesis takes place in organelles called ribosomes.
  • The bacterial cell wall is a cross-linked glycan polymer that surrounds bacterial cells, dictates their cell shape, and prevents them from breaking due to environmental changes in osmotic pressure.

• Extractive Metallurgy

  • Tailings of a previous process may be used as a feed in another process to extract a secondary product from the original ore.
  • Electrometallurgy involves metallurgical processes that take place in some form of electrolytic cell.
  • Fused salt electrolysis is another electrometallurgical process whereby the valuable metal is dissolved into a molten salt, which acts as the electrolyte, and the valuable metal collects on the cathode of the cell.

• Electrochemical Cell Notation

  • Cell notation is shorthand that expresses a certain reaction in an electrochemical cell.
  • Cell notations are a shorthand description of voltaic or galvanic (spontaneous) cells.
  • The anode half-cell is described first; the cathode half-cell follows.
  • Using these rules, the notation for the cell we put together is:
  • A typical arrangement of half-cells linked to form a galvanic cell.

• Dry Cell Battery

  • The dry cell is one of many general types of electrochemical cells.
  • Unlike a wet cell, a dry cell can operate in any orientation without spilling, as it contains no free liquid.
  • A common dry-cell battery is the zinc-carbon battery, which uses a cell that is sometimes called the Leclanché cell.
  • Another example of a dry-cell battery is the alkaline battery.
  • An illustration of a zinc-carbon dry cell.

• Fuel Cells

  • William Grove developed the first crude fuel cells in 1839.
  • Fuel cells are classified by the electrolyte they use, which is the main difference among the various types of fuel cells.
  • Other types of fuel cells don't face this problem.
  • There are several advantages to hydrogen fuel cells, though.
  • Additionally, current fuel cells cannot be scaled to the small size needed for portable devices such as cell phones.