12-D reduction

Examples of 12-D reduction in the following topics:

• Rate of Microbial Death

  • Time-temperature measurements of bacterial reduction is determined by a D-value, meaning how long it would take to reduce the bacterial population by 90% or one log10 at a given temperature.
  • The target of reduction in canning is the 12-D reduction of Clostridium botulinum, which means that processing time will reduce the amount of this bacteria by 1012 bacteria per gram or milliliter.
  • The DR for C. botulinum is 12.6 seconds.
  • A 12-D reduction will take 151 seconds .
  • This curve presents the DR value (12.6 seconds) and the 12-D reduction (151 seconds) for C. botulinum.

• Exercises

  • The mean for an experimental group is 12, the mean for the control group were 8, the MSE from the ANOVA is 16, and N, the number of observations is 20, compute g and d.

• The Nernst Equation

  • In electrochemistry, the Nernst equation can be used to determine the reduction potential of an electrochemical cell.
  • In electrochemistry, the Nernst equation can be used, in conjunction with other information, to determine the reduction potential of a half-cell in an electrochemical cell.
  • ln Q is the natural log of $\frac{C^cD^d}{A^aB^b}$, where the uppercase letters are concentrations, and the lowercase letters are stoichiometric coefficients for the reaction: $aA + bB \rightarrow cC + dD$
  • Find the cell potential of a galvanic cell based on the following reduction half-reactions where [Ni2+] = 0.030 M and [Pb2+] = 0.300 M.
  • $Pb^{2+} + Ni \rightarrow Ni^{2+} + Pb, \ \ \ E^o = 0.12\ V$

• Thermodynamics of Redox Reactions

  • The thermodynamics of redox reactions can be determined using their standard reduction potentials and the Nernst equation.
  • Q is the reaction quotient $\frac{C^cD^d}{A^aB^b}$.
  • The uppercase letters are concentrations and the lowercase letters are stoichiometric coefficients for the reaction $aA + bB \rightarrow cC + dD$
  • This equation allows the equilibrium constant to be calculated just from the standard reduction potential and the number of electrons transferred in the reaction.
  • Translate between the equilibrium constant/reaction quotient, the standard reduction potential, and the Gibbs free energy change for a given redox reaction

• Models for Addition to Acyclic Substrates

  • In the following illustration, two hydride reductions of chiral methyl ketones are shown.
  • Because the new stereogenic centers are vicinal, this is termed 1,2-diastereoselectivity, and is the same for both an enantiomerically pure or a racemic reactant.
  • A number of models have been proposed to explain the diastereoselectivity of the first reduction.
  • D.
  • In a study of LiAlH4 reduction of 2-chloropropiophenone J.

• Water reduction measures

  • With offices using up to 12% or more of a nation's daily potable water, much can be done to reduce consumption without making sacrifices.

• Reduction

  • The metal hydride reductions and organometallic additions to aldehydes and ketones, described above, both decrease the carbonyl carbon's oxidation state, and may be classified as reductions.
  • The first diagram below shows how this reduction may be used to convert cyclopentanone to cyclopentane.
  • A possible mechanism for the Clemmensen reduction is displayed in the second diagram below.
  • These derivatives may be isolated and purified before continuing the reduction.
  • In the following example, 1,2-ethanedithiol is used for preparing the thioacetal intermediate, because of the high yield this reactant usually affords.

• Nitrate Reduction and Denitrification

  • The complete denitrification process can be expressed as a redox reaction: 2 NO3− + 10 e− + 12 H+ → N2 + 6 H2O.
  • Generally, several species of bacteria are involved in the complete reduction of nitrate to molecular nitrogen, and more than one enzymatic pathway have been identified in the reduction process.
  • The direct reduction of nitrate to ammonium (dissimilatory nitrate reduction) can be performed by organisms with the nrf-gene.
  • This is a less common method of nitrate reduction than denitrification in most ecosystems.
  • Outline the processes of nitrate reduction and denitrification and the organisms that utilize it

• Further Reading

• Emission