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  2. Gram matrix - Wikipedia

    en.wikipedia.org/wiki/Gram_matrix

    The Gram matrix is symmetric in the case the inner product is real-valued; it is Hermitian in the general, complex case by definition of an inner product. The Gram matrix is positive semidefinite, and every positive semidefinite matrix is the Gramian matrix for some set of vectors. The fact that the Gramian matrix is positive-semidefinite can ...

  3. Green chemistry metrics - Wikipedia

    en.wikipedia.org/wiki/Green_chemistry_metrics

    A metric similar to reaction mass efficiency is the effective mass efficiency, as suggested by Hudlicky et al. [9] It is defined as the percentage of the mass of the desired product relative to the mass of all non-benign reagents used in its synthesis. The reagents here may include any used reactant, solvent or catalyst.

  4. Glass batch calculation - Wikipedia

    en.wikipedia.org/wiki/Glass_batch_calculation

    [1] [2] [3] The symbol "T" stands for the matrix transpose operation, "−1" indicates matrix inversion, and the sign "·" means the scalar product. From the molarities matrices N, percentages by weight (wt%) can easily be derived using the appropriate molar masses .

  5. Geometry index - Wikipedia

    en.wikipedia.org/wiki/Geometry_index

    In coordination chemistry and crystallography, the geometry index or structural parameter (τ) is a number ranging from 0 to 1 that indicates what the geometry of the coordination center is. The first such parameter for 5-coordinate compounds was developed in 1984. [ 1 ]

  6. Molar mass distribution - Wikipedia

    en.wikipedia.org/wiki/Molar_mass_distribution

    The ratio of the mass average to the number average is called the dispersity or the polydispersity index. [3] The mass-average molecular mass, M w, is also related to the fractional monomer conversion, p, in step-growth polymerization (for the simplest case of linear polymers formed from two monomers in equimolar quantities) as per Carothers ...

  7. Mass fraction (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Mass_fraction_(chemistry)

    Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...

  8. Equivalent weight - Wikipedia

    en.wikipedia.org/wiki/Equivalent_weight

    However, one gram of hydrogen reacts with 8 grams of oxygen to give water or with 35.5 grams of chlorine to give hydrogen chloride: hence 8 grams of oxygen and 35.5 grams of chlorine can be taken to be equivalent to one gram of hydrogen for the measurement of equivalent weights. This system can be extended further through different acids and bases.

  9. Mass chromatogram - Wikipedia

    en.wikipedia.org/wiki/Mass_chromatogram

    A mass chromatogram is a representation of mass spectrometry data as a chromatogram, where the x-axis represents time and the y-axis represents signal intensity. [1] The source data contains mass information; however, it is not graphically represented in a mass chromatogram in favor of visualizing signal intensity versus time.