Rough gauge

The quotient of rate constants obtained in steady-state treatments of enzyme behavior to define a substrate s interaction with an enzyme. While the Michaelis constant (with overall units of molarity) is a rate parameter, it is not itself a rate constant. Likewise, the Michaelis constant often is only a rough gauge of an enzyme s affinity for a substrate. 2. Historically, the term Michaelis constant referred to the true dissociation constant for the enzyme-substrate binary complex, and this parameter was obtained in the Michaelis-Menten rapid-equilibrium treatment of a one-substrate enzyme-catalyzed reaction. In this case, the Michaelis constant is usually symbolized by Ks. 3. The value equal to the concentration of substrate at which the initial rate, v, is one-half the maximum velocity (Lmax) of the enzyme-catalyzed reaction under steady state conditions. 

Attraction and repulsion of water can be roughly gauged by shaking a solid in powdered form with a mixture of water and an immiscible organic liquid, e.g., water and benzene. Substances such as clay, which go into the aqueous phase, are described as hydrophilic (water-liking) and substances such as mercuric sulfide, which go into the organic liquid, are termed hydrophobic (water-hating). 

Parts Difficult to Make by Established Techniques These include radar waveguides, surface roughness gauges, and fountain pen caps. Electroforming technology is used in the aerospace industries to manufacture lightweight precision parts such as waveguides, anteimae, and rocket thrust chambers. 

Figure 2. Roughness gauge on V step measurement (left) and 2 iterations sampling (right)...

Figure 3. Measured values of Ra for different scanning density measurements over the EDM roughness gauge...

The distribution of wavelengths and the physiology of the human eye work together to allow us to very roughly gauge temperature by its appearance, as shown in Table 1.1. 

Figure 1. Schematic representation of the calcium mass spectrum in (a) natural materials, (b) a Ca- Ca tracer solution used for separating natural mass dependent isotopic fractionation from mass discrimination caused by thermal ionization, and (c) a typical mixture of natiwal calcium and tocer calcium used for analysis. The tracer solution has roughly equal amounts of Ca and Ca. In (c) the relative isotopic abundances are shown with an expanded scale. Note that in the mixed sample, masses 42 and 48 are predominantly from the tracer solution, and masses 40 and 44 are almost entirely from natural calcium. This situation enables the instrumental fractionation to be gauged from the Ca/ Ca ratio, and the natural fractionation to be gauged from the sample Ca/ Ca ratio.

Measurement of pressures in the rough vacuum range can be carried out relatively precisely by means of vacuum gauges with direct pressure measurement. Measurement of lower pressures, on the other hand, is almost always subject to a number of fundamental errors that limit the measuring accuracy right from the start so that it is not comparable at all to... 

U-tube vacuum gauges fiiied with mercury are the simpiest and most exact instruments for measuring pressure in the rough vacuum range (1013 to a... 

Skeptical observers might wonder if the DNA found in ancient bodies or bones are actually contaminants. PCR amplifies any DNA in the sample, whether it came from the artifact or not. DNA introduced into the sample by humans who handle the artifact is a common headache for ancient DNA research, particularly for bones, which are porous. Bone porosity increases about four or five times after death, which provides a rough field test for archaeologists to gauge the age of a bone—old bones are much more porous. But the increased porosity means that these bones soak up solutions and chemicals, some of which can contain DNA. For the bones of ancient humans, including the Iceman, in which the DNA sequence is expected to be quite closely related to modern humans, it may be difficult to decide if the DNA is ancient or if it is a modern contaminant. 

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