Milli-equivalent

Milli equivalents per liter (incq/1). = Equivalents per million... 

In treated water for high-pressure boilers or where radiation effects are important, as in some nuclear projects, impurities are measured in very small units (e.g. g/litre or p.p. 10 ), but for most purposes it is convenient to express results in mg/litre. In water analysis, determinations (except occasionally for dissolved gases) are made on a weight/volume basis but some analysts still express results in terms of parts per million (p.p.m.). The difference between mg/litre and p.p.m. is small and for practical purposes the two units are interchtmgeable. For some calculations, the use of milli-equivalents per litre or equivalents per million (e.p.m.) has advantages but has not found much application. Hardness, whatever the constituent salts, is usually expressed as p.p.m. CaCOs (see Table 2.10). 

Hence number of milli-equivalents = number of mL x normality. If the volumes of solutions of two different substances A and B which exactly react with one another are VA mL and VB mL respectively, then these volumes severally contain the same number of equivalents or milli-equivalents of A and B. Thus ... 

Now number of mini-equivalents of HC1 = number of milli-equivalents of AgN03 ... 

The checkers used beads of chloromethylated polymer available from Bio. Rad. Laboratories, Richmond, California (Bio Beads S-X2). Chlorine analysis (Note 3) showed that the resin contained 1.06 milli-equivalents of chlorine per gram, as specified by the manufacturer. 

Peroxide value Not greater than 0.02 (milli-equivalents of oxygen per kilo... 

Fig. 2. Piper diagram showing major composition (Piper, 1944). Values for ions are in percent milli-equivalents per litre.

H+ ions. Addition of 0.164 milli-equivalents of cations per millimole of NaP03 increases the rate constant K for the degradation of polyphosphates at pH 8 and 60°C by the following factors relative to the constant K0 in absence of added salts 361). 

Membranes are also characterized by their ion exchange capacity (IEC) - milli-equivalents (meq) of sulfonic acid/dry weight of membrane. The relationship between IEC and EW can be expressed... 

Figure 7. Sediment profiles of base cations in treatment basin (shaded bar) and reference basin (unshaded bar), 5-m sites, October 1987. Key a, total b, organic fraction and c, exchangeable fraction. All are expressed in milli-equivalents per 100 g of wet sediment.

In BOD measurement, the sample volume is usually 300 mL. The milli-equivalent weight for oxygen is 8000. 

After items one through seven above plus the water source are entered into the screen shown in Figure 10.8, the feed water analysis is entered. The input screen can be accessed from the menu under "Options," or by clicking on the "+/-" button on the input screen (located just left of the "Water Type" button). The designer can enter water quality data as either ppm as ion, ppm as calcium carbonate, milli-equivalents per liter or milli-moles per cubic meter. 

The Feed analysis screen is reached via the menu under "Tools— Input—Water Analysis," or by the "HzO" button at the top of the main screen. Up to three feed analyses can be entered. Concentration can be entered as ppm ion, ppm as calcium carbonate, or as milli-equivalence per liter. Standard species, such as calcium and sodium, are entered. There is also space for four designer-defined species of interest. Examples of designer-defined species include total organic carbon, boron, and the like. Note that the program will not automatically calculate permeate and concentrate concentrations for these designer-defined species. 

Schematic 1. The structure of 2 1 layered silicates. M is a monovalent charge compensating cation in the interlayer and x is thedegree of isomorphous substitution, which for the silicates of interest is between 0.5 and 1.3. The degree of isomorphous substitution is also expressed as a cation exchange capacity (CEC) and is measured in milli-equivalents/g.

Calculation Determine the Peroxide Value (PV, milli-equivalent peroxide per kilogram of sample) using the following equation ... 

A thin film of silicone grease may be applied to ground-glass joints Procedure. Air-dry a portion of the sample in a Buchner funnel and then heat in a vacuum oven at 55 to 60° for 3 hrs or until const wt is obtained. Transfer an accurately weighed portion of from 2 to 3 milli-equivalents (0.2991 to 0.4366 g) of the dried sample to a... 

The dosage of lithium must be regulated on an individual basis. The level of couceutratiou in the blood must be approximately between 0.8-1.4 milli-equivalents per liter of blood. For this reason blood samples must be taken regularly when a person is receiving lithium treatment. When the concentration of lithium is too low, the desired results will not be obtained and if it is too high, there may be adverse side effects. 

The ion-exchange capacity of a resin is defined as the number of ion-exchange sites per weight equivalent of the column packing. It is typically expressed in terms of milli equivalent per gram resin (mequiv/g) ). 

U.S. Geological Survey Sample no. Rain- fall (milli- meters) pH Antecedent sulfur dioxide (parts per billion times days) Net sulfate ion in runoff (milligrams per liter) Hydrogen ion loading (milli-equivalents per meter squared) Surface recession (micro- meters)... 

Hydrogen ion loading (milli-equivalents per meter squared)... 

Recent studies in our laboratories have been concerned with the physical properties of sulfonated ionomers such as sulfonate ethylene/propylene/ethylidene norbornene terpolymers (4, or lightly sulfonated polystyrene (S-PS) (11). These ionomers exhibit pronounced ion pair association (at sulfonate levels > 15 milli-equivalents/100 g polymer) to a degree that they appear crosslinked covalently. These interactions can be dissipated by the addition of a polar additive, thereby showing that such associations are indeed physical and do not arise due to covalent crosslinking. 

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