Total metals

Where d = total metal thiekness penetrated f = frequency (X = permeability cr = conduetivity... 

The speciation scheme of Batley and Florence requires eight measurements on four samples. After removing insoluble particulates by filtration, the solution is analyzed for the concentration of anodic stripping voltammetry (ASV) labile metal and the total concentration of metal. A portion of the filtered solution is passed through an ion-exchange column, and the concentrations of ASV metal and total metal are determined. A second portion of the filtered solution is irradiated with UV light, and the concentrations of ASV metal... 

Step in Solution of ASV- Labile Metal of Total Metal... 

Coalition ofJSlortheast Governors. The CONEG model heavy-metal guideline is implemented through state regulations and limits total metal content of lead, chromium, mercury, and cadmium. The limitation of 100 parts per million total is aimed at protecting the environment from the disposal of post-consumer waste. 

Although vitreous siUca is a simple, single-component glass, its properties can vary significantly, depending on thermal history, the type and concentration of defects, and impurities. Vitreous siUca can, however, be one of the purest commercially available glassy materials. In synthetic vitreous sihcas, for example, total metal contamination is typically measured ia the 50—100 ppb range. Even at such a low level of impurities, differences ia properties, such as uv-transmission, are observed for various siUcas. 

Machining costs (labor and overhead) in the United States have an estimated value of > 300 x 10 /yr. The cost of labor and overhead for machining is based on the estimated number of total metal-cutting machine tools in various metal-cutting industries (1). This value does not take into account the cost of raw stock (work material), cutting tools, and many other support faciUties. An estimated breakdown of cutting tool costs is given in Table 13 (172). Because of the competitive nature of these industries, most prefer to keep cost information proprietary. 

The equivalent nickel content of the feed to the FCCU can vary from <0.05 ppm for a weU-hydrotreated VGO to >20 ppm for a feed containing a high resid content. The nickel and vanadium deposit essentially quantitatively on the cracking catalyst and, depending on catalyst addition rates to the FCCU, result in total metals concentrations on the equiUbrium catalyst from 100 to 10,000 ppm. 

Proportions of CT and SO24 can be varied total metal is usually maintained at 70—90 g/L. 

The NPDES regulations (40 CFR 122.45) require effluent limits to be expressed as total recoverable metal. This requirement makes sense as a means to monitor and regulate both the total metal loading and also the effectiveness of wastewater treatment that involves chemical precipitation of the metal. 

Simple, versatile measures total metal content. Knowledge of interfering effects important. 

Scheme VIII has the form of Scheme II, so the relaxation time is given by Eq. (4-15)—appjirently. However, there is a difference between these two schemes in that L in Scheme VIII is also a participant in an acid-base equilibrium. The proton transfer is much more rapid than is the complex formation, so the acid-base system is considered to be at equilibrium throughout the complex formation. The experiment can be carried out by setting the total ligand concentration comparable to the total metal ion concentration, so that the solution is not buffered. As the base form L of the ligand undergoes coordination, the acid-base equilibrium shifts, thus changing the pH. This pH shift is detected by incorporating an acid-base indicator in the solution.

Processing times of 3-10 min are usual, giving a total metal removal of 25-50 ftm. 

Limit Fe and A1 to 0.05 ppm total metal in the supply water source... 

Polymer feed rates can be calculated based on a 1 1 stoichiometric ratio with FW hardness or total metals (Ca/Mg/Fe/Cu/Al/Ni). If, for example, a boiler operates at 950 psig, runs at 50 X COC, and is supplied with FW containing 0.05 ppm total metals, this may require 0.05 X 50 = 2.5 ppm polymer actives in the BW. 

FW total metals sampled from economizer outlet. 

Where corrosion problems exist, rates may vary considerably throughout the system, but total metal loss may typically exceed 0.25 ppm M (where M = Fe/Cu/Ni) in the condensate without the use of amine. This compares badly to recommended maximum limits of 0.05 ppm M for up to 580 psig/40 bar boilers, 0.03 ppm M for up to 870 psig/60 bar, and 0.02 ppm M beyond that. 

Fig. 25. Portions of the IR spectra of the products of the cocondensation of Ni atoms with CO/Ar (1 250). A through E refer to increasing, total-metal concentration. The inset is a curve-resolved version of spectrum B (96).

Each entry has the % of total metal present as the free hydrated ion, then the ligands forming complexes, in decreasing order of expected concentration. For instance, in inorganic freshwater at pH 9, Ag is present as the free aquo ion (65%), chloro-complexes (25%), and carbonato-complexes (9%). 

Transport in solution or aqueous suspension is the major mechanism for metal movement from the land to the oceans and ultimately to burial in ocean sediments. In solution, the hydrated metal ion and inorganic and organic complexes can all account for major portions of the total metal load. Relatively pure metal ores exist in many places, and metals from these ores may enter an aquatic system as a result of weathering. For most metals a more common sequence is for a small amount of the ore to dissolve, for the metal ions to adsorb onto other particulate matter suspended in flowing water, and for the metal to be carried as part of the particulate load of a stream in this fashion. The very insoluble oxides of Fe, Si, and A1 (including clays), and particulate organic matter, are the most important solid adsorbents on which metals are "carried."... 

Table 1 Summary of metal concentrations (in )ig of total metal concentration) causing toxicity on fluvial biofilms (in terms of effective concentrations EC50) after acute exposure (of few hours of exposure) and chronic exposure (of several weeks of exposure)...

Bimetallic Co-Mo oxide specimens were prepared via co-impregnation of calculated amounts of cobalt nitrate and ammonia heptamolybdate on y-alumina to achieve a total metal loading of 20wt% with an equimolar Co Mo ratio. Nitridation of catalysts was carried in a fixed bed... 

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