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Possible Problems

Some concerns directly related to a tomizer operation include inadequate mixing of Hquid and gas, incomplete droplet evaporation, hydrodynamic instabiHty, formation of nonuniform sprays, uneven deposition of Hquid particles on soHd surfaces, and drifting of small droplets. Other possible problems include difficulty in achieving ignition, poor combustion efficiency, and incorrect rates of evaporation, chemical reaction, solidification, or deposition. Atomizers must also provide the desired spray angle and pattern, penetration, concentration, and particle size distribution. In certain appHcations, they must handle high viscosity or non-Newtonian fluids, or provide extremely fine sprays for rapid cooling. [Pg.334]

The U.S. FDA monitors foods for half of the approximately 300 pesticides having official EPA tolerances as weU as a number of other pesticides that have no official tolerances. Multiresidue methods, most of which are based on chromatography protocols, are employed (7). Not aU pesticides are monitored on aU foods and sampling (qv) is purposely biased to catch possible problems. The overaU iacidence of iUegal pesticide residue is, however, quite smaU 1% for domestic surveiUance samples and 3% for imported foods. The methods employed can usuaUy quantify residues present at 0.01 ppm. Quantitation limits range from 0.005 to 1 ppm. [Pg.241]

The calcium form of EDTA instead of free EDTA is used in many food preparations to stabilize against such deleterious effects as rancidity, loss of ascorbic acid, loss of flavor, development of cloudiness, and discoloration. The causative metal ions are sequestered by displacing calcium from the chelate, and possible problems, such as depletion of body calcium from ingestion of any excess of the free chelant, had it been used, are avoided. [Pg.393]

A possible problem of sealing the electrolyte path is found in the Foreman and Veatch cell. This can be avoided by placing the cells in a vessel. The best known example of this is the Beck and Guthke cell shown in Figure 8 (74). The cell consists of a stack of circular bipolar electrodes in which the electrolyte is fed to the center and flows radially out. Synthesis experience using this cell at BASF has been described (76). This cell exhibits problems of current by-pass at the inner and outer edge of the disk cells. Where this has become a serious problem, insulator edges have been fitted. The cell stack has parallel electrolyte flow however, it is not readily adaptable to divided cell operation. [Pg.91]

Shock load The arrival at a plant of a waste which is toxic to organisms in sufficient quantity or strength to cause operating problems. Possible problems include odors and sloughing off of the growth or slime on a trickling-filter media. Organic or hydraulic overloads also can cause a shock load. [Pg.626]

The examples in this subsection illustrate some possible problems and solutions. [Pg.1052]

Despite these potential benefits, there are possible problems associated with the use of generic safety audit systems. Questions that need to be considered in the case of such standardized audits include ... [Pg.53]

In any form of analysis it is important to determine the integrity of the system and confirm that artefacts are not produced as a by-product of the analytical procedure. This is particularly important in enantiomeric analysis, where problems such as the degradation of lactone and furanon species in transfer lines has been reported (40). As chromatography unions, injectors, splitters, etc. become more stable and greater degrees of deactivation are possible, problems of this kind will hopefully be reduced. Some species, however, such as methyl butenol generated from natural emissions, still remain a problem, undergoing dehydration to yield isoprene on some GC columns. [Pg.65]

The casing string for a certain well is to consist of 13-f-in. casing with coupling outside diameter of 14.375 in. Determine the required outside diameter of the drill collar in order to avoid possible problems with running casing if the borehole diameter is assumed to be 17- in. [Pg.717]

Possible problems of inter-coat adhesion with unweathered high-gloss coats ... [Pg.127]

DESIGN IN RELATION TO WELDING AND JOINING Table 9.9 Possible problems in less commonly welded metals... [Pg.97]

One of the possible problems of using the complex mixtures is the presence of unwanted materials such as certain metal ions, particularly manganese and iron. In addition, inhibitory compounds such as acetic add may be present All need to be removed before fermentation can proceed. [Pg.132]

Acid chlorides are very reactive and at room temperature react readily with amines. Synthesis by interfacial and solution methods is possible. However, care should be taken that the hydrochloric acid produced does not react with unreacted amine groups. With the strong basic aliphatic diamines, the acid binder must preferably be even more basic. The attainable molecular weights are strongly dependent on the concentrations this is particularly the case for easily precipitated terephthalamide polymers. Possible problems with the acid binder can be overcome by starting with silylated diamines.33,34 A typical example for interfacial polymerization of terephthalamides is PA-2,T.66... [Pg.182]

Quantity of Duplicate Systems (Possible problem with data Integrity where data held and duplicated in several systems) Greater than 5 systems 2 ... [Pg.229]

Optical sensors and relay switches are used throughout the test routine for verification. For all possible problems, as well as the sequence in which they occur, the robot must recognize that there is a problem, define the problem, decide how best to resolve the problem, perform the necessary operations to overcome the problem, and enable the system to resume testing. This is an AI application area and a critical feature, mainly because the system operates unattended and measurements are taken overnight and during weekends. [Pg.34]

Siderophores like desferrioxamine may, therefore, find increasing applications not only in the treatment of iron poisoning and iron-overloaded disease states but also as chemotherapeutic agents, although the possible problems noted above cannot be ignored. [Pg.474]

As explained by Franks (1972), this again shows that the component balance equations, for the different components of the mixture, will thus have different time constants, which depend on the relative magnitudes of the equilibrium constants K and which again can lead to possible problems of numerical stiffness. [Pg.211]

Surface Adsorption Hater sample is passed through a column of the adsorbent and the adsorbed organic constituents subsequently eluted with a smaller volume of organic solvent. All sample types Adsorbents Include charcoal, macroretlcular resins, polyurethane foams, bonded phases and ion-exchangers. Generally have high capacity but sample discrimination may be a -problem. Sample modification and Incomplete recovery are further possible problems. [Pg.376]

Based on this patient s information, create a care plan for the management of his IE. Be sure to include (1) a statement regarding treatment requirements and/or possible problems, (2) goals of therapy, (3) a patient-specific plan, including preventive plans, and (4) a follow- up plan to assess whether the goals have been met and to determine whether the patient experienced any adverse effects. [Pg.1102]

Table 11 Possible Problems Associated with Parenteral Delivery... Table 11 Possible Problems Associated with Parenteral Delivery...
Rulkens, W.H. and Assink, J.W., Extraction as a Method for Cleaning Contaminated Soil Possibilities, Problems and Research, 5th National Conference on Management of Uncontrolled Hazardous Waste Sites, Washington, DC, 1984, pp. 576-583. [Pg.569]

Competence Information Evaluation of possible problems Every user must be competent (Certificate of Competence required in UK) Workers must be supplied with sufficient information and guidance Product selection How to comply with the conditions of approval Selection of protective clothing How to avoid spray drift How to avoid environmental damage Need to warn neighbours and others who may tie affected etc. [Pg.78]


See other pages where Possible Problems is mentioned: [Pg.347]    [Pg.604]    [Pg.683]    [Pg.192]    [Pg.474]    [Pg.124]    [Pg.483]    [Pg.133]    [Pg.132]    [Pg.1085]    [Pg.26]    [Pg.463]    [Pg.79]    [Pg.27]    [Pg.329]    [Pg.273]    [Pg.120]    [Pg.71]    [Pg.161]    [Pg.257]    [Pg.332]    [Pg.347]    [Pg.56]    [Pg.897]    [Pg.675]    [Pg.40]    [Pg.243]    [Pg.354]    [Pg.50]   


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