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Conductivity with Additives

The conductivity of nonconducting organic materials can sometimes be increased using additives called antistatic additives. Examples of antistatic additives include water and polar solvents, such as alcohols. Water is effective only when it is soluble in the offending liquid, because an insoluble phase gives an additional source of separation and charge buildup. [Pg.336]

Permissible Vessel and Surrounding Area Must be Free from Flammable Vapors, Gases, and Liquids [Pg.337]


Bjornson also measured the specific conductance of a solution of 0.01m lithium bromide in acetone with various amounts of dimethyl bromosuccinate added and found a slight linear decrease in specific conductance with addition of dimethyl bromosuccinate. These results, along with those of Olson and Cunningham, lent support to Bjornson s postulate, in that when the acidic hydrogens of bromosuccinic acid were replaced with methyl groups, or the bromide ions of lithium bromide were replaced with perchlorate ions, the increase in specific conductance was not observed. [Pg.264]

Static electricity controls—bonding and grounding, relaxation, and increasing process stream conductivity with additives.f ... [Pg.1490]

In the experiments conducted with additives the amount of additive was kept around 10 % of the solid material. From the point of view of solid waste disposal and possible utilization of this product, the CaS03/CaS04 ratio plays an important role. In general, CaS03 is not desired in the product. The contact time in the spray drier was less than one second. On the other hand, residence time in a conventional spray drier is between 5 and 12 seconds. Results of this work showed that over 70% SO2 removal could be achieved in such a short contact time. This indicates that most of the sorption reaction takes place in a small region around the nozzle. Reaction between SO2 and droplets takes place with a simultaneous evaporation. After the drying is completed the reaction probably continues, but at a relatively slower rate in the presence of moisture. If the relative humidity is not sufficiently high, no ftirther sorption of SO2 can be expected after completion of the evaporation step. [Pg.503]

Figure 14 A strategy for using SPME-MS-MVA as a dairy QC screening tool. Rapid screening is performed using a GC/MS as an e-nose to estimate shelf life of fresh processed milk subsequent checking of suspect samples (i.e., those with unusually short shelf life) can be conducted with additional manipulation of the TIC GC/MS file by trained chemists (e.g., at a corporate research chemistry lab) without the need for retesting samples. MVA based on mass intensity data. Figure 14 A strategy for using SPME-MS-MVA as a dairy QC screening tool. Rapid screening is performed using a GC/MS as an e-nose to estimate shelf life of fresh processed milk subsequent checking of suspect samples (i.e., those with unusually short shelf life) can be conducted with additional manipulation of the TIC GC/MS file by trained chemists (e.g., at a corporate research chemistry lab) without the need for retesting samples. MVA based on mass intensity data.
This is an analysis frequently conducted on oil lubricants. Generally, the additive is known and its concentration can be followed by direct comparison of the oil with additive and the base stock. For example, concentrations of a few ppm of dithiophosphates or phenols are obtained with an interferometer. However, additive oils today contain a large number of products their identification or their analysis by IR spectrometry most often requires preliminary separation, either by dialysis or by liquid phase chromatography. [Pg.62]

Sulfonation can be conducted with naphthalene—92 wt % H2SO4 in a 1 1.1 mole ratio with staged acid addition at 160°C over 2.5 h to give a 93% yield of the desired product (20). Continuous mono sulfonation of naphthalene with 96 wt % sulfuric acid in a cascade reactor at ca 160°C gives... [Pg.491]

If olefins with electron-withdrawing substituents are involved, the addition can be conducted with a basic catalyst. [Pg.135]

Manufacture. Aqueous sodium hydroxide, sodium bicarbonate, sodium carbonate, or sodium sulfite solution are treated with sulfur dioxide to produce sodium metabisulfite solution. In one operation, the mother Hquor from the previous batch is reinforced with additional sodium carbonate, which need not be totally in solution, and then is treated with sulfur dioxide (341,342). In some plants, the reaction is conducted in a series of two or more stainless steel vessels or columns in which the sulfur dioxide is passed countercurrent to the alkaH. The solution is cooled and the sodium metabisulfite is removed by centrifuging or filtration. Rapid drying, eg, in a stream-heated shelf dryer or a flash dryer, avoids excessive decomposition or oxidation to which moist sodium metabisulfite is susceptible. [Pg.149]

Analysis and Specifications. Typical product analyses include sohds level, ash, color, conductivity, purity, and minor saccharide levels (19). Specifications for anhydrous and monohydrate crystalline dextrose are available (15). High quahty anhydrous dextrose produced for the pharmaceutical industry is prepared in accordance with additional specifications (20). [Pg.292]

Polyurethane sealant formulations use TDI or MDI prepolymers made from polyether polyols. The sealants contain 30—50% of the prepolymer the remainder consists of pigments, fiUers, plastici2ers, adhesion promoters, and other additives. The curing of the sealant is conducted with atmospheric moisture. One-component windshield sealants utili2e diethyl malonate-blocked MDI prepolymers (46). Several polyurethane hybrid systems, containing epoxies, siUcones, or polysulfide, are also used. [Pg.350]

Several clinical trials have been conducted with streptokinase adrninistered either intravenously or by direct infusion into a catheterized coronary artery. The results from 33 randomized trials conducted between 1959 and 1984 have been examined (75), and show a significant decrease in mortaUty rate (15.4%) in enzyme-treated patients vs matched controls (19.2%). These results correlate well with an ItaUan study encompassing 11,806 patients (76), in which the overall reduction in mortaUty was 19% in the streptokinase-treated group, ie, 1.5 million units adrninistered intravenously, compared with placebo-treated controls. The trial also shows that a delay in the initiation of treatment over six hours after the onset of symptoms nullifies any benefit from this type of thrombolytic therapy. Conversely, patients treated within one hour from the onset of symptoms had a remarkable decrease in mortaUty (47%). The benefits of streptokinase therapy, especially in the latter group of patients, was stiU evident in a one-year foUow-up (77). In addition to reducing mortahty rate, there was an improvement in left ventricular function and a reduction in the size of infarction. Thus early treatment with streptokinase is essential. [Pg.309]

Conduction with Change of Phase A special type of transient problem (the Stefan problem) involves conduction of heat in a material when freezing or melting occurs. The liquid-solid interface moves with time, and in addition to conduction, latent heat is either generated or absorbed at the interface. Various problems of this type are discussed by Bankoff [in Drew et al. (eds.). Advances in Chemical Engineering, vol. 5, Academic, New York, 1964]. [Pg.557]

Determination of Na " and Na" ions in raw cosmetic materials was conducted with the developed method of flame photometry. A necessity of development of method of samples preparation arose up in the work process, as this spicily-aromatic raw material contained pectin in amount 0.1-0.5% and that prevented preparation of samples by standard method of extracts dilution and required incineration of analyzed sample, time of analysis was increased in 60 times. It was established that CaCl, solution with the concentration 0,4 % caused destmctions of the carbopol gel. It was established that the addition of 0,1% CaCl, and 0,1% NaCl salts solutions into the system intensified the effect of negative action of these salts onto the gel stmcture and the gel destmcted completely. [Pg.375]

The addition of hydrogen fluoride to acetylene has been widely investigated because the initial product, vinyl fluoride, is a commercially important monomer Acetylene reacts with hydrogen fluoride in the liquid phase in the absence of catalyst to give vinyl fluoride and 1,1 -ditluoroethane in modest yields [7 ], but better results are achieved by conducting the addition with various additives or catalysts... [Pg.57]

The P —alumina structures are remarkable not only for their ionic conductivities but also for the versatility in isomorphous replacement. There is little of the structure of (Na2S)l+Jt 11A1203 which cannot be substituted, at least in part, by an alternative ion. MgO and Li20 are preferred additives to P —alumina in order to obtain good ionic conduction with no electronic contribution. [Pg.577]

A study over a broader range of disulfonate monosulfonate ratios was then conducted with a series of AOS 2024 surfactants. Results are shown in Fig. 5. The carbon number and hydrophobe branching were held constant. The AS HAS ratio was 75 25. At a disulfonate monosulfonate ratio (D M) of 7 93, addition of less than 200 ppm calcium ion decreased solution transmittance to less than 10% of its initial value. When the disulfonate content of AOS 2024 was increased to 38 wt % (di monosulfonate ratio of 38 62), slightly more than 1000 ppm calcium ion was required to reduce solution transmittance to less than 10% of its initial value. When the surfactant consisted predominantly of disulfonate (di monosulfonate ratio of 84 16), the addition of more than 41,000 ppm calcium ion reduced the transmittance by less than 5% from its initial value. [Pg.380]

Fluorine doping modifies the optical properties and is accomplished by the addition of CFjBr in the gas stream. Doping results in a considerable increase in electrical conductivity with a resistivity as low as S.IO " Qcm.P2]... [Pg.308]


See other pages where Conductivity with Additives is mentioned: [Pg.157]    [Pg.336]    [Pg.180]    [Pg.277]    [Pg.78]    [Pg.117]    [Pg.104]    [Pg.157]    [Pg.336]    [Pg.180]    [Pg.277]    [Pg.78]    [Pg.117]    [Pg.104]    [Pg.811]    [Pg.1071]    [Pg.581]    [Pg.265]    [Pg.86]    [Pg.218]    [Pg.464]    [Pg.71]    [Pg.455]    [Pg.309]    [Pg.1681]    [Pg.136]    [Pg.3]    [Pg.160]    [Pg.54]    [Pg.547]    [Pg.382]    [Pg.627]    [Pg.69]    [Pg.132]    [Pg.243]    [Pg.187]    [Pg.153]    [Pg.13]    [Pg.341]    [Pg.353]   


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