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Acceptance current

During the process of charge, the current that a secondary battery can accept for its recharge perse is limited by the kinetics of the internal electrochemical reactions. [Pg.68]

Therefore, the acceptance current is, for a given voltage imposed on the secondary battery, this maximum effective charging current. [Pg.68]

54 Kinetics denotes the rate of the chemical reactions, knowing that they are limited because the reactions caimot be instantaneous. [Pg.68]

It should also be noted that the very design of the electrodes can have an influence on the acceptance current of the element. For the same electrochemical couple, the acceptance current will be different if the cells are designed to deliver energy (lesser acceptance current) or power (greater acceptance current). [Pg.69]


Details of many synthetic processes are never reported and, hence, as noticed by Pletcher and Walsh [10], any contribution of electrosynthesis remains speculative. Crucial factors are generally the availability and costs of the starting materials, the material yield, a simple product isolation, the stability of the electrolysis medium and acceptable current densities. [Pg.144]

The second statement of Proposition 7.7, corrected by a factor of two for spin, predicts that we should find elementary states of every dimension of the form 2(2f + 1) where f is a nonnegative integer. This statement cannot be proved experimentally, as it involves an infinite number of states. Yet it is suggestive, especially in hindsight. It is a basic premise of the universally accepted current model of the hydrogen atom. In a similar vein, consider the following corollary of Proposition 7.5. [Pg.223]

It must be stressed that there is still a fair chance of arriving at electrocatalysts that would achieve reasonable anode potentials (say +0.3 V vs RHE) at technically acceptable current densities (say 0.3 to 0.4 A/cm2). The situation for the next higher alcohol, ethanol, however, is almost hopeless. Any work aimed at developing catalysts for anodic oxidation of the much more inert hydrocarbons at low temperatures will certainly be frustrated. [Pg.142]

Central lo sonic pest inanagemeiil systems is a computerized simulator which, based upon the analysis of hundreds of past observations and experiments, can accept current weather information, fur example, and read out the effects ol the weather parameters. It thus provides directions for whatever pest control actions should or should not be taken at any given lime. In essence, the simulator hikes the place of numerous observers in the field and enables an inlormation center to pass along directives- in real time. A nunther ol factors in addition to weather information, of course, can he input into the sy stem. Needless to say. if such a network were established, all manner of other information pertaining to the crop ecosystem could he handled m addition to pest management data. [Pg.850]

Electrochemical window — In electrochemical experiments the range of potentials that is accessible without appreciable current flow, i.e., the potential range in which the electrode may be considered perfectly polarizable . Electrochemical windows depend on the - electrode material, the - solvent, and the - electrolyte. There is no strict definition for the current density defining the potential limits of the electrochemical window. That depends on the experiment, i.e., the signals to be measured. For highly sensitive measurements of very low current densities, the acceptable current densities at the potential limits are much smaller than in cases where high current density signals are measured. The electrochemical window also depends very much on impurities, e.g., traces of water in nonaqueous solvents, or traces of transition metal ions in aqueous electrolyte solutions. The... [Pg.195]

All of these items reflect more the political reality of life rather than the science. To accept current approaches is to subject products to less than full development and, products and patients to possible future harm. Ultimately the science will prevail. Eventually the choice to be pro- or reactive will have to be made. Doing it right the first time saves money and time while identifying possible problems and hidden benefits of products. [Pg.115]

The origin of the Moon has been the subject of intense scientific interest for over a century but particularly since the Apollo missions provided samples to study. The most widely accepted current theory is the giant impact theory but this idea has evolved from others and alternative hypotheses have been variously considered. Wood (1984) provides a very useful review. The main theories that have been considered are as follows ... [Pg.531]

There are at least a couple of researchers who do not accept current thinking on AIDS and its treatment with AZT, namely, Peter Duesberg and David Rasnick of the University of California, Berkeley. They maintain that the AIDS virus, or HIV, is a harmless passenger virus, and the disease is instead caused by recreational and therapeutic drug use. Furthermore, AZT is in itself toxic, and in actual fact does not prevent or control AIDS, in itself producing the symptoms of AIDS as well as other adverse side effects. All this serves to demonstrate that medical research is by no means clear-cut, is possibly biased, and can be as controversial as any other endeavor.)... [Pg.181]

Property use compatibility remedy allows for acceptable current and future property use. [Pg.51]

Electrolyser of this type can be used to remove metals from their dilute solutions. For example, an electrolyser of the firm CHEMELEC (England) permits the concentration of heavy metal ions to be lowered to 100 mg per litre at an acceptable current yield (tens of per cent). The metal deposited on a plate or rod-shaped cathode can be used as an anode in galvanic plating. There were some doubts about the purity of the recovered metal, which was supposed to contain microscopic glass particles, presumably from disintegrated glass beads. If this... [Pg.61]

Selection of an appropriate solute is important for the formulation of an effective electrolyte. Maximum conductivity, for example, seems to be associated with a size homogeneity between the substituting species and the majority cation in the cubic structure, as well as its concentration in solid solution. Figure 3 presents the effects on the ionic conductivity of stabilised zirconia at a fixed temperature, on variation of the cationic substituting species. It is evident that the optimised yttrium solid solution has a conductivity of about 0.015 S cm at 800°C, so that only a very thin electrolyte membrane can provide a technically acceptable current density at that temperature. The well-established Westinghouse SOFC system therefore operates closer to 1000°C to take advantage of the rapid increase of electrolyte conductivity with temperature (7) (see also Fig. 7). This dependance, particularly steep for YSZ, is presented for several solid ionic conducting materials in Fig. 4. [Pg.345]

The working electrode is coated onto one of the windows. In order to keep the scattering from the electrolyte solution low, one window is mounted on the end of a hollow syringe barrel. For electrochemical measurements, it is retracted to provide acceptable current distribution for X-ray measurements, the barrel is moved as close as possible towards the fixed window. The poor electrochemical properties of the cell in the latter position are an obvious drawback of the cell design. [Pg.235]

The period during which the Pb/PbS04 electrode system may give or accept current depends on the ability of the Pb and PbS04 phases to exchange ions freely with each other. This time interval defines the capacity of the Pb electrode. In order to obtain high capacity, the Pb electrode is transformed into a porous mass with active surface of about 0.4-0.8 m ... [Pg.48]

Gnotobiote an animal, stock, or strain, derived by aseptic caesarean section or sterile hatching of eggs, which is reared and continuously maintained with germfree techniques under isolator conditions in which the composition of any associated fauna and flora, if present, is fully defined by accepted current methodology. [Pg.284]

There is a certain range of accepted current duration. Figure 10.18 shows some current discharge current waveforms. Note that some models use hiphasic waveforms, some use truly monophasic. [Pg.452]

How Analyte Ions Are Formed Several diverse views have been expressed on this topic [33-38]. No single model provides a complete picture of MALDI ionization. The widely accepted current view is that the analyte ionization is a two-step process a primary ionization event, followed by in-plume secondary ion-molecule reactions [34-36]. In the first step, reactive matrix ionic species are generated. The analyte ions are produced in the expanding gas plume (an area just above the matrix surface) via extensive secondary ion-molecule charge-transfer reactions between the primary matrix ions and neutral analyte molecules ... [Pg.37]

Electric fields have been used to clean membranes and to try to prevent the depo on of charged particles onto a membrane surfiice by means of electrophoresis [Bowen Sabani, 1992 Wakeman and Tarleton, 1987]. Tubular metal ndcrofiltnitian membranes are particularly suited for this application a thin metal counter-electrode positioned centrally provides acceptable current distribution. A DC elecbic field is applied to provide a current d sity of 100-200 mA cmT near to the membrane sur ce. Use of a DC field creates gas bubbles at the membrane sui ce that leads to removal of the attached particles [Fairey Microfiltrex, undated]. The membrane is the cathode to prevent oxidation at the membrane sur ce causing chemical attack of the metal. [Pg.391]

Third, the most acceptable current protocol for administering ethanol to laboratory animals is to feed a liquid diet containing 35-50% of the total calories as ethanol. With this method, the animals receive ethanol continuously, and food is almost always present in the stomach. Human alcoholics often go on binges and usually drink during a limited number of hours and, perhaps, on an empty stomach. In our study (Misslbeck et al, 1984), rats had access to the liquid diet between 3 00 p.m. and 8 00 a.m. The animals rapidly consumed about one-third of their total daily intake shortly after they were offered the diet at 3 00 p.m. Although they received a large dose of alcohol, it was still consumed in the presence of... [Pg.145]

In 2006, Path et al. continued research into this reaction, using carbon suspensions in a sulfuric acid solution to which 100 mM each of Fe + and Fe + ions had been added on purpose. It could be shown that with a voltage of 0.6 to 1.0 V applied across a cell with platinum or platinum-aUoy electrodes, even at 40°C the reaction occurs with an acceptable current density of 30 mA/cm. This is a rather promising result, since in ordinary electrolyzers a voltage of at least 1.7 V is needed for hydrogen evolution. The authors pointed out, though, that a number of aspects requiring further study are not clear with respect to the reaction. [Pg.172]

Positive Temperature Coefficient (PTC) Device This is a resettable device, connected in series with the cells, whose resistance increases rapidly when a preestablished temperature is reached, thereby reducing the current in the battery to a low and acceptable current level. The characteristics of the PTC device are shown in Fig. 5.15. It will respond to high circuit current beyond design limits (such as a short circuit) and acts like a resettable fuse. It will also respond to high temperatures surrounding the PTC device, in which case it operates like a temperature cutoff (TCO) device. [Pg.132]


See other pages where Acceptance current is mentioned: [Pg.508]    [Pg.89]    [Pg.393]    [Pg.154]    [Pg.302]    [Pg.89]    [Pg.328]    [Pg.15]    [Pg.178]    [Pg.371]    [Pg.211]    [Pg.292]    [Pg.364]    [Pg.507]    [Pg.87]    [Pg.4]    [Pg.89]    [Pg.317]    [Pg.5]    [Pg.197]    [Pg.632]    [Pg.754]    [Pg.2160]    [Pg.68]    [Pg.68]    [Pg.68]    [Pg.312]   


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