Electric hypotheses

Hypothesize Silver is the best conductor of electricity. Hypothesize why silver is not used for electric wires if it is such a good conductor of electricity. 

The mechanism of dyeing (see First Report on Colloid Chemistry, B. Ass. 1917, for the complete rdsum6 of the various theories) has received a great deal of attention and has led to the formulation of a variety of hypotheses such as the solid solution, the chemical, the adsorption and electrical hypothesis. A critical examination of the data on which these various alternative hypotheses rests would lead one to suppose that they are by no means irreconcilable with one another. 

This law differs from the electric hypothesis that chemists have hitherto defended, but which has never been able to receive a complete application to their views on organic chemistry that, on the contrary, which I advance, agrees perfecdy with the application of the theory that I proper, to the facts. 

This law is different from the electric hypothesis which chemists... 

It is not certain whether Sir Humphrey Davy (Fig. 1-7) knew of these considerations. He accepted a commission from the Admiralty for the protection of copper-clad wooden ships, which had been introduced in 1761. During his numerous laboratory experiments, he discovered the cathodic protection of copper by zinc or iron [3]. Davy had already put forward the hypothesis in 1812 that chemical and electrical changes are identical or at least arise from the same material property. He believed that chemical reaction forces could be reduced or increased by altering the electric state of the material. Materials can combine only if they have different electric charges. If an originally positive material can be artificially negatively... 

Electrochemical corrosion is understood to include all corrosion processes that can be influenced electrically. This is the case for all the types of corrosion described in this handbook and means that data on corrosion velocities (e.g., removal rate, penetration rate in pitting corrosion, or rate of pit formation, time to failure of stressed specimens in stress corrosion) are dependent on the potential U [5]. Potential can be altered by chemical action (influence of a redox system) or by electrical factors (electric currents), thereby reducing or enhancing the corrosion. Thus exact knowledge of the dependence of corrosion on potential is the basic hypothesis for the concept of electrochemical corrosion protection processes. 

In the absence of an electric field, the dome-closed conformation must be the most stable tip structure, even when spot-welds are considered, since only the perfectly dome-closed tip has no dangling bonds (i.e., it is a true hemifullerene). At the 3000°C temperature of the arc, the rate of tip annealing should be so fast that it is sure to find its most stable structure (i.e., to close as a dome). Clear evidence of this facile closure is the fact that virtually all nanotubes found in the arc deposit are dome-closed. (Even stronger evidence is the observation of only dome-closed nanotubes made at 1200°C by the oven laser vaporization method.) Such considerations constituted the original motivation for the electric field hypothesis. 

As current is passed through the cells shown in Figure 14-2, the oxygen produced in the first cell is collected and its volume is compared with the volume of chlorine produced in the center cell (the volumes being compared at identical temperatures and pressures). The volume of chlorine is found to be exactly double that of oxygen. Applying Avogadro s Hypothesis, explain how this result shows that electricity can count atoms. 

Atomic velocity distribution, 130,131 Atomic volume, 94, 98 alkali metals, 94 halogens, 97 inert gases, 91 third-row elements, 101 Atomic weight, 33 table, inside back cover Atoms, 21 conservation of, 40 electrical nature of, 236 measuring dimensions of, 245 Avogadro, Amadeo hypothesis, 25, 52 hypothesis and kinetic theory, 58 law, 25 number, 33 Azo dyes, 344... 

In a possible hypothesis, Smirnov et al. have proposed that a transient process such as [MX4]3- + [MXj] - —> [MX,] 2- + [MXJs- is the electrically conducting process. Their concept may he similar to the dynamic dissociation model. 

This hypothesis received support from the electrical studies of Braden Clarke (1974) and Crisp, Ambersley Wilson (1980), who attributed maxima in curves of permittivity and conductivity against time to the liberation of water and its subsequent reabsorption into the matrix (Figure 93a,b). Crisp, Ambersley Wilson (1980) also considered that these maxima were due to generation of both water and ionic zinc species. Subsequently, as the reaction proceeds the zinc ions are fixed as insoluble zinc eugenolate. 

Read the entire laboratory activity. Form a hypothesis as to whether distilled water is a conductor of electricity. Record your hypothesis on page 58. 

O Atrial fibrillation may be caused by both abnormal impulse formation and abnormal impulse conduction. Traditionally, AF was believed to be initiated by premature impulses initiated in the atria. However, it is now understood that in many patients AF is triggered by electrical impulses generated within the pulmonary veins.20 These impulses initiate the process of reentry within the atria, and AF is believed to be sustained by multiple reentrant wavelets operating simultaneously within the atria.21 Some believe that, at least in some patients, the increased automaticity in the pulmonary veins may be the sole mechanism of AF and that the multiple reentrant wavelet hypothesis may be incorrect.21 However, the concept of multiple simultaneous reentrant wavelets remains the predominant hypothesis regarding the mechanism of AF. 

Two hypotheses have been proposed to explain how phenolic acids directly increase membrane permeability. The first is that the compounds solubilize into cellular membranes, and thus cause a "loosening" of the membrane structure so that minerals can leak across the membrane (28-30, 42). Support for this hypothesis comes from the fact that the extent of inhibition of electrical potentials correlates with the log P (partition coefficient of a compound between octanol and water) for various benzoic and cinnamic acid derivatives (Figure 5). 

This was the original hypothesis put forward by Lee (1970) and expanded by Ogilvie et al. (1973). Secretory products of N. brasiliensis do indeed decrease the amplitude of contractions of segments of uninfected rat intestine maintained in an organ bath, but a role for AChE in this phenomenon was discounted due to the heat stability of the parasite factor, and the inability to duplicate the effect with AChE from the electric eel (Foster et al., 1994). Subsequent investigations demonstrated that the suppression of contraction could be duplicated by a 30-50 kDa fraction of secreted products, which contained a protein of 30 kDa that was immunologically cross-reactive with mammalian vasoactive intestinal peptide (VIP). Moreover, an antibody to porcine VIP significantly reduced the inhibitory effect of parasite-secreted products on contraction in vitro (Foster and Lee, 1996). 

The quintessence hypothesis was proposed by J. P. Ostriker and Steinhardt (2001). The authors use the term quintessence ( fifth substance ) to describe a quantum force field which is gravitationally repulsive. It has a certain similarity to an electrical or magnetic field and could lead to an invisible energy field which accelerates cosmic expansion. 

Stanley Miller at the University of Chicago more than 50 years ago. This experiment (in fact, of course, many were carried out prior to the successful one) is probably as well known as the Wohler synthesis of urea Miller s doctoral supervisor, Harold Urey (winner of the Nobel Prize in 1934), had suggested to Miller that he simulate a reducing primeval Earth atmosphere (as required by the Oparin-Haldane hypothesis) to electrical discharges and see what happens . Urey apparently expected that such an experiment would lead to a huge variety of organic compounds. 

Limits on Particle Charging. The electrical charge carried by a particle resides on the surface. Thus, a fundamental upper limit for particle electrification may be computed by imposing the constraint that the electric field at the surface can not exceed the dielectric strength of dry air, Eb 30 kV/cm. According to this hypothesis, the upper limit upon surface charge density becomes... 

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