Franklin currents

The early pioneers also include Benjamin Franklin and Charles de Coulomb. Franklin studied the effect of point electrodes in drawing electric currents. Coulomb discovered that a charged object gradually loses its charge i.e., he actually discovered the electrical conductivity of air. Coulomb s importance for the development of electrostatic air-cleaning methods is great, mainly because the present theories about electric charges and electric fields are based on his work. 

It is particularly difficult to study charge transfer reactions by the usual internal ionization method since the secondary ions produced will always coincide with ions produced in primary ionization processes. Indeed these primary ions frequently constitute the major fraction of the total ion current, and the small intensity changes originating from charge transfer reactions are difficult to detect. For example, Field and Franklin (5) were unable to detect any charge transfer between Xe + and CH4 by the internal ionization method although such reactions have been observed using other techniques (3, 9,22). 

Figure 14-3 A circuit with a battery and a resistor. Benjamin Franklin investigated static electricity in the 1740s. 1 He thought electricity was a fluid that flows from a silk cloth to a glass rod when the tod is rubbed with the cloth. We now know that electrons flow from glass to silk. However, Franklin s convention for the direction of electric current has been retained, so we say that current flows from positive to negative—in the opposite direction of electron flow...

The Plasma Chromatograph (PC, registered trademark of the Franklin GNO Corp.) is also an instrument which does not depend on the use of magnetic fields (33). It should be well suited for the study of macroions because (a) the currents measured are well within the range of a Faraday cage-vibrating-reed electrometer detector system, and (b) the instrument operates at atmospheric pressure, thus making unnecessary the reduction in pressure from that of the electrospray chamber. 

The simple series RLC electrical circuit of Fig. 9.2 consists of a direct-current (DC) power source (here a 3-V battery), a relay, and three loads in series a resistor of resistance R, a capacitor of capacitance C, and an inductor of inductance L. Assume first a DC potential E = E0, in series with R, C, and L the capacitance stores charge, the inductance stores current, and the resistance dissipates some of the current into Joule13 heating. The arrow shows the direction of the current (which, thanks to Franklin s unfortunate assignment, is the direction of motion of positive holes—that is, the opposite of the flow of negative electrons) the relay across L avoids conceptual difficulties about an initial current through the inductor. The current is usually denoted by I (from the French word "intensite"). These three components (R, C, and L) will be explored in sequence. 

FILUP (Franklin Institute Laboratories Universal Pulser). This instrument is used for testing Electro-Explosive Devices (EED s) (See in Vol 5 of Encycl, p E63-L). It supplies constant current or constant voltage pulses of varying magnitude duration. It is also capable of measuring EED s resistance and functioning times and provides containment for the initiator being tested. The instrument is described in Ref 2 and a more recent version is described in Ref 3... 

Franklin, S.J. (2001) Lanthanide-mediated DNA hydrolysis. Current Opinion in Chemical Biology, 5,201-208. Komiyama, M., Takeda, N., and Shigekawa, H. (1999) Hydrolysis of DNA and RNA by lanthanide ions mechanistic studies leading to new applications. Chemical Communications, 1443-1451. 

Information gained from assays and future potential The application of esterases assays have provided the first direct evidence that cell lysis (as distinguished from loss terms such as grazing and sedimentation) may be an important factor in marine systems (see Kirchman, 1999). While the meaning of cell lysis, its incidence and ecological importance remain unclear (see Franklin et al, 2006), and there are concerns about the assay, we currently lack objective, independent methods with which to measure lysis (cf, Agusti and Duarte, 2002). In future, it may be possible to identify particular esterases that are truly found only within cells and choose substrates that are more specific for them. 

Andre Marie Ampere (1775-1836), French mathematician and physicist, was the first to apply mathematics to the study of electrical current. Consistent with Benjamin Franklin s definitions of positive and negative charge. Ampere defined a positive current to be the direction of flow of positive charge. Although we now know that negative electrons cairy current in metals. Ampere s definition has survived to the present. The unit of cunent, the ampere, is named in his honor. 

Current address Union Camp Corporation, Franklin, VA 23851. 

Figure 7.25 The inverted Y configuration of a direct current plasma jet. [Courtesy of Thermo-Elemental, Franklin, MA (www.thermo.com).]...

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