Current sensitivity

U2 = 0.1 V) and are suitable for current measurement. For smaller currents, sensitive instruments with 5 kQ per fiPc (Uj = 5 mV) are used. Small currents are usually measured by the voltage drop across a fixed resistance (calibrated shunt) using an electronic amplifier-voltmeter. This method has the advantage that the circuit does not have to be interrupted to measure the current. 

Coalescing neutron star binaries. Coalescing of neutron stars (or black holes) is foreseen to be the the most powerful source of detectable gw. The frequency of such events is estimated to be ly D/200 Mpc) and their amplitude will allow detection of sources as far as 50 Mpc. We are thus waiting for about one event every 60 years with the current sensitivity of detectors. 

IC Kwon, YH Bae, T Okano, SW Kim. Drug release from electric current sensitive polymers. J Controlled Release 17 149-156, 1991. 

The on-line coupling of HPLC and NMR can either be performed in the stopped-flow or in the continuous-flow mode (Krucker et al. 2004, Grynbaum et al. 2005, Putzbach et al. 2005, Albert et al. 2006, Hentschel et al. 2006, Rehbein et al. 2007). Current sensitivity levels are in the lower nanogram range for ID II NMR spectra and in the microgram range for 2D spectra. 

Scan pattern 0.0V -1.1OV - 1.20 V -1.1OV + 0.0 V Scan rate 4.6V sec-1 current sensitivity 200 /la per division Current above axis marker is cathodic... 

B) the heat-treatment procedure. Before heat treatment, the double layer charging currents are pronounced. After heat treatment, the charging currents are not discernible at the current sensitivity setting used. 

On entering the chamber C the ions are bent in a circular path, (refer to side view of fig. 1) pass through the slit M which is 1 mm. wide, and impinge on the plate N which makes electrical coimection with the insulated quadrants of the electrometer. The electrometer was the Compton t q5e, specially constructed in this laboratory. With a 75 volt potential on the vane, the electrometer had a sensitivity of 6500 divisions per volt. Under the conditions prevailing dining these experiments, this gave a calculated current sensitivity of 1 X 10 amperes. 

Figure 23.3 Effect of charging currents on foward half of CV scan at two different scan rates, assuming that Cd, is independent of v. Top trace is at 100 times the scan rate and 1/10 the current sensitivity of the bottom trace. The faradaic peak current, ip, is indicated. Adapted from Ref. 1, p. 221, with permission.

Fig. 6-5. RDE and HMRDE cathodic scans of nitrobenzene in 0.01 M HC104 at an amalgamated gold rotating disk. All A traces are RDE curves, all B traces are HMRDE curves. A, B are residual currents A5, B5 are for 5.0x 10-8 M and A50, B50 are for 49.2x 10-8 M. Scan rate for A, B, B5 is 1 mV/s for A50, B50, 3 mV/s. Current sensitivities indicated by markers. Upper potential scale refers to B traces, lower to A. Zero current of A on right ordinate, zero current of B is upper abscissa. Modulation and speed conditions fi1/2 = 60rpml/2, AQW2 = 6 rpm1/2, /= 3 Hz. Averaging time constant is 10 s for A, B, A5, B5, and 3 s for A50, B50. From [67].

Figure 7.3.2.2 shows the current sensitivity obtained with a capillary (c)HPLC-NMR probe with a 2.0mm Helmholtz microcoil and a detection volume of 750 nl (detection capillary, i. d. 180 xm). The signal of the anomeric protons of 0.2 M sucrose in D2O yields a signal-to-noise ratio (S/N) of 50 1. 

Figure 13.2.2 Current sensitivity test of the cHPLC-NMR probe (sample, 200 mM sucrose in D2O H resonance frequency, 600 MHz detection volume, 750 nl)...

TABLE 8.4 Activation Potentials and Current Sensitivities for the Voltanunetric Oxidation of Dissolved Hydrogen at Activated Platinum Electrodes in Five Solvents (Scan Rate 0.1 V s 1) Solubilities and Diffusion Coefficients for H2 in Several Solvents... 

Fig. 10.9. Controlled potential cathodic scans of Tl+ at an amalgamated gold disk electrode. All A scans are RDE curves, all B scans are in-phase HMRDE curves. (A, B) 0.01 mol dm" HC104 (A2, B2) 2.0 x 10-7 mol dm- TT in 0.01 mol dm- HCI04. The current sensitivities are indicated by the markers, zero current in all cases is the dashed line. For all curves ft = 3600 rpm, for HMRDE (B) Aft = 6 rpm, frequency = 3 Hz, averaging time constant is 3 s and the scan rate is 2 mV s"1 (after Reference [27]).

Yuk, S. H., Cho, S. H., and Lee, H. B. (1992), Electric current-sensitive drug delivery systems using sodium-alginate/polyacrylic acid composites, Pharm. Res., 9, 955-957. 

The use of porphyrins and porphyrin-like macrocycles, namely the texaphyrins, which show good selectivity towards tumor cells, could be used to overcome the limitations of the current sensitizers, namely a lack of suitable biolocalization and a consequent high toxicity at the needed therapeutic doses [25]. The strengths and weaknesses of this approach are detailed below. 

We have also observed that there is a dramatic dependence of the electrochemical response on the nature of the electrolyte— in particular, the existence of a specific anion effect. Figure 4 shows the effect on the scone polymer film of changing only the electrolyte anion from perchlorate to hexafluorophosphate. Not only is there a significant reduction in the size of both waves in the PF medium (note change in current sensitivity), but there is also a profound effect on the shapes of the waves. In particular, the extreme sharpness of the anodic Os /Os wave may be due, in part, to the phaselike behavior of crystalline elements in the film which form in the presence of PF as opposed to C10. Similar behavior has been observed in the effect of electrolyte cations on the response of an anionic film of Prussian blue (lh) and also the effect of various solvents on a plasma-polymerizecf vinylferrocene film (le). 

Best current sensitive and specific markers. GFAP, glial fibrillary acidic protein. 

Similar to the mouse ES model, wholecell patch-clamp studies showed that the hES cell-derived cardiomyocytes also display cardiac-specific action potential morphologies and ion currents (Fig. 12.2) [55]. Additional studies conducted in our laboratory revealed the basis for the spontaneous automaticity in these cells, at least at the mid-differentiation stages. These studies revealed that during this stage, the spontaneous electrical activity is mediated by the absence of significant inward rectifier current and a prominent Na current sensitive to TTX coupled with the... 

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