Radio frequency labels

The homonuclear dipolar recoupling technique of radio frequency-driven recoupling (RFDR) involves a hard n pulse per rotor period and its recoupling mechanism is based on the modulation of chemical shift difference [35-37]. When the delta-pulse approximation is relaxed so that the pulse width of the 7t pulse is about one-third of the rotor period, the so-called finite-pulse RFDR (fpRFDR) could selectively reintroduce the homonuclear dipole-dipole interaction under fast MAS conditions [38], Because the recoupling mechanism of fpRFDR does not require the presence of chemical shift difference, it can be applied to study samples with a singly labeled site. For the study of amyloid fibrils, the technique of fpRFDR is usually applied in a constant-time framework (see below). 

Fig. 10.4 Experimental scheme for the 2D [ N. HJ-TROSY using single transition to single transition polarization transfer (box labeled ST2-PT). On the lines marked H and 15N, narrow and wide bars stand for nonselective 90° and 180° radio-frequency pulses, respectively. The delay t=2.7 ms (see text). The line marked PFG indicates the pulsed magnetic field gradients applied along the z-axis G, amplitude 30 G/cm, duration 1 ms G2, 40 G/cm, 1 ms G3, 40 G/cm, 1 ms ...

A continuous monocrystalline sapphire (A1203) fibre has been prepared as single-crystal fibres by LaBelle and Mlavsky using a modified czochralski puller and radio frequency heating. The technique adopted in this method is called edge-defined film-fed growth (EFG) [18-22], Figure 3.4 shows a schematic of the EFG method. 

Depending on the requirements of the operation, this system may also include breakdown or aggregation of inventory received into smaller or larger stock keeping units (SKUs) for onward distribution. It may also include interfaces to purchase order systems, labeling applications, automated materials handling systems such as sortation systems, stock location systems, automated storage and retrieval systems. Radio Data Terminals (RDTs), Radio Frequency Identihcation units... 

It is clear that each of the label types discussed here has its own unique virtue. For example, nuclei are ideal probes for use in transient NMR studies. The F nuclei are relatively easy to see and the resonance lines are narrow (about 1 G), making them easy to manipulate with radio frequency pulses. By contrast, nuclei are more difficult to observe, but the quadrupolar interactions are very sensitive to both the presence and type of molecular motion. While spin labels are chemically complex and sufficiently large that steric effects may retard their motion into coal, their large electron spin is easy to detect at concentrations a thousand times less than those used for NMR studies. Thus these various labels are not competing, but rather complementary, probes of the coal structure. As shown in Figure 8, their concerted use enables us to probe molecular motions varying in rate by more than six orders of magnitude. 

Potyrailo, R. et al. Label-free biosensing using passive radio-frequency identification sensors. Solid- State Sens., Actuators, Microsyst. Int. Conf., pp. 2378-2380,2009. 

Nowadays people demand packaging with clear identification and labeling that is easy to open and use. Plastic packaging evolves to provide exactly that. For instance, in the near future plastic packaging will integrate printable radio-frequency identification chips based on conductive polym s, providing precious information on the quality... 

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