Host matrices sensitivity

Host matrix Sensitizer/ activator Emissions (nm) Host matrix Sensitizer/ activator Emissions (nm)... 

The high sensitivity and selectivity of the EPR response enables diamagnetic systems to be doped with very low concentrations of paramagnetic ions, the fate of which can be followed during the progress of a reaction. The criteria [347] for the use of such tracer ions are that they should give a distinct EPR spectrum, occupy a single coordination site and have the same valency as, and a similar diffusion coefficient to, the host matrix ion. Kinetic data are usually obtained by comparison with standard materials. 

Construction of the optode for optical biosensor requires immobilization of sensitive compounds in the host matrix. There are several methods enabling molecules entrapment. One can use gels, polymers, saccharose, various meshes and membranes78. In case of fiberoptic indirect sensors optode must be attached to the fiber tip. Nowadays, there are two commonly used optode host materials sol-gel materials and polymers. 

PTFE is commercially available in three forms (1) skived films (2) powder and (3) aqueous dispersions. Of the three forms, the aqueous dispersion provides the most suitable medium to approach a level of mixing and uniformity of the host matrix and dopant that is achieved when transparent matrices and sensitizers share... 

Abu-Rabeah, K., Marks, R.S. Impedance study of the hybrid molecule alginate-pyrrole Demonstration as host matrix for the construction of a highly sensitive amperometric... 

In the first two types of interaction although nanomaterials is not involved, the sensitivity, response, and recovery time of the ICP nanocomposite can still be affected by the combination of described principle within the host matrix. In those cases the nano-fillers are only acting as reinforcing material to enhance the sensing properties of the host conjugated polymer. 

Ce and Eu usually shows a typical broadband emission accompanied by intense broad absorption from the 5ii-4/transitions. Their emission positions can vary from ultraviolet to red, and their corresponding excitation positions can also be tuned from ultraviolet to blue light, which depends on the crystal field strength of the host matrix. Therefore, Ce " and Eu " ion are efficient sensitizers and can transfer part of their energy to activator ions. In recent years, numerous single-phased multicolor-emitting phosphors have been developed based on the energy transfer from Ce " or Eu to activators such as Mn / Eu / Tb ", Dy / Pr / and so on. 

A typical upconversion material is composed of two components, an inorganic host matrix and doping lanthanide ions (Figure 3). For achieving efficient ETU, effective energy transfer between the host matrix-embedded ions is essentially required, so the doped ions can also be divided into two types, activator (emitter) and sensitizer (absorber). 

If homogeneous samples of a similar composition are to be analysed on a routine basis, a data bank of sensitivity factors can be established for the elements and host matrices being studied. The ion current recorded for element A emitted from matrix M is written as... 

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