Quartz crystal micro balance

Quantum chemical calculations, 172 Quantum chemical method, calculations of the adsorption of water by, 172 Quantum mechanical calculations for the metal-solution interface (Kripsonsov), 174 and water adsorption, 76 Quartz crystal micro-balance, used for electronically conducting polymer formation, 578... 

In this paper we present a brief topical account of the kinetic possibilities and limitations of the EQCM. Extensive review chapters with theoretical aspects of the quartz crystal micro-balance have been written by Buttry and Ward [3-5] and the reader is referred to them for a more detailed discussion. 

The quartz crystal micro-balance (QCM), the most extensively studied shear mode AT-cut quartz resonator, is comprised of a thin slice of quartz single crystal with two metal electrodes deposited on both faces of the crystal. These excitation electrodes generate a transverse shear wave across the thickness of the crystal that propagates into the film immobilized onto the crystal surface. When the over-layer is non-rigidly coupled to the... 

Quartz crystal micro balance shows promise in its applications for chemical sensing. A proper and selective coating on the surface of a QCM can be used to selectively absorb a chemical species. The mass of the absorbed species, even in very minute quantity, can be used to quantify the species present. It is an effective means for chemical sensing under appropriate circumstance. 

Smith, A.L., Shirazi, H.M., and Mulligan, S.R. Water sorption isotherms and enthalpies of water sorption by lysozyme using the quartz crystal micro-balance/Heat-conduction calorimeter, Biochim. Biophys. Acta — Protein Struct. Mol. Enzymol., 1594,150, 2002. 

L. Alfonta, I. WQlna-, D.J. Throckmorton, and A.K. Singh, Electrochemical and quartz crystal micro-balance detection of the cholera toxin employing horseradish peroxidase and GMl-functionalized Upo-somes. Anal. Chem. 73,5287-5295 (2001). 

Liu, M.-H. and Y.O. Su (1999). Electrocatalytic reactions by an iron porphyrin/ polypyrrole modified electrode monitored by electrochemical quartz crystal micro-balance. J. Chin. Chem. Soc. 46,115-119. 

In this work, a silane-derivatized dithiocarbamate iniferter was utilized to prepare PMAA brushes on Si/Si02 surfaces under UV irradiation. The combination of the photoiniferter-mediated photopolymerization with a UV-LED source appears to be ideally suited to the direct preparation of polyelectrolyte brushes with minimal free polymer formation during brash synthesis. Following characterization of the PMAA brushes by means of surface-analytical techniques, such as quartz crystal micro-balance with dissipation monitoring (QCM-D), spectroscopic ellipsometry, and static contact-angle measurements, the PMAA brushes were demonstrated to enhance aqueous lubrication of Si/ Si02 under low-contact-pressure conditions. 

Figure 8.5 Quartz crystal micro balance design.

Vikinge TP, et al. Comparison of surface plasmon resonance and quartz crystal micro-balance in the smdy of whole blood and plasma coagulation. Biosens Bioelectron 2000 15 605-13. 

It is worth mentioning that corrosion processes can be investigated in more detail by the use of the electrochemical quartz crystal micro balance (EQCM) [291, 292). Mass changes on the electrode result in very sensitive changes in the resonance frequency of the quartz crystal. Increase of mass, for example, passivation by LiPF or LiDFOB, results in frequency decrease (see Figure 17.8b), whereas corrosion of the surface due to LiOTf is accompanied by mass decrease and a strong frequency increase (see Figure 17.9b) [243]. 

Gahai R, SaUacan N, Chegel V, Bourenko T, Katz E, WiUner I. Characterization of the swelling of acrylamidophenylboronic acid-acrylamide hydrogels upon interaction with glucose by Faradaic impedance spectroscopy, chronopotentiometry, quartz-crystal micro-balance (QCM), and surface plasmon resonance (SPR) experiments. J Phys Chem B 2001 105 8196-8202. 

Jia K, Adam PM, lonescu RE (2013) Sequential acoustic detection of atrazine herbicide and carbofuran insecticide using a single micro-structured gold quartz crystal micro balance. SensOT Actuator B 188 400-404... 

Liang C, Yuan C-Y, Warmack RJ, Barnes CE, Dai S (2(X)2) Ionic liquids a new class of sensing materials for detection of organic vapors based on the use of a quartz crystal micro-balance. Anal Chem 74(9) 2172-2176. doi 10.1021/ac011007h... 

The growth may be examined by the evaluation of electrochemical currents and charges taking into account the corrosion current density as described above. Other methods are based on the application of in situ ellipsometry or electrochemical quartz crystal micro-balance or of surface analytical methods working in UHV like XPS, AES, ISS, and RBS, sometimes in combination with sputter depth profiling. Examples are given in the following section. 

Inertia is the QCM experimenter s best friend. In many wa, QCM experiments come down to the measurement of an (oscillatory) force. One may even spell out "QCM" as "quartz crystal micro- (force) balance." In contrast to AFM, force calibration is close to trivial in... 

Metal-solution interface, quantum mechanical calculations for (Kripsonsov), 174 Metal-water affinity, 177 Micro-balance, quartz crystal, 578 Microwave circuit, 446 for Faraday rotation, 454 Microwave conductivity... 

An application of an electrochemical quartz crystal microbalance (EQCM) in the study of the A11/HCIO4 system shows that even at a potential about 0.5 V more negative than the onset of AuO formation (the so-called preoxide region), the resonant frequency of the Au-covered quartz crystal decreases as that of the surface mass increases. A comparison of a voltammogram with the potential dependence of the micro-balance frequency for an Au electrode is shown in Figs. 6a and 6b. 

Fig. 8.10 Mode of operation of the quartz micro balance (left schematic). Right A dendrimer as guest-selective host compound (selector) for coating of the quartz crystal oscillator. Red Selector layer green various analyte components...

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