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Analytical Applications of Piezoelectric Crystal Biosensors
Published in Loïc J. Blum, Pierre R. Coulet, Biosensor Principles and Applications, 2019
John H. T. Luong, George G. Guilbault
The principle piezoelectric materials used commercially are crystalline quartz and Rochelle salt, despite the existence of a wide range of other materials, such as tourmaline, ammonium dihydrogen phosphate, ethylenediamine tartrate, and barium titanate. Rochelle salt possesses a large piezoelectric effect, and this material is useful in acoustical and vibrational devices in which sensitivity is desired. However, it decomposes at only 55°C and requires protection against moisture. Barium titanate has lower sensitivity but greater immunity to temperature and humidity effects. Quartz has the important quality of being a completely oxidized compound (silicon dioxide). It is insoluble in water and resists temperatures of up to 579°C with no loss of piezoelectric properties. Industrially grown rather than natural quartz crystals are used almost exclusively for electro-gravimetric sensors because of their higher purity, and a quartz is most often used.
A Survey of Medical Imaging Systems
Published in Robert B. Northrop, Non-Invasive Instrumentation and Measurement in Medical Diagnosis, 2017
Early piezoelectric transducers were naturally occurring materials such as used in World War II sonar systems, such as quartz, Rochelle salt (NaKC4H4O6 · 4H2O = sodium potassium tartrate), or ammonium dihydrogen phosphate (NH4H2PO4 = ADP). The first synthetic, piezoceramic material was barium titanate (BaTiO3). Synthetic, ferroelectric, piezoceramics are not naturally piezoelectric; they must be poled by exposing them to a very strong internal electric field (∼20 kV/cm) as they cure. There are now many different piezoceramics; for example, many formulations of lead zirconate titanate (PZT, Pb(Zr, Ti)O3), lead zirconate, lithium metaniobate (LiNbO3), and lead metaniobate (PbNb2O6). One advantage to the use of piezoceramics is that they can be made in any desired shape to suit the application (disks, rods, bars, hollow cylinders, half-cylinders, hollow spheres, hemispheres, etc.).
Electronic materials for transducers: sensors and actuators
Published in David Jiles, Introduction to the Electronic Properties of Materials, 2017
The most common forms of transducer materials are piezoelectric, electrostrictive and magnetostrictive materials. Piezoelectric/electrostrictive transducer materials include quartz, ammonium dihydrogen phosphate, tourmaline, lithium sulphate, barium titanate, lead zirconate and lead magnesium niobate, and Rochelle salt (potassium sodium tartrate tetrahydrate, KNaC4H406.4H20). Magnetostrictive transducer materials include nickel alloys and some of the more recent rare earth-iron alloys such as Terfenol (terbium-dysprosium-iron).
Optimization of operating conditions in purification of wet process phosphoric acid in a liquid-liquid extraction column
Published in Chemical Engineering Communications, 2022
Mohammad Daryani, Naeimeh Jodeiri, Esmaeil Fatehifar, Javad Shahbazi
Experimental results of previous researches indicate the desirability of this method for minimizing the impurities and improving the efficiency of acid or extraction (Mishra et al. 2011; Li et al. 2017b). In a study that has been carried out by solvent extraction method, the combination of cyclohexanol with kerosene has been applied (Li et al. 2017b), and the effect of the time, initial concentration of phosphoric acid, temperature, the concentration of cyclohexanol and organic to aqueous phase ratio was investigated. In this work, the behavior of impurity separation factor and acid extraction level based on parameter level change has been studied and the results showed that it takes almost 10 min to attain extract equilibrium. removal from ammonium dihydrogen phosphate solution by solvent extraction with 2-ethylhexyl phosphoric acid has been studied, and high removal rate for the impurity was achieved (Luo et al. 2011). The purification of WPPA by methyl isobutyl ketone solvent has been studied extensively (Feki et al. 2002). The tributylphosphate solvent has been highly regarded and suggested because of its selectivity and low solubility in water. Phosphate also improves the acid content (Hannachi et al. 2007).
The disappearance of photocatalytic properties of titanium dioxide nanoparticles formed on PET fabrics treated in a simultaneous hydrothermal-dyeing process
Published in The Journal of The Textile Institute, 2018
Hui Zhang, Haijun Xue, Ningtao Mao
The gray PET fabric was friendly provided by the Northwest No.5 Textile Mill. The linear densities of both warp and weft yarns were identical (12.3 tex). The yarn densities in warp and weft directions were 113 and 88 ends per 10 cm, respectively. The fabric mass per unit area was 115 gram per square meter. The chemical agents used in this experiment were all analytical reagent grade, including sodium hydroxide (NaOH), ammonium dihydrogen phosphate (NH4H2PO4), ethanol (CH3CH2OH), acetone (CH3COCH3), sodium carbonate (NaCO3), tetrabutyl titanate (C16H36O4Ti), methyl orange (MO, C14H15N3NaO3S) dye. The Disperse Blue 79 (CAS No.12239-34-8, C24H27BrN6O10) dye and dispersing agent NNO (CAS No.36290-04-7, C21H14Na2O6S2) were obtained from a local printing and dyeing mill. The deionized water was used throughout this experiment.
Purification, biochemical, and thermal properties of fibrinolytic enzyme secreted by Bacillus cereus SRM-001
Published in Preparative Biochemistry and Biotechnology, 2018
Manoj Kumar Narasimhan, Selvarajan Ethiraj, Tamilarasan Krishnamurthi, Mathur Rajesh
Vegetative spores of B. cereus SRM-001 preserved in glycerol slants were inoculated into 100 mL seed media consisting of 1.9% soybean powder, 0.3% corn flour, and 11.2 mM MnSO4 and incubated in a shaker at 150 rpm and 37°C for 24 h. A 1% seed inoculum was transferred into fermentation medium consisting of 2% ammonium dihydrogen phosphate (NH4H2PO4), 0.5% sucrose, 1% yeast extract, and 11.2 mM MnSO4 at pH 7 and allowed to incubate in a shaker at 150 rpm for 24 h at 37°C. The fermented media were centrifuged at 10,000 rpm for 10 min to recover the crude enzyme bearing supernatant and subjected to purification. A spectrophotometric assay was used to determine the FEA and estimate the protein content by Lowry’s method, respectively, in the process.[31,32]