Four kinds of deep eutectic solvents (DESs) based on choline chloride (ChCl) with ethylene glycol (EG), malonic acid (MA), urea, and thiourea as hydrogen bond donors were prepared and characterized. All these DESs show good thermal stability and can be stable at 363 K, which is beneficial for the application in flue gas desulfurization. Then, SO 2 absorption capacities of these DESs were determined at different temperatures and SO 2 partial pressures. The absorption results demonstrate that ChCl−EG (1:2) and ChCl−thiourea (1:1) DESs exhibit excellent absorption performances, and the absorption capacities are 2.88 and 2.96 mol SO 2 per mol DES at 293 K and 1 atm, respectively. In addition, the SO 2 absorption and regeneration experiments were conducted. All solvents can be regenerated at 343 K with N 2 bubbling, and the absorption capacities of DESs remain without a significant loss after six absorption and desorption cycles. What's more, the absorption mechanism of SO 2 in these DESs were investigated by IR and 1 H NMR.

Solubilities of SO 2 in ethylene glycol derivatives were determined by dynamic isothermal gas-liquid equilibrium (GLE) experiments, and the thermodynamic parameters of the absorption processes were calculated. The GLE results indicated that the solubilities of SO 2 in ethylene glycol derivatives increase in the order: diols < monomethyl ethers < dimethyl ethers, with the enthalpy values ranging from À23.2 to À43.3 kJ mol À1 . The regeneration experiment found that the absorption of SO 2 in tetraethylene glycol dimethyl ether is reversible, and the solvents can be reused without a significant loss of absorption capacity. The interactions between SO 2 and ethylene glycol derivatives were investigated by UV, IR and NMR. In addition, a 1 H-NMR spectroscopy technique with external references was used to investigate the physical absorption process of SO 2 for the first time, in order to avoid the influence of deuterated solvents. Spectroscopic investigations showed that the interactions between SO 2 and ethylene glycol derivatives are based on both the charge-transfer interaction and hydrogen bond. Ethylene glycol derivatives with desirable absorption capacities and excellent regeneration abilities are promising alternatives to conventional sorbents in SO 2 separation.

Nanoclusters of rocksalt TiO, anatase TiO 2 , and rutile TiO 2 were produced by cluster deposition and examined with transmission-electron microscopy, x-ray diffraction, and magnetization measurements. The clusters are all magnetic at room temperature, but the magnetization is structuredependent. The hysteresis loops show coercivities that are of the order of 100 Oe and all films show a preferential in-plane magnetization direction. The size dependence of the magnetization was investigated for rutile clusters with average sizes from about 15 to 40 nm. The analysis of the measurements indicates that the magnetism is predominantly located near the surface of the clusters and characterized by a nominal value of 7.6 B / nm 2 .

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A sputtering gas-aggregation technique has been used to prepare FePt and FePt:Ag nanocluster films. The cluster size was controlled in a range from 3 to 6 nm. FePt cluster films were directly deposited onto Si substrate; FePt:Ag cluster films were fabricated by depositing a FePt cluster layer between a Ag underlayer and overlayer. Nanostructure and magnetic properties of the samples were characterized by x-ray diffraction, transmission electron microscopy, and magnetometry. The high magnetic anisotropy L1 0 fct phase was realized in the films annealed at a temperature of 550°C and above. The orientation of clusters is random. The coercivity increases with an increase of annealing temperature; high in-plane and out-of-plane coercivities, exceeding 10 kOe, were achieved in both FePt and FePt:Ag cluster films after annealing. For FePt:Ag films, the coercivity increases with Ag underlayer thickness, t Ag , and reaches about 17 kOe at room temperature for t Ag ϭ5 nm after annealing at 650°C for 10 min. The high coercivity is closely correlated with the degree of L1 0 ordering and nanostructure of the films.

-energy product exchange-spring FePt/Fe cluster nanocomposite permanent magnets" (2006). David Sellmyer Publications. 95.

In this letter, the authors demonstrate isotropic Fe–Pt exchange-spring nanocomposite permanent magnets with a soft magnetic phase fraction of greater than 0.5 with a coercivity of 6.5kOe, single-phase-like magnetic behavior, and an energy product of 25.1MGOe. Sub-10-nm Fe–Pt clusters are formed with compositions in the two-phase Fe3Pt and FePt regions. Intracluster structuring on a scale of a few nanometers occurs after appropriate heat treatment. This ensures full exchange coupling between the two phases, allowing greater soft magnetic phase fractions. The results provide insight into developing high energy product nanostructured permanent magnets.

To optimize the structure of the flexible piezoresistive sensor based on conductive polymer composite and widen the workable pressure range, a piezoresistive sensor with a multilayered structure based on carbon nanotubes/carbon black/silicone rubber conductive composite was designed and investigated. Different from the traditional monolayer structure, this novel multilayered sensor consisted of three microstructured piezoresistive composite films. The experimental data showed that the electrical resistance of the sensor varied regularly with a wide range of applied pressure (0-1.8 MPa at least). The high sensitivity, high flexibility, facile fabrication, and low cost were also the advantages of this pressure sensor. In addition, the piezoresistive mechanism was studied and shown to be the synergistic effects of the contact resistance mechanism and bulk resistance mechanism. Factors influencing the piezoresistive properties were also investigated. Moreover, the consecutive loading tests verified the feasibility and stability to use this sensor element for pressure measurement.