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Olivine-type Li rich Li1+xFePO4/C composites are synthesized by a solid state reaction process using premilled Li2CO3 and pre-synthesized amorphous FePO4·xH2O powders. The amorphous FePO4·xH2O powders are prepared from an industrial waste liquid (by-product), a FeCl3 (38%) solution, via a precipitation process. In addition, lithium carbonate is pre-milled using a high energy nano mill to control particle sizes and shape differences for enhancing the reaction activity in the starting materials. The main purpose of this study is to investigate the effect of excess Li on the electrochemical properties of LiFePO4 cathode materials. The pre-synthesized FePO4 powders are mixed with pre-milled lithium carbonate and glucose (8 wt%) using a ball-mill process. The structural characteristics of the Li1+xFePO4/C composites are examined by XRD and SEM. To investigate the effect of excess Li content on the electrochemical properties in Li1+xFePO4/C composites, a Li[LiPF6 (Ethylene carbonate + Dimethyl carbonate)] Li1+xFePO4/C model cell is used. It is demonstrated that the 1% Li rich Li/[Li1.01FePO4/C] cell exhibits the best electrochemical performance and delivers an initial discharge capacity of 161 mAhg−1, which is 25 mAhg−1 higher than that of the Li/[LiFePO4/C] cell.

Olivine-type LiFePO4/C cathode materials are fabricated with FePO4 powders that are pre-synthesized by two different processes from iron chloride solution. Process I is a modified precipitation method which is implemented by the pH control of a solution using NH4OH to form FePO4 precipitates at room temperature. Process II is a conventional precipitation method, of which H3PO4 (85%) solution is gradually added to a FeCl3 solution during the process to maintain a designated mole ratio. The solution is subsequently aged at 90°C in a water bath until FePO4 precipitates appear. In order to synthesize LiFePO4/C composites, each batch of FePO4 powders is then mixed with pre-milled lithium carbonate and glucose (8 wt. %) as a carbon source in a ball-mill. The structural characteristics of both LiFePO4/C composites fabricated using iron phospates from two different routes have been examined employing XRD and SEM. The modified precipitation process is considered to be a relatively simple and effective process for the preparation of LiFePO4/C composites owing to their excellent electrochemical properties and rate capabilities.

This paper presents original results obtained in the development of dome-shaped actuator for a linear motor application. The main structure of compact ultrasonic linear motor presented in this paper consists of three parts, which were an actuating part, a shaft and mobile element. The actuating part was fabricated by powder injection molding (PIM) process. The linear motion of new-type linear motor was operated by the principle of inertia displacement. The actuating part combined with clamping ceramic element can be realized by the central movement of dome-shaped piezoelectric actuator (DSPA), which has the maximum displacement of the up-and-down movement. The linear motor, where DSPA was 9.86 mm in diameter, 4.6 mm in curvature of radius and 0.4 mm in thickness, operated at 1st resonance frequency. The dynamic characteristics of the motor was investigated by finite element method (FEM) and compared with experimental results. These results were in good agreement with that predicted by simulations.

This work was to investigate the effect of flavonoids from Angelica gigas Nakai on the proliferation and differentiation of PC12 cells. Several solvents including hexane, chloroform, ethyl acetate, butanol and water consecutively partitioned. We determined the ethanol crude extract of Angelica gigas Nakai. The hexane fraction was shown to contain the highest number of flavonoids as follows; 21.48 mg/g and the composition of the flavonoids was as follows: 12.24 mg/g of quercetin, 4.39 mg/g of myricetin and 2.58 mg/g of catechin. In addition, this hexane fraction greatly increased both cell growth and outgrowth of the neurite, and whose effects were three times higher than those of the other fractions. The length of the neurites was measured as ca. 110 μm in adding 50 μg/mL of the hexane fraction, which was about the same as the case of adding 50 ng/mL of NGF as a positive control. This result indicates that the differentiation of PC12 cells by the addition of the hexane fraction was comparable to the case of adding NGF. The hexane fraction was also determined to prevent apoptosis of PC12 cells by suppressing DNA fragmentation. It is interesting that the mixture of three major flavonoids, quercetin, myricetin and catechin showed stronger activity on, both PC12 cell growth and neuritis outgrowth, than when adding each flavonoid alone. We believe this was due to the synergistic effects of the three flavonoids. The activities of these flavonoids from Angelica gigas Nakai are reported for the first time in this study.

Targeted mRNA degradation by short interfering RNAs (siRNAs) offers a great potential to treat cancers. siRNA therapeutics for leukemias are, however, hindered by poor intracellular uptake, limited blood stability and nonspecific delivery. To solve these problems, we developed an anti-JL1 immunonanoplex (antibody-coupled nanocomplex) for siRNA delivery using anti-JL1 minibody (leukemia cell-specific minibody) conjugated to oligo-9-Arg peptide (9R) for effective siRNA delivery to leukemic cells. The anti-JL1 immunonanoplexes were able to deliver siRNA specifically to leukemic cells (CEM and Jurkat), but not to control cancer cells (H9). According to FACS and confocal microscopic analysis, siRNAs delivered by immunonanoplex particles were rapidly taken up by the JL1-positive cancer cells in 2 h. Furthermore, we showed that the anti-JL1 immunonanoplexes were effectively targeted to JL1-positive cells (CEM) inoculated in the mouse bone marrow. These results suggest that the anti-JL1 immunonanoplex is a powerful siRNA delivery system for human leukemia therapies.

The piezoelectric properties of (1−x)(Bi0.5Na0.5)TiO3-xBaTiO3 ceramics were reported and their piezoelectric properties reach extreme values near the MPB (about x = 0.06). The X-ray analysis of (Bi0.5Na0.5)0.94Ba0.06TiO3 ceramics for all compositions exhibited a pure perovskite structure without any secondary phase. Within a certain ratio of contents, the co-doped ceramics enhanced piezoelectric coefficient (d 33 ), lowered the dielectric loss, and increased the sintered density. The temperature dependence of relative dielectric permittivity (K 33 T ) reveals that the solid solutions experience two phase transitions, ferroelectric to anti-ferroelectric and anti-ferroelectric to relaxor ferroelectric, which can be proven by P-E hysteresis loops at different temperatures. In addition, the specimen containing 0.04/0.01 wt.% CaO/MnO showed that the coercive field E c was a minimum value of 26.7 kV/cm, while the remnant polarization P r was a maximum value of 38.7 μC/cm2, corresponding to the enhancement of piezoelectric constant d33 of 179 pC/N, electromechanical coupling factor k p of 37.3%, and relative dielectric permittivity K 33 T of 1137. (Bi0.5Na0.5)0.94Ba0.06TiO3 ceramics co-doped with CaO/MnO were considered to be a new and promising candidate for lead-free piezoelectric ceramics owing to their excellent piezoelectric/dielectric properties, which are superior to an un-doped BNBT system.

This paper describes micromachined piezoelectric microspeakers that can produce an audible signal supplied from an MP3 player through the use of 5Vpeak-to-peak signal amplification circuit modules. The Sound Pressure Level (SPL) of the fabricated microspeakers is higher than that of previous results even though the input voltage is reduced. The success of this technology is based upon two distinct features; one is the use of a high quality compressive ZnO thin film, the other is the implementation of a floating electrode beneath the piezoelectric ZnO film in order to induce more strain in the diaphragm of the microspeaker when two top electrodes are biased with different polarities. A high quality piezoelectric ZnO film is achieved using an Ar/O2 gas ratio of 4:1, an R.F. power of 1,500W, a substrate temperature of 150°C, and a chamber pressure of 23mTorr. In this condition, the deposited ZnO film shows a compressive residual stress of −1.3GPa. The fabricated piezoelectric microspeakers were tested over a frequency range of 400Hz to 12kHz with a 5Vpeak-to-peak input signal, the maximum SPL of the fabricated microspeakers was shown to be more than 97.2dB at 7.1kHz with a distance of 3mm between the fabricated microspeakers and the reference microphone (B&K type 2,669 and 4,192L).

Perovskite-type 0.05 Pb(Mn1/3Sb2/3)O3-0.95 Pb(Zr0.5Ti0.5)O3 (PMS-PZT) was synthesized by conventional bulk ceramic processing technique. ZnO as a dopant up to 0.5 mol% was incorporated into the PMS-PZT system, and the effects on piezoelectric properties were investigated. Pyrochlore phase was not detected to form during the synthesis of the PMS-PZT system with 0∼0.5 mol% ZnO addition. The highest density of 7.92 g/cm3 was obtained when sintered at 1200°C for 2 hrs. Piezoelectric properties as a function of ZnO content were evaluated using a gain phase analyzer. Piezoelectric charge constant (d31) and piezoelectric voltage output coefficient (g31) increased up to −130 pC/N and −24.9 × 103Vm/N, respectively, with increasing ZnO content. Mechanical quality factor (Q m) was shown to reduce considerably with increasing ZnO content. When 0.3 mol% of ZnO was added into the system, electromechanical coupling factor (k p) and relative dielectric constant ( $$ {\varepsilon ^{T}_{{33}} } \mathord{\left/ {\vphantom {{\varepsilon ^{T}_{{33}} } {\varepsilon _{0} }}} \right. \kern-\nulldelimiterspace} {\varepsilon _{0} } $$ ) reached to the maximum of 56% and 1,727, respectively.

Perovskite-types 0.05Pb(Mn1/3Sb2/3)O2-0.95Pb- (Zr0.5Ti0.5)O3 (PMS-PZT) was synthesized by conventional bulk ceramic processing technique. ZnO as a dopant up to 0.5 mol% was incorporated into the PMS-PZT system, and the effects on piezoelectric properties were investigated. Pyrochlore phase was not detected to form during the synthesis of the PMS-PZT system with 0–0.5 mol% ZnO addition. The highest density of 7.92 g/cm3 was obtained when sintered at 1200∘C for 2 h. Piezoelectric properties as a function of ZnO content were evaluated using a gain phase analyzer. Piezoelectric charge constant (d 31) and piezoelectric voltage output coefficient (g 31) increased up to −130 pC/N and −24.9 × 103Vm/N, respectively, with increasing ZnO content. Mechanical quality factor (Q m) was shown to reduce considerably with increasing ZnO content. When 0.3 mol% of ZnO was added into the system, electromechanical coupling factor (k p) and relative dielectric constant (e33 T /eo) reached to the maximum of 56% and 1727, respectively.