High quality LiCoO 2 crystals, useful as cathode material for lithium-ion rechargeable batteries, were successfully grown at a holding temperature of 800-1000 °C using the NaCl flux cooling method. The morphology, structure, size uniformity, and crystallinity of the obtained LiCoO 2 crystals were obviously dependent on the growth conditions, such as the holding temperature and the starting composition. Well-developed, highly crystalline LiCoO 2 crystals were first grown at a holding temperature of 900 °C from a NaCl flux. The grown LiCoO 2 crystals had a hexagonal barrel-shaped structure with welldeveloped {001}, {104}, {101}, and {102} faces. On the basis of the powder X-ray diffraction data, the lattice parameters of the crystals were determined as a = 2.816 and c = 14.077 A ˚. These values agree approximately with those from the literature (a = 2.816 and c = 14.052 A ˚). The average crystal size was about 1.4 μm, which is a relatively small size when compared to previous reports. Transmission electron microscopy images indicate that the LiCoO 2 crystals were of very good crystallinity. It was confirmed that the charge and discharge capacities of the lithium-ion rechargeable batteries containing the grown LiCoO 2 crystals were 138 and 130 mAh 3 g -1 , respectively, values that correspond to the available capacity of 137.5 mAh 3 g -1 . The discharge capacity of the grown LiCoO 2 crystal is greater at 10 C than that of commercially available crystals.

Alkyl organic monolayers with different alkyl molecular chain lengths directly attached to silicon were prepared at 160 degrees C from 1-decene (C10), 1-dodecene (C12), 1-tetradecene (C14), 1-hexadecene (C16), and 1-octadecene (C18). These monolayers were characterized on the basis of water contact angle measurement, ellipsometry, X-ray reflectivity (XR), X-ray photoelectron spectroscopy (XPS), and grazing incidence X-ray diffraction (GIXD) to elucidate the effect of the molecular chain length on the molecular arrangement and packing density of the monolayers. Water contact angle and XPS measurements showed that C12, C14, and C16 monolayers have a comparably higher quality, while the quality of C10 and C18 monolayers is worse. GIXD revealed that the alkyl monolayers directly attached to the Si were all amorphously structured regardless of their alkyl chain length. The amorphous structure of the alkyl monolayers could be attributed to the rigid Si-C bonding, low quality of hydrogen-terminated silicon substrate, and/or low mobility of physisorbed molecules.

Highly crystalline, NaYF4 and NaYF4:Ln (Ln = Yb, Er, Tm) crystals with upconversion fluorescence were successfully grown by the cooling of the solo NaF flux at a holding temperature of 1100 °C and cooling rate of 5 °C·h−1. The basic forms of NaYF4 and NaYF4:Ln crystals were a sphere. The crystal system, form, and size were affected by cooling rate. The red, green, and blue upconversion fluorescence of NaYF4:Ln crystals were clearly observed under 980 nm laser irradiation by a two- or three-photon upconversion process. The upconversion fluorescence of NaYF4:Ln crystals was successfully controlled by changing the cooling rate and type of dopant. Furthermore, the NaYF4:Yb,Er crystals were successfully grown using a mixed NaF-KF flux cooling method at a relatively low temperature of 800 °C.

The antioxidant, anti-inflammatory and antibacterial activities of hesperetin, hesperidin and hesperidin glucoside with different solubility were compared in vitro. Hesperetin was prepared by enzymatic hydrolysis from hesperidin, and hesperidin glucoside composed of hesperidin mono-glucoside was prepared from hesperidin through enzymatic transglycosylation. Solubility of the compounds was different: the partition coefficient (log P) was 2.85 ± 0.02 for hesperetin, 2.01 ± 0.02 for hesperidin, and −3.04 ± 0.03 for hesperidin glucoside. Hesperetin showed a higher effect than hesperidin and hesperidin glucoside on radical scavenging activity in antioxidant assays, while hesperidin and hesperidin glucoside showed similar activity. Cytotoxicity was low in the order of hesperidin glucoside, hesperidin, and hesperetin in murine macrophage RAW264.7 cells. Treatment of the cells with each compound reduced the levels of inflammatory mediators, nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6). Hesperetin was most effective at relatively low concentrations, however, hesperidin glucoside was also effective at higher concentration. Hesperetin showed higher antibacterial activity than hesperidin in both Gram-positive and -negative bacteria, and hesperidin glucoside showed similarly higher activity with hesperetin depending on the bacterial strain. In conclusion, hesperetin in the form of aglycone showed more potent biological activity than hesperidin and hesperidin glucoside. However, hesperidin glucoside, the highly soluble form, has been shown to increase the activity compared to poorly soluble hesperidin.

Unique and characteristically formed spherulitic crystals of octacalcium phosphate (OCP, Ca8H2(PO4)6·5H2O) were grown for the first time by the gel method, using the system Ca(NO3)2−(NH4)2HPO4−agar. The shape of test tubes crucially affected the morphological development of the OCP crystals. The feature of OCP spherulites grown in U-type test tubes was an aggregation of a relatively ordered, large number of ultralong and flexible whiskers radiating from the center region of the spheres, resulting in high porosity. On the other hand, OCP crystals grown in straight test tubes were a spherulite consisting of a large number of short plate-like, well-faceted crystallites radiating from a common origin. In both cases, OCP crystals grew with spherulitic morphologies even under varied conditions of different growth parameters, including gel concentration, reactant concentration, and growth period.

Highly crystalline niobium oxide (Nb 2 O 5 ) nanotubes without defects such as bent and node were successfully prepared by a two-step process. The first step entails making high quality, layered K 4 Nb 6 O 17 crystals as a precursor material. In this study, well-developed, highly crystalline, layered K 4 Nb 6 O 17 crystals were readily grown by the rapid cooling of a KCl flux at a holding temperature of 800 C and a cooling rate of 300 C h À1 . The grown layered crystals of K 4 Nb 6 O 17 were transparentcolorless and had a median diameter of 530 nm. They were plate-like with well-developed faces. The second step is to transform the layered K 4 Nb 6 O 17 crystals into highly crystalline Nb 2 O 5 nanotubes. In order to make the nanotubes, an intercalation-exfoliation process using tetra(n-butyl)ammonium hydroxide (TBA + OH À ) aqueous solution was carried out, and highly crystalline Nb 2 O 5 nanotubes having a uniform diameter were successfully fabricated in this medhod. The crystallinity, uniformity and size (diameter and length) of nanotubes were significantly dependent on those of the precursor crystals. The flux-grown crystals, therefore, played a very important role in the nanotube fabrication. The average length and outer diameter were, respectively, about 100-500 nm and 15-25 nm. The photocatalytic properties of the layered K 4 Nb 6 O 17 crystals and the Nb 2 O 5 nanotubes were basically almost the same, although their Brunauer-Emmett-Teller (BET) surface areas were quite different from each other. The BET surface area of the Nb 2 O 5 nanotubes (108.71 m 2 g À1 ) was ca 20 times larger than that of the layered K 4 Nb 6 O 17 crystals (5.14 m 2 g À1 ). As compared with the flux-grown K 4 Nb 6 O 17 crystals, the Nb 2 O 5 nanotubes exhibited high photocatalytic activity for the photodegradation of trichloroethylene. The grown layered K 4 Nb 6 O 17 crystals and Nb 2 O 5 nanotubes were investigated thoroughly by means of field emission scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction analysis, energy-dispersive X-ray spectrometry, BET surface area and pore size distribution analysis, and spectrophotometry.

Highly ordered, macropore arrays, that is, inverse opal structures, of Na2W4O13 were successfully synthesized by spray pyrolysis using polystyrene (PS) colloidal crystals as templates. A densely packed monolayer of monodisperse PS microspheres was deposited on a silica glass substrate by use of the Langmuir-Blodgett thin film technique. Subsequently, Na2W4O13 layers were deposited on the PS templates as a thin layer by spray pyrolysis of a 5(NH4)2O.12WO(3).5H2O-NaCl solution. The PS templates were, finally, removed by thermal treatment, generating a surface with features (inverse opal structures) located where the interstitial space of the densely hexagonal-packed PS microspheres had been. The macroporous structures obviously depended on the annealing conditions such as time and temperature. The macropores were basically hemispherical in shape and highly honeycombed arrangement, which corresponded well to the PS templates. The inverse opal textures of Na2W4O13 layer surfaces enhanced their hydrophobicity. The surfaces modified by fluoroalkylsilane (FAS) were converted from hydrophobic (water contact angle=127 degrees) to hydrophilic (30 degrees) by photocatalytic oxidation using the Na2W4O13 crystal layer. The Na2W4O13 crystals exhibited high activity for FAS photodegradation.

Highly crystalline upconversion fluorescence crystals of ytterbium phosphate (YbPO 4 ) doped with Er 3þ or Tm 3þ were selectively and directly grown on a hydrophilic/hydrophobic self-assembled monolayer (SAM) template patterned by vacuum ultraviolet (VUV, λ = 172 nm) light irradiation. First, a gelatin gel with an inner solution [(NH 4 ) 2 HPO 4 ] was selectively adsorbed on a hydrophilic surface, and the adsorbed gel was successfully used as the micro reaction cell between the inner solution and the outer solution [(CH 3 COO) 3 Yb 3 4H 2 O]. The low crystalline YbPO 4 :Ln (Ln = Er or Tm) nanospheres, which are densely aggregated, were selectively and directly grown on the hydrophilic surface at 5 °C for 5 days. After annealing at 1100 °C for 10 h, their shape changed dramatically from an aggregation of nanospheres to an aggregation of well-formed nanocubes (200-600 nm). In addition, atoms and molecules of Yb, PO 4 , and Ln were highly and uniformly distributed in the YbPO 4 :Ln crystal. The YbPO 4 :Er and YbPO 4 :Tm crystals clearly show green and blue upconversion fluorescence, respectively, under 980 nm (near-infrared) laser irradiation.