The rhizomes of the Zingiberaceae family are a vegetable widely used in many Asian countries, and their medicinal functions have been broadly discussed and accepted in many traditional recipes. In this study, 18 species of five genus of Zingiberaceae plants from Taiwan area were collected and analyzed for their functional properties. Methanolic extracts of the plants were analyzed for their total phenol compounds, alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) scavenging activity, and reducing power. Antimicrobial activity of these samples was also determined. The results showed that the total phenol compounds of the Alpinia genus averaged 17, 30 mg/g for Curcumas, and the highest, 36.5 mg/g for Vanoverberghia sasakiana. Antioxidant performances were best observed in Vanoverberghia and Hedychium, both 89%, and DPPH scavenging activity followed similar trends. Particularly, Zingiber oligophyllum, considered as a traditional medicinal plant used in Taiwan exhibited low DPPH scavenging activity and reducing power. Most Zingiberaceae plant extracts exhibited antimicrobial activity against all tested food microorganisms. Hedychium and Vanoverberghia, did not show antimicrobial activities on Escherichia coli and Vibrio parahaemolyticus. This study is a positive demonstration of the utility of screening Taiwan's endemic Zingiberaceous plants for their food and medicinal uses.

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The present study evaluated functional properties of lactic-fermented ginger products. Three Zingiberaceae species were used as the substrate for fermentation using three lactic acid bacteria. The fermentation process ended 35-40 h after inoculation and reached a pH value of 3.5-4.0. Total antioxidant performances were 68-75%, and were best observed using Bifidobacterium longum as the starter in three ginger samples. DPPH scavenging was on average 70%, with free radical anion scavenging and peroxide removal effects of 30.6% and 43.7%, respectively. The product acceptance survey showed that the 100% fermented juice without a mixture with non-fermented ginger juice obtained the highest score in overall performance. The lactic-fermented Vanoverberghia and Hedychium ginger species retained an antioxidant activity and DPPH scavenging activity of on average 70%. This study may suggest a new way of ginger food processing with high functionality. Also, it may help to popularize the growing and processing of endemic ginger plants in Taiwan.

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Phase‐change memory materials such as the pseudobinary GeTe‐Sb2Te3 compounds have recently gained attention for their good thermoelectric properties, which can be used for power‐generation/cooling applications. In this work, GeTe‐rich Ge–Sb–Te thin films deposited using a radio‐frequency magnetron sputtering method readily exhibit the metastable face‐centered cubic (FCC) phase at room temperature. This is in stark contrast to its bulk form, which only transforms to its FCC phase after a transition temperature of around 350 °C. Based on previous works, the FCC phase contributes to the superior thermoelectric properties of this material system. In this study, by decreasing the working deposition pressure, the preferred orientation of (200) plane is observed that translates to improved carrier mobility. Moreover, increasing the annealing temperature has been shown to decrease the carrier concentration due to Te deficiency, leading to a significant improvement in the Seebeck coefficient of the film. By combining these effects, an optimized thermoelectric power factor (21 μW/cm K2) was obtained at an operating temperature of 350 °C.

Magnetotransport measurements of PtPb4 single crystals with the T c of ∼2.80 K reveal pronounced exotic topological nature. An anomalous negative longitudinal magnetoresistance (MR) related to the chiral anomaly and a linear-like transverse MR examined within the framework of quantum MR theory were studied. Results indicate the presence of chiral-anomaly-induced quantum transport associated with the Weyl states and show a Dirac-cone-like band dispersion in PtPb4. This work reveals the drastic impact of the concept that the surface electrons in a Weyl fermion state may dominate the normal-state magnetotransport in PtPb4, leading to the conclusion that PtPb4 can be a Weyl-semimetal superconductor candidate.

Magnetotransport properties with a large positive magnetoresistance (MR) and a high carrier mobility for applications have been achieved and probed for quenched Fe 0.01 Bi 2 Te 3 single crystals. Large positive MR of ∼470% with a Hall mobility of ∼44 000 cm 2 V −1 s −1 at 5 K and 6 T has been observed on a quenched Fe 0.01 Bi 2 Te 3 sample, in which the electrical parameters can be tuned by the quenching temperature T q . The MR behaviors for the quenched samples show a crossover from a weak antilocalization-dominant MR to a linear and non-saturating MR at temperatures of T * ≈58−100 K, where the large MR at low temperatures possibly originates from the mechanism of topologically protected backscattering. On the contrary, the MR behaviors for the strain-released sample do not show such a distinct crossover, where only linear-like and non-saturating MR behaviors can be observed. Different electrical transports between the quenched and strain-released samples indicate that the band structure, as well as the surface Dirac electrons in Fe 0.01 Bi 2 Te 3 , can be modified by the lattice strain. Furthermore, it is found that the low-temperature magnetoconductivity can be well described by the weak-antilocalization transport formula, while the high-field linear-like MR at T>T * can be explained in terms of Abrikosov's quantum transport of Dirac-cone states in quenched Fe 0.01 Bi 2 Te 3 single crystals.

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