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Flexible wearable electronics, when combined with outstanding thermoelectric properties, are promising candidates for future energy harvesting systems. Graphene and its macroscopic assemblies （e.g., graphene-based fibers and films） have thus been the subject of numerous studies because of their extraordinary electrical and mechanical properties. However, these assemblies have not been considered suitable for thermoelectric applications owing to their high intrinsic thermal conductivity. In this study, bromine doping is demonstrated to be an effective method for significantly enhancing the thermoelectric properties of graphene fibers. Doping enhances phonon scattering due to the increased defects and thus decreases the thermal conductivity, while the electrical conductivity and Seebeck coefficient are increased by the Fermi level downshift. As a result, the maximum figure of merit is 2.76 ~ 10~, which is approximately four orders of magnitude larger than that of the undoped fibers throughout the temperature range. Moreover, the room temperature power factor is shown to increase up to 624 btW.m-l.K-2, which is higher than that of any other material solely composed of carbon nanotubes and graphene. The enhanced thermoelectric properties indicate the promising potential for graphene fibers in wearable energy harvesting systems.

In spite of the recent successful demonstrations of flexible and transparent film heaters, most heaters with high optical transmittance and low applied direct current （DC） voltage are silver nanowire （Ag NW）-based or silver grid-based. In this study, flexible and stretchable copper nanowire （Cu NW）-based transparent film heaters were fabricated through a solution-based process, in which a thin layer of hydrophobic polymers was encapsulated on the Cu NW films. The thin polymer layer protected the films from oxidation under harsh testing conditions, i.e., high temperature, high humidity, and acidic and alkaline environments. The films exhibited remarkable performance, a wide operating temperature range （up to 150 ℃）, and a high heating rate （14 ℃/s）. Defrosting and wearable thermotherapy demonstrations of the Cu NW film heaters were carried out to investigate their practicality. The Cu NW-based film heaters have potential as reliable and low-cost film heaters.

The dinoflagellate Noctiluca scintillans is one of the most important and abundant red tide organisms and it is distributed world-wide. It occurs in two forms. Red Noctiluca is heterotrophic and fills the role of one of the microzooplankton grazers in the foodweb. In contrast, green Noctiluca contains a photosynthetic symbiont Pedinomonas noctilucae (a prasinophyte), but it also feeds on other plankton when the food supply is abundant. In this review, we document the global distribution of these two forms and include the first maps of their global distribution. Red Noctiluca occurs widely in the temperate to sub-tropical coastal regions of the world. It occurs over a wide temperature range of about 10°C to 25°C and at higher salinities (generally not in estuaries). It is particularly abundant in high productivity areas such as upwelling or eutrophic areas where diatoms dominate since they are its preferred food source. Green Noctiluca is much more restricted to a temperature range of 25°C–30°C and mainly occurs in tropical waters of Southeast Asia, Bay of Bengal (east coast of India), in the eastern, western and northern Arabian Sea, the Red Sea, and recently it has become very abundant in the Gulf of Oman. Red and green Noctiluca do overlap in their distribution in the eastern, northern and western Arabian Sea with a seasonal shift from green Noctiluca in the cooler winter convective mixing, higher productivity season, to red Noctiluca in the more oligotrophic warmer summer season.

High-purity straight and discrete multiwalled boron nitride nanotubes （BNNTs） were grown via a boron oxide vapor reaction with ammonia using LiNO3 as a promoter. Only a trace amount of boron oxide was detected as an impurity in the BNNTs by energy-dispersive X-ray （EDX） and Raman spectroscopies. Boron oxide vapor was generated from a mixture of B, FeO, and MgO powders heated to 1,150 ℃, and it was transported to the reaction zone by flowing ammonia. Lithium nitrate was applied to the upper side of a BN bar from a water solution. The bar was placed along a temperature gradient zone in a horizontal tubular furnace. BNNTs with average diameters of 30-50 nm were mostly observed in a temperature range of 1,280-1,320 ℃. At higher temperatures, curled polycrystalline BN fibers appeared. Above 1,320 ℃, the number of BNNTs drastically decreased, whereas the quantity and diameter of the fibers increased. The mechanism of BNNT and fiber growth is proposed and discussed.

A facile strategy was designed for the fabrication of Fe3O4-nanoparticle- decorated TiO2 nanofiber hierarchical heterostructures （FTHs） by combining the versatility of the electrospinning technique and the hydrothermal growth method. The hierarchical architecture of Fe3O4 nanoparticles decorated on TiO2 nanofibers enables the successful integration of the binary composite into batteries to address structural stability and low capacity. In the resulting unique architecture of FTHs, the 1D heterostructures relieve the strain caused by severe volume changes of Fe3O4 during numerous charge-discharge cycles, and thus suppress the degradation of the electrode material. As a result, FTHs show excellent performance including higher reversible capacity, excellent cycle life, and good rate performance over a wide temperature range owing to the synergistic effect of the binary composition of TiO2 and Fe304 and the unique features of the hierarchical nanofibers.

Hot deformation behavior of the Cu-Cr-Zr alloy was investigated using hot compressive tests in the tem- perature range of 650-850℃ and strain rate range of 0.001-10 s-1. The constitutive equation of the alloy based on the hyperbolic-sine equation was established to characterize the flow stress as a function of strain rate and deformation temperature. The critical conditions for the occurrence of dynamic recrystallization were determined based on the alloy strain hardening rate curves. Based on the dynamic material model, the processing maps at the strains of 0.3, 0.4 and 0.5 were obtained. When the true strain was 0.5, greater power dissipation efficiency was observed at 800-850 ℃ and under 0.001-0.1 s-1, with the peak efficiency of 47%. The evolution of DRX microstructure strongly depends on the deformation temperature and the strain rate. Based on the processing maps and microstructure evolution, the optimal hot working conditions for the Cu-Cr-Zr alloy are in the temperature range of 800-850 ℃ and the strain rate range of 0.001-0.1 s-1.

The hot deformation behavior of GH4945 superalloy was investigated by isothermal compression test in the temperature range of 1000--1200 ℃with strain rates of 0.001 10.000 s 1 toa total strain of 0.7. Dynamic recrystallization is the primary softening mechanism for GH4945 superalloy during hot deformation. The constitutive equation is established, and the calculated apparent activation energy is 458. 446 kJ/moh The processing maps at true strains of 0.2, 0.4 and 0.6 are generally similar, dem- onstrating that strain has little influence on processing map. The power dissipation efficiency and in- stability factors are remarkably influenced by deformation temperature and strain rate. The optimal hot working conditions are determined in temperature range of 1082 -1131 ℃ with strain rates of 0.004--0.018 s-1. Another domain of1134--1150 ℃ and 0. 018 0.213s ^- can also be selected as the optimal hot working conditions. The initial grains are replaced by dynamically reerystallized ones in optimal domains. The unsafe domains locate in the zone with strain rates above 0, 274 s^- 1, mainly characterized by uneven microstructure. Hot working is not recommended in the unsafe domains.

The performance of a lubricant largely depends on the additives it involves. However, currently used additives cause severe pollution if they are burned and exhausted. Therefore, it is necessary to develop a new generation of green additives. Graphene oxide（GO） consists of only C, H and O and thus is considered to be environmentally friendly. So the tribological properties of the few-layer GO sheet as an additive in hydrocarbon base oil are investigated systematically. It is found that, with the addition of GO sheets, both the coefficient of friction（COF） and wear are decreased and the working temperature range of the lubricant is expanded in the positive direction. Moreover, GO sheets has better performance under higher sliding speed and the optimized concentration of GO sheets is determined to be 0.5wt%. After rubbing, GO is detected on the wear scars through Raman spectroscopy. And it is believed that, during the rubbing, GO sheets adhere to the sliding surfaces, behaving like protective films and preventing the sliding surfaces from contacting with each other directly. This paper proves that the GO sheet is an effective lubricant additive, illuminates the lubrication mechanism, and provides some critical parameters for the practical application of GO sheets in lubrication.

Anisotropic MnBi/NdFeB （MnBi contents of 0 wt%, 20 wt%, 40 wt%, 60 wt%, 80 wt%, and 100 wt%） hybrid bonded magnets were prepared by molding compression using MnBi powders and commercial hydro-genation disproportionation desorption and recombination （HDDR） NdFeB powders. Magnetic measurements at room temperature show that with MnBi content increasing, the magnetic properties of the MnBi/NdFeB hybrid bonded magnets all decrease gradually, while the density of the hybrid magnets improves almost linearly. In a temperature range of 293-398 K, the coercivity temperature coefficient of the hybrid magnets improves gradually from -0.59 %.K^-1 for the pure NdFeB bonded magnet to -0.32 %.K^-1 for the hybrid bonded magnet with 80 wt% MnBi, and the pure MnBi bonded magnet exhibits a positive coercivity temperature coefficient of 0.61%-K^-1.

High-strength Cu-3Ag-0.5Zr alloy plates were produced by multi-pass rolling in the temperature range of 500-800 ℃. An increase in strength was observed by rolling in the aforementioned range without significant loss in ductility. All the rolled samples show higher strength than solution-treated and aged samples. The maximum strength was observed for plates rolled at 500 ℃ with a yield strength and ultimate tensile strength of 311 and 385 MPa, respectively, and retaining a ductility of 23 %. Transmission electron microscopy （TEM） studies showed uniform distribution of fine silver precipitates and high dislocation density in the rolled samples. Nevertheless, the size of precipitates and dislocation density varied with the rolling temperature. The superior strength achieved in the rolled samples is attributed to grain refinement, dislocation strengthening, and precipitation hardening. This method can be employed to produce high-strength plates of pre- cipitation hardenable copper alloys.