Hydrothermal systems have prevailed throughout geological history on earth, and ancient ARCHAEAN hydrothermal deposits could provide clues to understanding earth's earliest biosphere. Modern hydrothermal systems support a plethora of microorganisms and macroorganisms, and provide good comparisons for paleontological interpretation of ancient hydrothermal systems. However, all of the microfossil...

Tungsten oxide (WO3) nanostructure were synthesized by a facile hydrothermal method at 150° C using tungstate dehydrates (Na2WO4.2H2O) as the precursor. Without any additive, scanning electron microscopy revealed a rhombus shaped WO3 nanostructures while with the addition of sodium chloride, the morphology changes to nano-dagger bundles that formed flower-like structure. Furthermore, the size o...

We report here the successful fabrication of nano-whisker hydroxyapatite (nHA) coatings on Mg alloy by using a simple one-step hydrothermal process in aqueous solution. The nHA coating shows uniform structure and high crystallinity. Results indicate that nHA coating is promising for improving the in vitro corrosion and cytocompatibility properties of Mg-based implants and devices for bone tissu...

[1] Diffuse flow velocimetry (DFV) is introduced as a new, noninvasive, optical technique for measuring the velocity of diffuse hydrothermal flow. The technique uses images of a motionless, random medium (e.g., rocks) obtained through the lens of a moving refraction index anomaly (e.g., a hot upwelling). The method works in two stages. First, the changes in apparent background deformation are c...

In the past few decades, chemosynthetic ecosystems at deep-sea hydrothermal vents have received attention as plausible analogues to the early ecosystems of Earth, as well as to extraterrestrial ecosystems. These ecosystems are sustained by chemical energy obtained from inorganic redox substances (e.g., H2S, CO2, H2, CH4, and O2) in hydrothermal fluids and ambient seawater. The chemical and isot...

A hydrothermal method of synthesizing hydroxyapatite by heating a precipitate, formed by mixing Ca(NO3)2⋅4H2O and (NH4)2HPO4 with distilled water, in a hydrothermal reactor at 200 C for 24-72 hrs is described. A treatment time of 24 hrs produced single phase (as shown by XRD) hydroxyapatite powder, however for longer treatment times XRD patterns were indicative of the presence of a secondary ph...

The paper reports the preparation and photocatalytic activity of ZnO/SnO2 and SnO2 nanoparticles. These nanoparticles were synthesized by hydrothermal method. The products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Their grain sizes are about 50-100 nm. The photocatalytic activities of these materials were investigated for congo red removal from aqueou...

Single-crystalline SnO2 microcubes were grown using the hydrothermal method without any catalyst. X-ray diffraction (XRD) patterns and energy dispersive X-ray (EDX) analysis verified that the cubes are tin dioxide SnO2. Their morphology and structure was studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and Raman 5m...

Porous MnO/C nanotubes are synthesized by a facile hydrothermal method followed by thermal annealing, and possess excellent cyclability and high rate capability as an anode for lithium ion batteries.

Recently hierarchical architectures, consisting of two-dimensional (2D) nanostructures, are of great interest for potential applications in energy and environmental. Here, novel rose-like WO₃ hierarchical architectures were successfully synthesized via a facile hydrothermal method. The as-prepared WO₃ hierarchical architectures were in fact assembled by numerous nanosheets with an average thick...