Zinc oxide (ZnO) powders were synthesized by a simple hydrothermal process in the temperature range of 50 to 100 C. Nanocrystallites were formed by a simple hydrothermal route from aqueous solutions of zinc nitrate hexahydrate (Zn(NO3)2·6H2O) and NaOH under controlled process conditions such as precursor concentration (0.07 to 1 mol/L), reaction pH (7 to 11) and temperatures. Single phase ZnO p...

As seed dormancy is released within a seed population, both the rate and percentage of germination increase progressively with increasing dose of a dormancy-breaking treatment or condition. Population-based models can account for this behaviour on the basis of shifting response thresholds as dormancy is alleviated. In particular, hydrothermal time analysis of germination sensitivity to water po...

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...

Attapulgite (APT) has been frequently used for the adsorptive removal of dyes from aqueous solution owing to its unique one-dimensional nanoscale structure and low-cost, abundant, eco-friendly advantages. In this work, APT was functionalized under mild hydrothermal condition using chloroacetic acid (CA) with COOH functional groups to improve its adsorption properties. The effect of hydrothermal...

Photoluminescent graphene quantum dots (GQDs) have received enormous attention because of their unique chemical, electronic and optical properties. Here a series of GQDs were synthesized under hydrothermal processes in order to investigate the formation process and optical properties of N-doped GQDs. Citric acid (CA) was used as a carbon precursor and self-assembled into sheet structure in a ba...

introduction the shahrestanak mn deposit is located in southern qom province, 12 km southwest of the city of kahak. based on geological-structural divisions of iran, the deposit belongs to central volcanic belt or urumieh-dokhtar zone. the venarch deposit is one the most important known manganese deposits in iran. the sharestanak and venarch deposits are spatially and temporally related to each...

lithium disilicate nano-powders were synthesized via a mild condition hydrothermal reaction at 180 ºc for 48 and 72 h with a non stoichiometric1:2 li:si molar ratio in naoh aqueous solution using li2co3 and sio2.h2o as raw materials. the synthesized materials were characterized by powder x-ray diffraction (pxrd) technique and fourier transform infrared (ftir) spectroscopy. the xrd data showed t...

Lithium disilicate nano-powders were synthesized via a mild condition hydrothermal reaction at 180 ºC for 48 and 72 h with a non stoichiometric1:2 Li:Si molar ratio in NaOH aqueous solution using Li2CO3 and SiO2.H2O as raw materials. The synthesized materials were characterized by powder X-ray diffraction (PXRD) technique and Fourier transform infrared (FTIR) spectroscopy. The XRD data showed t...

nano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and solvents.  this nano-sized sulfated titania has been prepared by a sol-gel hydrothermal process. the prepared sulfated titania s...