Liquid water can persist in a supercooled state to below 238 K in the Earth's atmosphere, a temperature range where homogeneous nucleation becomes increasingly probable. However, the rate of homogeneous ice nucleation in supercooled water is poorly constrained, in part, because supercooled water eludes experimental scrutiny in the region of the homogeneous nucleation regime where it can exist o...

Streptomycin (100 micrograms per milliliter), desiccation (over CaSO(4)), and ultraviolet radiation (4500 microwatts per square centimeter at 254 nanometers for 15 minutes) reduced ice nucleation activity by Pseudomonas viridiflava strain W-1 as determined by freezing drops of the bacterial suspensions. Highest residual ice nucleation activity by dead cells was obtained by desiccation, although...

The environmental chamber of a molecular beam apparatus is used to study deposition nucleation of ice on graphite, alcohols and acetic and nitric acids at temperatures between 155 and 200 K. The critical supersaturations necessary to spontaneously nucleate water ice on six different substrate materials are observed to occur at higher supersaturations than are theoretically predicted. This contr...

Background; Pollution of drinking water and ice is one of the most serious ways of water borne diseases spread. The purpose of this study was to investigate the bacterial contamination of the ice produced by ice factories in Bandar Abbas. Methods; In this descriptive ,cross-sectional study samples were collected from seven ice factories in Bandar Abbas. Sampling was done by standard method.   ...

The mechanism of ice nucleation to form Type 2 PSCs is important for controlling the ice particle size and hence the possible dehydration in the polar winter stratosphere. This paper probes heterogeneous ice nucleation on sulfuric acid tetrahydrate (SAT). Laboratory experiments were performed using a thin-film, high-vacuum apparatus in which the condensed phase is monitored via Fourier transfor...

The recently developed Zurich Ice Nucleation Chamber (ZINC) was used to explore ice nucleation of size-selected mineral dust particles at temperatures between −20C and −55C. Four different mineral dust species have been tested: montmorillonite, kaolinite, illite and Arizona test dust (ATD). The selected particle diameters are 100 nm, 200 nm, 400 nm and 800 nm. Relative humidities with respect t...

Coarse grained molecular dynamics simulations are presented in which the sensitivity of the ice nucleation rate to the hydrophilicity of a graphene nanoflake is investigated. We find that an optimal interaction strength for promoting ice nucleation exists, which coincides with that found previously for a face centered cubic (111) surface. We further investigate the role that the layering of int...

A parametrization of cirrus clouds formed by homogeneous nucleation is improved so that it can be used more easily in general-circulation models (GCMs) and climate models. The improved parametrization is completely analytical and requires no fitting of parameters to models or measurements; it compares well with full microphysical model results even when monodisperse aerosol particles are used i...

Application of power ultrasound to Food freezing is a relatively new subject, cavitations is the most significant power which can not only lead to the production of gas bubbles in ice ream but also the occurrence of micro streaming, also it can promote ice nucleation to accelerate the heat and mass transfer process accompanying the freeze process. In this work ice cream freezing process time af...