Estimating the NH3:H2SO4ratio of nucleating clusters in atmospheric conditions using quantum chemical methods T. Kurtén, L. Torpo, M. R. Sundberg, V.-M. Kerminen, H. Vehkamäki, and M. Kulmala Division of Atmospheric Sciences, Department of Physical Sciences, P.O.Box 64, FI-00014 University of Helsinki, Finland Laboratory of Inorganic Chemistry, Department of Chemistry, P.O. Box 55, FI-00014 Uni...

Publications of recent years dealing with laboratory experiments of immersion freezing reveal uncertainties about the fundamentals of heterogeneous freezing nucleation. While it appears well accepted that there are two major factors that determine the process, namely fluctuations in the size and configuration of incipient embryos of the solid phase and the role of the substrate to aid embryo fo...

The nucleating activity of the Arp2/3 complex promotes the assembly of branched actin filaments that drive plasma membrane protrusion in migrating cells. Arp2/3 complex binding to nucleation-promoting factors of the WASP and WAVE families was previously thought to be sufficient to increase nucleating activity. However, phosphorylation of the Arp2 subunit was recently shown to be necessary for A...

BACKGROUND Nucleation of cholesterol monohydrate crystals following the aggregation and fusion of cholesterol-enriched vesicles is a critical procedure in the formation of cholesterol gallstone. Biliary proteins play important roles in the process. It is inefficient to screen pro-nucleating or anti-nucleating proteins with routine physiochemical techniques, by which we discovered several pro-nu...

Homogeneous dispersion of graphene into thermoplastic polymer matrices during melt-mixing is still challenging due to its agglomeration and weak interfacial interactions with the selected matrix. In this study, an ideal within PA66 matrix was achieved under high shear rates by thermokinetic mixing. The flow direction monitored developed numerical methodology a combination rheological behaviors....

Abstract Biocomposites of poly(lactic acid) (PLA) and pectin, which are low-cost organic materials, were prepared using an internal mixing machine in various pectin contents, i.e., 2, 4, 6 8% w/w. When was added as a nucleating agent, the mechanical properties biocomposites, such tensile impact testing, considerably improved, particularly following annealing process. In addition, PLA–pectin ann...

In most eukaryotic cells, microtubules (MTs) are assembled at identified nucleating sites, such as centrosomes or spindle pole bodies. Higher plant cells do not possess such centrosome-like structures. Thus, the fundamental issues of where and how the intracellular plant MTs are nucleated remain highly debatable. A large body of evidence indicates that plant MTs emerge from the nuclear peripher...

Heterogeneous ice nucleation is an important process in many fields, particularly atmospheric science, but is still poorly understood. All known inorganic ice nucleating particles are relatively large in size and tend to be hydrophilic. Hence it is not obvious that carbon nanomaterials should nucleate ice. However, in this paper we show that four different readily water-dispersible carbon nanom...

Magnetic nanoparticles based on Fe3O4 were prepared by a facile and rapid one-pot solvothermal synthesis using FeCl3·6H2O as a source of iron ions, ethylene glycol as a solvent and NH4Ac, (NH4)2CO3, NH4HCO3 or aqueous NH3 as precipitating and nucleating agents. In contrast to previous reports we reduce the synthesis time to 30 minutes using a pressurized microwave reactor without the requiremen...

Polylactic acid (PLA), a potential alternative material for single use plastics, generally portrays slow crystallization rate during melt-processing. The of nanomaterial such as cellulose nanofibers (CNF) may affect the by acting nucleating agent. CNF at certain wt.% has been evidenced good reinforcement PLA; nevertheless, there is lack information on correlation between amount in PLA that prom...