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Eigenschaften organischer Schmelzemulsionen, wie beispielsweise deren Haltbarkeit oder der Kristallisationsprozess der dispersen Phasen, werden stark von der Zusammensetzung der Emulsion beeinflusst. In der Literatur wird erörtert, dass die chemische Ähnlichkeit zwischen der hydrophoben Gruppe der Tenside und der dispergierten Phase die Kristallisation der Dispersphase auslösen kann. Die hier vorliegende Arbeit konzentriert sich auf die mögliche Auswirkung von Fremdkörpern, wie zum Beispiel von Wachsen, auf die Kristallisation von Tröpfchen, da sie als aktive Keimbildungscluster (active nucleation cluster, kurz: ANC) wirken und ebenfalls die Keimbildung auslösen können. Es wurde gezeigt, dass ANCs mit ähnlicher Polarität wie die dispergierte Phase den Kristallisationsprozess beschleunigen und zu einer Kristallisation bei geringerer Unterkühlung führen, was eine nachhaltigere Emulsionsproduktion ermöglichen könnte, da weniger Energie für die Kühlung benötigt wird. Außerdem wurde gezeigt, dass dieselben ANCs, die die Kristallisationsgeschwindigkeit erhöhten, die Lagerstabilität einer organischen Öl-in-Wasser-Emulsion verbessern. [ABSTRACT FROM AUTHOR]

The article presents a study on the nature of glass-ceramic nucleation by exploring the energy landscape of a barium disilicate system that captures the crystalline basins. Topics discussed include the phenomenological steps in the phase transformation of a supercooled liquid to a crystal, the challenges in optimizing glass-ceramic design, the difficulty in stimulating crystal nucleation, and variation in the results of classical nucleation theory.

The article offers information on propagation of ripplocations and layered crystalline solids deform via nucleation, and mentions behavior in layered materials.

The article discusses the significant innovations introduced by Milliken Chemical in the area of polypropylene (PP) nucleation and their benefits for injection molders of PP. Milliken's class of "Hyper" nucleating agents combine the highest crystallization rates and isotropic shrinkage with end-product physical properties. Polymer properties that can be affected by the addition of nucleating agents include stiffness and impact resistance. Ways to address pigment problems are also discussed.

The article discusses a study conducted at the Stanford's Linear Accelerator LAB (SLA) to discover the crystal growth of diamonds at an atomic level. Topics include nucleation growth of diamonds, growing synthetic diamonds using chemical vapor deposition (CVD), and using diamondoids from petroleum to synthesize nanocrystals of diamonds.

The article reports that Northwestern University scientists Austin M. Evans and colleagues have developed a two-step synthesis strategy to grow 2-D covalent organic frameworks (COFs), which include nucleation to form suspension of COF-5 nanoparticles and monomers to form 2-D colloidal crystals.

The article looks at a study by researcher Valeria Molinero and others which suggests that the nanoscopic ice seeds actually begin as a mix of hexagonal and cubic layers stacking disordered structure. It mentions classical nucleation theory assumes that the nucleus is like a piece of the bulk phase and ice seeds are entropically favored over the hexagonal form. It also mentions simulations show that stacking disordered ice nucleation predicted by classical nucleation theory.

The article presents a study published in the journal "Science" in 2014 in which James J. De Yoreo on crystal nucleation. The study carried out liquid-cell transmission electron microscopy imaging of calcium carbonate nucleation and the imaging revealed multiple crystallization pathways occurring in a single solution at the same time. The study also found that role of moelcular cluster in the formation of stable crystals are poorly understood.

The article focuses on a research conducted to track the nanoparticle growth with a "label," a metallic seed. By using labeling method, researchers have come to know that changes in shape of metallic nanoparticles, as they grow, could help them better control the materials' electronic and catalytic properties. They believe that the labeling technique could help study the nucleation and growth mechanisms of nanocrystals.

The article discusses a research study on the effects of cosmic rays on the nucleation of sulfuric acid (H2SO4) which appeared in a 2011 issue of the journal "Nature."

The article focuses on a study by researchers at Purdue University that developed a sensitive way to probe nucleation and growth kinetics at the earliest stages of crystal formation.

The article reports on the low intensity laser technique that can be utilize for crystallization. Based on the observation conducted by the Polytechnic Institute of New York University, it shows that the technique can obtain a supersaturated urea that leads to crystallization in a process called nonphotochemical laser- induced nucleation (NPLIN). However, it mentions that there are things still needed to be resolved in utilizing the NPLIN.

The article reports on a study conducted by Lidia Morawska of Queensland University of Technology in Brisbane, Australia which demonstrated that particles are not generated directly from laser printers. The particles formed in the air from volatile organic compounds originating from the paper and hot toner. The particles were formed either by spontaneous homogeneous nucleation or secondary particle formation involving ozone.

The article reports that researcher Ruikang Tang and colleagues at Zhejiang University have devised a way to protect yeast cells with a mineral coating that can extend the shelf life of cells during storage. The researchers changed the surface properties of the yeast cell with a mixture of polyelectrolytes. The polyelectrolytes provide active nucleation sites for the precipitation of calcium phosphate on the cell, which becomes completely encased in the mineral.

The article discusses research being done on homogeneous nucleation, a theory describing the molecular mechanism that causes bubbles to form in a liquid. It references a study led by Davis Corti, published in the August 2007 issue of "Physical Review Letters."The study's findings contradict the theory, claiming that bubble grows via a mechanism different from the classical nucleation concept.

The article reports on the recent development of a PP transparent nucleating agent DMDBS pilot technology by PetroChina Jilin Petrochemical Co. DMDBS is recognized as a nucleating agent for plastic products.

The article reports that scientists in Netherlands have uncovered some of the key steps in molecular nucleation and growth mechanism. The study examines the dependence of various states of molecular aggregation on temperature and reveals a crucial role played by solvent molecules in the assembly process. The research team includes Pascal Jonkheijim, E. W. Meijer and Albertus P. H. J. Schenning. The key finding of the study is discussed.

Presents news items on discoveries in biochemistry in the U.S. as of May 19, 2003. Study on nucleation in polymorphic systems; Popularity of biphasic solvent systems for homogeneous catalysis; Use of a potent inhibitor of cholesterol ester transfer protein for atherosclerosis.

Reports on the efficacy of polarized laser radiation in controlling crystallization in the U.S. Nucleation of urea in a few nanoseconds; Alignment of the needle-shaped crystals to the electric field direction of the laser light; Mechanics of crystal nucleation.