We have performed a muon spin rotation study on polycrystalline samples of electron-doped layered manganites, La2-2xSr1+2xMn2O7 (0.4< or =x<1), in order to investigate the local magnetic structure and spin dynamics. Our results provide evidence for phase separation into A-type antiferromagnetic and charge-ordered phases for x=0.52 and spin freezing at low temperatures (T<100 K) for 0.52< or =x<...

introduction: to evaluate the quick cryopreservation technique on parameters of motility, morphology, and vitality of spermatozoa from normozoospermic ejaculates. materials and methods: in this prospective study, a total of 37 normal ejaculates were evaluated according to who criteria, then each sample was divided into two aliquets and sample was cryopreserved with quick freezing method. sperm ...

The product to be handled in a refrigerated facility defines the building's function. Will the incoming product be fresh or frozen? If the product is fresh, how much and what kind of further processing will there be done in the facility? This consideration will define the need for ice production and handling, special cutting, portioning, or other processing and/or cooking machinery. Will the fu...

Ultrasonic acoustic emission analysis enables nondestructive monitoring of damage in dehydrating or freezing plant xylem. We studied acoustic emissions (AE) in freezing stems during ice nucleation and propagation, by combining acoustic and infrared thermography techniques and controlling the ice nucleation point. Ultrasonic activity in freezing samples of Picea abies showed two distinct phases:...

abstract r. ficaria is an invasive perennial and tuberous roots weed. the most important means of its reproduction and dispersion are tubers. in order to study the effect of droughty and freezing on germination of lesser celandine tubers, two experiments were conducted at weed science laboratory of faculty of agriculture ferdowsi university of mashhad in 2008. the experiment was a completely ra...

The warm rain process refers to the precipitation formation from warm clouds, which involves no ice phase through the whole process. Therefore, the entire cloud is below the freezing height all the time, unless cloud droplets are supercooled, so they remain in the liquid phase below the freezing temperature. This process is commonly observed in, but not limited to, tropical regions because of h...

Using molecular simulations and free energy calculations based on Landau theory, we show that freezing/melting behavior of fluids of small molecules in pores of simple geometry can be understood in terms of two main parameters: the pore width H* ~expressed as a multiple of the diameter of the fluid molecule! and a parameter a that measures the ratio of the fluid-wall to the fluid–fluid attracti...

Freezing of polydisperse hard spheres is studied by Monte Carlo simulation and the results are interpreted with a cell model of the solid. The results supplement an earlier study of freezing of nearly monodisperse hard spheres and, within the assumption of a substitutionally disordered solid, a complete description of the freezing behavior is obtained. The density and polydispersity of the prec...

This paper describes a technique to determine the linear wellposedness of a general class of vector elliptic problems that include a steady interface, to be determined as part of the problem, that separates two subdomains. The interface satisfies mixed Dirichlet and Neumann conditions. We consider “2+2” models, meaning two independent variables respectively on each subdomain. The governing equa...