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Rapid and deliberate patterning of nanomaterials over a large area is desirable for device manufacturing. We report a method for meniscus‐assisted self‐assembly (MASA)‐enabled rapid positioning of hierarchically assembled dots and stripes composed of luminescent conjugated polymer over two length scales. Periodically arranged conjugated poly(9,9‐dioctylfluorene) (PFO) polymers, yield dots, punch‐holes and stripes at microscopic scale via MASA. Concurrent self‐assembly of PFOs into two‐dimensional lenticular crystals within each dot, punch‐hole and stripe is realized at nanoscopic scale. Hierarchical assembly is achieved by constraining the evaporation of the PFOs solution in two approximately parallel plates via a MASA process. The three‐phase contact line (TCL) of the liquid meniscus of the PFOs was printed using the upper plate, yielding an array of curved stripes. Rapid creation of hierarchical assemblies via MASA opens up possibilities for large‐scale organization of a wide range of soft matters and nanomaterials. [ABSTRACT FROM AUTHOR]

Samples of Ni51Ti49 alloy subjected to plastic deformation have been studied. The microstructure was studied by transmission electron microscopy and microdifraction on a Hitachi 7700 microscope. The phase composition of the samples was determined by X-ray diffraction in a Bruker diffractometer. Magnetometric measurements were performed in an induction petlescope. Lenticular crystals (of the Ni2Ti3 phase containing bend–extinction contours indicating a significant curvature of the crystal lattice appearing in the localization zones of plastic deformation) were found in the deformation localization zones. It was revealed that the samples are non-magnetic before deformation, but after plastic deformation, they have non-zero magnetization, which is associated with the emergence of new phases. Under conditions of local curvature of the crystal lattice, special structural states arise in zones of increased interatomic distances, which increase the number of degrees of freedom in the deformable solid and thus contribute to the redistribution of the components of the initial solid solution and the appearance of new phases. It was shown that the crystalline structure of lenticular crystals is a phase constructed of a spinel structural type with a crystal lattice parameter of 11.53 ± 0.03 Å.

Gypsum soils are both a problem and a puzzle, which is precisely why they deserve attention. Gypseous (high-gypsum) soils generally occupy sparsely populated land with minimal land use intensity in arid and semiarid climates. Gypsum content in agricultural soils results in restricted water and nutrient retention and the potential for dissolution piping, primarily in response to irrigation. The corrosive effects of gypsum soils on concrete, metal, and building materials are also problematic. On the other hand, understanding the genesis and function of gypsiferous (low-gypsum) and gypseous soils is interesting and challenging, and our grasp of processes involved in the formation and behavior of these soils is critical for proper management for agricultural, rangeland, engineering, and construction purposes. The objective of this review was to examine the physical and chemical properties of gypsum and the impacts of these properties in the soil environment. The particular properties that gypsum presence imparts to soils affect soil development, including soil morphology. Accumulations of pedogenic gypsum influence water-holding capacity, nutrient and water availability for plants, root growth, and the standard concepts of soil texture and rupture resistance. Gypsum precipitation is also affected by the presence of more soluble salts. The development of physicochemical models that explain the formation and function of gypsiferous and gypseous soils is necessary if we hope to properly manage and maintain these unusual soils and their landscapes. [ABSTRACT FROM AUTHOR]