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Microstructural analysis of MgO-MgAl 2 O 4 refractoryrefractory-liquid interface. 6-10 Furthermore, selective corrosion bricks corroded at 1400-1450؇C by calcium aluminosilicate may occur in which only certain phases in the solid are slag reveals secondary spinel, monticellite, merwinite, and attacked. The solubility of the solid in the liquid may be availMgO as microscopic corrosion products, generally forming able from the phase diagram, but often this is not known. in this sequence as the brick is penetrated. The secondaryNo single model can explain all cases of corrosion nor can it spinel forms an incomplete layer close to (but not at) the explain all corrosion mechanisms of a particular refractory in MgO grain. Thermodynamic calculations are used to supdifferent environments. The large variation in microstructure port a detailed model of the corrosion mechanism.for different ceramic types of essentially the same composition means that attack of a given composition in a particular environment may be affected by the microstructure. 11 Consequently, I. Introductionit is important to characterize the microstructure of the original A TTACK of refractories in commercial furnace linings is a refractory thoroughly prior to any corrosion test. It is known, complex phenomenon which, depending on the particular for example, that denser refractories corrode less since penetrasystem, involves many chemical wear (corrosion) and physical tion is hindered. The presence of a low melting and/or soluble or mechanical wear (erosion) processes which may interact boundary phase in the refractory grain leads to an increased synergistically. Chemical wear occurs as the system attempts to corrosion rate so that use of fused or tabular grains is beneficial come to equilibrium when the corrosive liquid (slag, metal, or in reducing corrosive wear. 12 For the same reasons large grain flux) is not saturated with a refractory component which it can sizes are used in refractory aggregates requiring corrosion resisdissolve. Thermodynamic equilibrium may only be achieved bytance. High open porosity in the refractory bond/matrix phase the liquid dissolving enough of that refractory component to is also deleterious, whereas rough (rugose) grains are physically become saturated. Corrosion of ceramics and refractories by held in the refractory, protecting against erosion. liquid silicates is poorly understood and proposed mechanisms However, to improve upon this rudimentary knowledge of are usually based on examination of simple systems such as the effect of microstructure on refractory corrosion requires that single crystals (e.g., Refs. 1 and 2).an understanding of the corrosion of the individual phases, i.e., On corrosion of a solid by liquid, reaction products (which of single crystals and of the types of bond phase (usually glass can be solid, liquid, gas, or a combination) may form which or carbon), be available. Only then can the influence of micro-(a) remain attached to the solid (usually solid or viscous liquid), structural texture (t...

The behavior of slag penetration into MgO refractory was investigated by combining in‐situ X‐ray observation with microstructural analysis of the samples after penetration experiments. The following results are obtained. The slag penetrates rapidly into the refractory, reacting with MgO particles in the refractory. The slag penetrates unevenly into the refractory with uneven pore size in a route like a tree, firstly along the main route (the surface of large MgO particles), and then extending to the branch route, while evenly into the refractory with even pore size. The rate of slag penetration increases with increasing pore radius and apparent porosity of the refractory, T · Fe concentration in the slag and temperature, and with decreasing the slag basicity (C/S ratio). In the case of the Al2O3‐bearing slag, the rate of slag penetration is less than that of Al2O3‐free slag in the initial stage. The penetration also stops much earlier than that of the Al2O3‐free slag, and then the penetration height remains almost constant. In the initial stage of penetration, the penetration height is proportional to the square root of penetration time. Slag penetration is deduced as stopping due to the following: (1) the melting point and viscosity of the penetrated slag increase, and the surface tension of the penetrated slag decreases with decreasing the FetO concentration in the penetrated slag consumed by the reaction between FetO and MgO particles; (2) in the 10mass% Al2O3‐bearing slag, the pore size in the refractory is reduced by the spinel formed on the pore surface by the reaction between Al2O3 in the penetrated slag and MgO particles in the refractory.

The purpose of the present study was to relate 3D acceleration patterns of the lower and upper trunk during running to running gait cycle, assess the validity of stride duration estimated from acceleration patterns, investigate speed-dependent changes in acceleration, and examine the test-retest reliability of these parameters. Thirteen healthy young men performed two running trials each on a treadmill and on land at three speeds (slow, preferred, and fast). The 3D accelerations were measured at the L3 spinous process (lower trunk) and the ensiform process (upper trunk) and synchronised with digital video data. The amplitude and root mean square of acceleration and stride duration were calculated and then analysed by three-way analysis of variance to test effects of running conditions, device location, and running speed. Bland-Altman analysis was used to evaluate the test-retest reliability. Marked changes in acceleration were observed in relation to foot strike during running. Stride durations calculated from the vertical accelerations were nearly equal to those estimated from video data. There were significant speed effects on all parameters, and the low test-retest reliability was confirmed in the anterior-posterior acceleration during treadmill running and the anterior-posterior acceleration at slow speed during treadmill and overground running.

Cellular mechanical properties are potential cancer biomarkers used for objective cytology to replace the current subjective method relying on cytomorphology. However, heterogeneity among intra/intercellular mechanics and the interplay between cytoskeletal prestress and elastic modulus obscured the difference detectable between malignant and benign cells. In this work, we collected high density nanoscale prestress and elastic modulus data from a single cell by AFM indentation to generate a cellular mechanome. Such high dimensional mechanome data was used to train a malignancy classifier through machine learning. The classifier was tested on 340 single cells of various origins, malignancy, and degrees of similarity in morphology and elastic modulus. The classifier showed instrument-independent robustness and classification accuracy of 89% with an AUC-ROC value of 93%. A signal-to-noise ratio 8 times that of the human-cytologist-based morphological method was also demonstrated, in differentiating precancerous hyperplasia cells from normal cells derived from the same lung cancer patient.