Janus materials with anisotropy shapes and chemical compositions, including Janus particles, Janus nanosheets, and Janus membranes, have a great significance in the development of new functional materials and expansion of the properties and applications of materials. This review summarizes recent works on Janus materials of preparation, application, assembly, and calculation. First, we briefly sort out the methods of preparing Janus particles and discuss the factors influencing the structure, shape, and size of Janus particles, pointing out their advantages and the direction of improvement. Then, we introduce in detail the applications field from a single Janus particle, assembly of Janus particles, 2D Janus nanosheet, and Janus membrane. We summarize the recent research on the self-assembly of Janus particles and point out the role of the combination of computational simulation and experiment in the research of Janus material. Finally, the research process of Janus materials is reviewed, and the development tendencies of Janus materials and the problems to be solved are summarized.

This paper examines the interaction between the spatial variations in binder concentration (i.e. cement slurry concentration) and in situ water content, in cement-mixed soil, using field and model data as well as statistical analysis and random field simulation. The field data are first analysed to shed light on the spatial variation in the in situ water content, including its scale of fluctuation. A statistical model is then developed which takes into account the variation in binder concentration and in situ water content. This leads to a two-parameter model for the prediction of the mean, variance and probability distribution function of the strength of the cement-treated soil. The scale of fluctuation for the variation in binder concentration arising from imperfect mixing within a cement-mixed column is then examined using centrifuge model data. This indicates that the scale of fluctuation in binder concentration is much shorter in range than that of the in situ water content. The combined effect of these two scales of fluctuation is then studied by simulating the resulting random field using Monte-Carlo simulations. This indicates that the size of the sampling region has a significant effect on the scale of fluctuation that is captured. If the sampling region is of a similar size to the column diameter, the measured scale of fluctuation reflects that of the binder concentration. As the size of the sampling region increases, so does the measured scale of fluctuation. This explains the wide range of scales of fluctuation that have been reported for cementtreated soil. To capture both scales of fluctuation in core sampling, some boreholes should be sunk at close spacings of less than a column diameter, in order to capture short-range variation.

Crosslinking significantly improves the toughness and impact strength of HDPE and extends its application, especially at low temperature.

The effect of geometric imperfections in both diameter and position of jet-grouted columns on the watertightness of an underground cement-treated slab is investigated in this study. A three-dimensional discretized algorithm is proposed to facilitate the detection and measurement of untreated zones that penetrate the treated slab. The normalized flow rate of a cement-treated slab is then evaluated by calculating the harmonic average area of the penetrated defect. Statistical evaluation of the gross flow rate through the penetrated defects is carried out via Monte Carlo simulations. The results show that a more economic design is obtainable if intracolumn variation of diameter is considered or multi-shaft jet-grouting is used. Based on the statistical results, a reliability-based design method is proposed for designers to strike a balance among various design parameters, including slab thickness, depth, column diameter, and column spacing.

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