A robust hydrogen-bonded organic framework HOF-TCBP (H TCBP=3,3',5,5'-tetrakis-(4-carboxyphenyl)-1,1'-biphenyl) has been successfully constructed and structurally characterized. It possesses a permanent 3D porous structure with a 5-fold interpenetrated dia topological network. This activated HOF-TCBP has a high BET surface area of 2066 m g and is capable of highly selective adsorption and separation of light hydrocarbons under ambient conditions. It shows excellent thermal stability, as demonstrated by PXRD experiments and N adsorption tests. Practical use of HOF-TCBP is facilitated by the ease of its preparation and renewal through rotary evaporation.

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Adsorption‐based separation is an important technology for C2H2 purification due to the environmentally friendly and energy‐efficient advantage. In addition to the high selectivity of C2H2/CO2, the high uptake of C2H2 also plays an important role in the separation progress. However, the trade‐off between adsorption capacity and separation performance is still in a dilemma. Herein, we report a series of cage‐like porous materials named FJI‐H8‐R (R=Me, Et, nPr and iPr) which all have high C2H2 uptakes at 1 bar and 298 K. Dynamic breakthrough studies show that they all exhibit excellent C2H2/CO2 separation performance. Particularly, FJI‐H8‐Me possesses a long breakthrough time up to 90 min g−1. Additionally, Grand Canonical Monte Carlo (GCMC) simulation reveals that the suitable pore space and geometry contribute much to the excellent separation performance.

Using hydraulic parameters is essential for describing soil detachment and developing physically based erosion prediction models. Many hydraulic parameters have been used, but the one that performs the best for describing soil detachment on steep slopes when the lateral expansion (widening) of rills is not limited has not been identified. An indoor concentrated flow scouring experiment was performed on steep loessial slopes to investigate soil detachment rates for different flow rates and slope gradients. The experiments were conducted on a slope‐adjustable plot (5 m length, 1 m width, 0.5 m depth). Sixteen combinations of 4 flow rates (10, 15, 20, and 25 L/min) and 4 slope gradients (17.6%, 26.8%, 36.4%, and 46.6%) were investigated. The individual and combined effects of slope gradient and flow hydraulic parameters on soil detachment rate were analysed. The results indicated that soil detachment rate increased with flow rate and slope gradient. Soil detachment rate varied linearly and exponentially with flow rate and slope gradient, respectively. Multivariate, nonlinear regression analysis indicated that flow depth exerted the greatest influence on the soil detachment rate, followed by unit discharge per unit width, slope gradient, and flow rate in this study. Shear stress and stream power could efficiently describe the soil detachment rate using a power equation. However, the unit stream power and unit energy of the water‐carrying section changed linearly with soil detachment rate. Stream power was an optimal hydraulic parameter for describing soil detachment. These findings improve our understanding of concentrated flow erosion on steep loessial slopes.

The syntheses and structures of two new Zn(II) complexes, a 2D graphite-like layer {[Zn(PIA)H2 O]⋅H2 O}n (1) and an independent 1D single-walled metal-organic nanotube (SWMONT) {[Zn2 (PIA)2 (bpy)2 ]⋅2.5 H2 O⋅DMA}n (2), have been reported based on a "Y"-shaped 5-(pyridine-4-yl)isophthalic acid ligand (H2 PIA). Interestingly, the 2D graphite-like layer in 1 can transform into the independent 1D SWMONT in 2 with addition of 2,2'-bipyridine (bpy), which represents the first successfully experimental example of an independent 1D metal-organic nanotube generated from a 2D layer by a "rolling-up" mechanism.

We herein present a rarely seen (3,4)-connected non-interpenetrated anionic uranium-organic framework with tbo topology (FJI–H-U1), which is constructed from two kinds of ultralarge nanocages. More importantly, FJI–H-U1 can selectively adsorb positively charged organic dyes Ethyl Violet, Janus Green B, and Rhodamine B over the anionic organic dye Methyl Orange due to the nature of its anionic framework.

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The stability of soil aggregates is closely connected with particle interaction determined by the combination of the van der Waals attractive force and electric repulsive force according to Derjaguin-Landau-Verwey-Overbeek (DVLO) theory. Recently, hydration force and dispersion force were put forward to explain the different behaviours of cations or anions of the same valence at the ion-surface interface, namely the specific ion effect, where the application of classical DLVO theory had failed. Here, we employed two cation species, potassium and sodium (K + and Na + ), to discover how the specific ion effect would influence clay aggregate stability. The stability of K + -and Na + -montmorillonite aggregates was determined under different electrolyte concentrations, indicated by the mass percentages of particles with diameters of < 10, < 5 and < 2 μm released after aggregate breakdown. There were large differences in the stability of the K + -and Na + -aggregates, and strong specific ion effects were shown. These effects could not be explained by the differences in ionic size, hydration and ion-surface dispersion forces between K + and Na + . We have proved that the difference in polarization between the K + and Na + at the charged clay surface was responsible for the specific ion effects. The difference in polarization observed between the adsorbed K + and Na + was hundreds to thousands of times larger than classical values; these results were also verified independently with different methods. The strong non-classical polarization of the adsorbed cation decreased the electric field and the electrostatic repulsion between adjacent particles in the aggregates, and thus strongly increased the aggregate stability.