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A new borogermanate, viz. piperazine-1,4-diium difluorononaoxotrigermaniumdiboron, (C(4)H(12)N(2))[(GeO(2))(3)(BO(1.5)F)(2)], was solvo/hydrothermally synthesized. The crystal structure consists of layers composed of three-membered-ring Ge(3)O(9) subunits and nine-membered-ring channels formed by six GeO(4) tetrahedra and three BO(3)F tetrahedral pairs. The diprotonated piperazine cations, which lie about inversion centres, are located between adjacent layers and connect the layers via hydrogen bonds.

Zeolites have been extensively studied over many years due to their widely applications in catalysis, ion exchange, adsorption, and separation.[1] Knowing the structure of zeolite is important for understanding their properties and predicting possible applications of such materials. Structure determination of zeolites has remains challenging, as submicro-and nano-sized crystals are often obtained. Here, we elucidate a novel germanate-based zeolite PKU-14 with a 3D 12*12*12-ring channel system. The structure was solved by combing high-resolution PXRD, rotation electron diffraction method, NMR and IR spectroscopy. Ordered Ge4O4 vacancies inside the [46612] cages has been found in PKU-14, where a unique water dimer was located at the vacancies and played a structure-directing role.

Intense earthquake shaking inevitably ruptures the rockmass along the fissures and bursts mountainous slopes, and these understable slopes are namely cracked slopes. For such slopes, aftershocks, rainwater infiltration and others factors will inevitably induce crack propagation and the crack thus gradually accumulates to be the cutting boundary that controls the slope deformation and failure. To understand how the slope stability varies in the process of cracking expanding, upper bound approach is employed to assess the cracked slope in Wenchuan earthquake epicenter considering the effects of crack propagation, rainwater infiltrating and earthquake. The results conducted in this paper indicate that the crack propagation lowly reduces the slope stability and it does not directly destabilize the slope. But the crack length owing to propagation inevitably increases the probability of slope failure, which more depend on the filling water in the crack and the earthquake intensity.

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