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A three‐dimensional (3‐D) resistivity model around the 2014 Ms6.5 Ludian earthquake was obtained. The model shows that the aftershocks were mainly distributed in a shallow inverse L‐shaped conductive angular region surrounded by resistive structures. The presences of this shallow conductive zone may be the key factor leading to the severe damage and surface rupture of the Ludian earthquake. A northwest trending local resistive belt along the Baogunao‐Xiaohe fault interrupts the northeast trending conductive zone at the Zhaotong‐Lianfeng fault zone in the middle crust, which may be the seismogenic structure of the main shock. Based on the 3‐D electrical model, combining with GPS, thermal structure, and seismic survey results, a geodynamic model is proposed to interpret the seismotectonics, deep seismogenic background, and deformation characterized by a sinistral strike slip with a tensile component of the Ludian earthquake.

In this work, we present a systematic study on the complete control over the sphere diameters of MCM-41 nanospheres with different pore sizes. The mesoporous silica nanospheres with diameter range from 40 nm to 160 nm are synthesized by using cationic quaternary ammonium surfactants as template and TEOS as silicon source in sodium hydroxide aqueous solution via sol-gel supermolecular method. Nanospheres with fixed diameter can be obtained through the precise control over the molar ratio of NaOH/TEOS and other synthetic conditions. The range of sphere diameter for each sample prepared under adjustable reaction conditions is in a sharp distribution. Moreover, the formation mechanism for nanospheres with controlled morphological and structural features is proposed, and we suggest the optimal synthesis conditions of the MCM-41 nanospheres for the minimization of the Gibbs free energy deltaG. Besides, after depositing vanadium species on the MCM-41 support, the catalytic performance of V-MCM-41 for the selective oxidation of styrene by hydroperoxide increases with the diameter of the supports decreasing.

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The Borneo Accretionary Orogen (BAO) is located in a central position of SE Asia, surrounded by the long‐lived westward subduction of the Pacific Plate, northward subduction of the Indian Plate beneath the Eurasian Plate and a passive continental margin of the South China Sea. Based on the previous studies in stratigraphy, structural geology and geophysics, a number of tectonic models on the BAO have been proposed, but these models do not perfectly match all of the geological facts. A field‐based structural analysis of the rocks of Sabah in Malaysia has recognized that the deformation in Sabah can be divided into four episodes (D1‐D4). The D1 deformation developed complete displacement foliation (S1) and NNE‐trending thrusts. Then D1 structures were reworked by the subsequent D2 deformation. D2 deformation resulted in WNW‐ or NW‐striking thrusts, followed by NNW–SSE‐trending thrusts and folds (D3). Some NNE‐trending sinistral strike‐slip faults and WNW‐trending dextral tension‐shear faults (D4) offset the D3 structures. D1 is related to the collisional event in the Sabah Orogeny during 23‐16 Ma, and D2 corresponds to the formation of the Deep Regional Uncomformity (DRU) at 16 Ma. D3 is related to the Shallow Regional Uncomformity (SRU) at 10 Ma. D4 is associated to the NW–SE‐trending extension after the multi‐stage collisional events. Analysis of the sedimentary and magmatic data reveals that the BAO is a Mesozoic and Cenozoic accretionary orogeny, represented by the intensely deformed Rajang‐Crocker Group Accretionary prism, ophiolites and calc‐alkaline igneous rocks. The accretionary orogen is related to the evolution of the Proto‐South China Sea Ocean (PSCS). The PSCS continuously subducted under the Borneo Block and closed in the Late Eocene–Early Miocene time. The subduction zone of the PSCS retreated to the north in the Mesozoic and Cenozoic and migrated to the present‐day Nansha Trough. The BAO is still active, as represented by a series of thrusting and subduction of the Dangerous Grounds under the Borneo Block. The NNE‐trending subduction‐related faults are considered as transform faults, rotating to the present‐day NW‐trending faults due to the anti‐clockwise rotation of the entire Borneo Block. In particular, the previous NNE‐trending Tinjar Fault is regarded as a major boundary in sedimentation and magmatism. To the NE of the fault, the strata and igneous rocks are Oligocene–Early Miocene, but to the SW of the fault, the strata and igneous rocks developed during the Cretaceous–Late Eocene interval. Copyright © 2016 John Wiley & Sons, Ltd.