Two enantiomeric Zn-MOFs, having l- or d-proline chiral functionality, were achieved through in situ click reactions by modifying two opposite chiral adducts within the same pre-assembled achiral MOFs, respectively. Both of them exhibited remarkable catalytic activities in the relative asymmetric aldol reactions, and led to the formation of opposite enantiomorphs. The significant advantage of this approach not only includes the conversion of chemically and thermally robust MOFs into enantiomeric chiral material having catalytically active sites, but also involves the potential applications in asymmetric transformations with desirable chiralities of a special enantiomorph.

A novel metamaterial filter with stable passband performance based on frequency selective surface AIP Advances 4, 077114 (2014); 10.1063/1.4890108Self-biased planar millimeter wave notch filters based on magnetostatic wave excitation in barium hexagonal ferrite thin films Appl. Phys. Lett. 97, 173502 (2010); 10.1063/1.3504256Determination of magnetic properties of ultrathin iron films using microwave stripline technique

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The Interferometric Synthetic Aperture Radar (InSAR) technique is a well-developed remote sensing tool which has been widely used in the investigation of landslides. Average deformation rates are calculated by weighted averaging (stacking) of the interferograms to detect small-scale loess landslides. Heifangtai loess terrace, Gansu province China, is taken as a test area. Aiming to generate multi-temporal landslide inventory maps and to analyze the landslide evolution features from December 2006 to November 2017, a large number of Synthetic Aperture Radar (SAR) datasets acquired by L-band ascending ALOS/PALSAR, L-band ascending and descending ALOS/PALSAR-2, X-band ascending and descending TerraSAR-X and C-band descending Sentinel-1A/B images covering different evolution stages of Heifangtai terrace are fully exploited. Firstly, the surface deformation of Heifangtai terrace is calculated for independent SAR data using the InSAR technique. Subsequently, InSAR-derived deformation maps, SAR intensity images and a DEM gradient map are jointly used to detect potential loess landslides by setting the appropriate thresholds. More than 40 active loess landslides are identified and mapped. The accuracy of the landslide identification results is verified by comparison with published literatures, the results of geological field surveys and remote sensing images. Furthermore, the spatiotemporal evolution characteristics of the landslides during the last 11 years are revealed for the first time. Finally, strengths and limitations of different wavelength SAR data, and the effects of track direction, geometric distortions of SAR images and the differences in local incidence angle between two adjacent satellite tracks in terms of small-scale loess landslides identification, are analyzed and summarized, and some suggestions are given to guide the future identification of small-scale loess landslides with the InSAR technique.

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Abstract. On 5 June 2009, a catastrophic rockslide debris flow occurred at the crest of the Jiweishan range, Chongqing Municipality, China, killing 74 people and injuring an additional eight. We use L-band ALOS/PALSAR imagery to address landslide processes before, during and after the slide. We employ three different SAR methods, i.e., short baseline subsets (SBAS) interferometric SAR (InSAR), SAR backscattering intensity change, and InSAR stacking algorithm, to study any ground deformation before the rockslide, investigate the affected area, and calculate the topographic change by this slide, respectively. First, continuous deformation has been observed based on the available ALOS/PALSAR InSAR imagery during June and December 2007. Second, the area affected by the landslide can be inferred based on changes in SAR backscattering intensity as well as surface topography, with an estimated area of 0.47 million m2. Last, an InSAR-derived post-slide digital elevation model has allowed us to estimate surface height changes due to the slide, reaching about −80 m at the source region and about 60 m in the deposit region, respectively. Our InSAR-derived estimates have been validated using in situ data and 3-D lidar measurements.