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Out-plane weak ferromagnetic (OWFM) spin arrangements with topological properties can realize a series of interesting physical properties. However, this spin structure tends to exist at low temperatures. The OWFM structure can also be induced at room temperature by hydrostatic pressure, but this isotropic approach tends to form helical AFM structures. We report the OWFM spin arrangement in single crystal Mn3Sn by an anisotropic strategy of high-stress-constrained compression deformation at room temperature. Both experiments and theoretical simulations show that the alignment of OWFM spin structure is due to the distortion of the atomic scale caused by the strain energy during deformation. The OWFM spin arrangement can significantly change the magnetic property of Mn3Sn. As result, the value of remanent magnetization (M r) for the deformed sample (0.056 mB/f.u.) is about eleven times that for the pre-deformed sample (0.005 mB/f.u.), and the value of coercivity (H c) increases from 0 kOe (pre-deformed sample) to 6.02 kOe (deformed sample). Our findings provide a way to generate OWFM spin structure at room temperature and may give fresh ideas for creating antiferromagnetic materials with excellent physical properties.

In a wide strain rate range from 10−5 to 103 s−1, the deformation behavior of an Al-based nanocrystalline alloy was investigated. After fracture, the debris collected was used for statistical analysis, which is expected to reflect the profile of the fracture behavior of the alloy. The energy absorption of alloy at different strain rates was elucidated on account of mass distribution of debris. Based on the parameters obtained by the compression experiment at different strain rates, the numerical simulation experiment was carried out to evaluate the performance of Al-based nanocrystalline alloy as spacecraft shielding. The results suggest that Al-based nanocrystalline alloys have better shield performance than aluminum alloy under the identical areal density at velocity of 1–7 km/s. The better shield performance is attributed to high fracture strength, high hardness and low toughness of Al-based nanocrystalline alloy as compared with those of aluminum alloy.

Pyrolysis characteristics and mechanism of tobacco stem were studied by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS), thermogravimetric analyzer coupled with Fourier transform infrared spectrometry, and mass spectrometry (TG-FTIR and TG-MS) techniques. The composition of evolved volatiles from fast pyrolysis of tobacco stem was determined by Py-GC/MS analysis, and the evolution patterns of the major products were investigated by TG-FTIR and TG-MS. Py-GC/MS data indicated that furfural and phenol were the major products in low temperature pyrolysis, and these were generated from depolymerization of cellulose. Indene and naphthalene were the major products in high temperature pyrolysis. TG-FTIR and TG-MS results showed that CO, CO2, phenols, aldehydes, and ketones were released between 167ºC and 500ºC; at temperatures >500ºC, CO and CO2 were the main gaseous products.

Zinc finger nuclease (ZFN), which is a chimeric fusion structure between a Cys2-His2 zinc-finger protein (ZFP) and the cleavage domain of Fok I endonuclease, can be used to introduce targeted double-stranded breaks (DSBs). ZFN-mediated cleavage leads to mutations when double-stranded breaks are repaired by homologous recombination (HR) or nonhomologous end joining (NHEJ). In recent years, ZFNs are widely used in the fields of genetic research. In this review, the methodology and technical advantages of ZFNs were briefly discussed.

Land use/cover change is one of the three global environmental changes. The speeding land use/cover change process caused by the fast urbanization with significant economic development has remarkable influence on the urban environment. More and more attentions are paid on the effects of land cover changes on environment. NanHai District, which is located in the hinterland of Pearl River Delta, has a high intensive development on land use, for its advantageous location and highly developed economic. Accompanied with significant economic growth in last decade, NanHai District experienced a series of great changes in land use/cover change due to intensive human-induced activities. The most drastic change of land cover pattern was the transformation from dike-pond to other patterns, which results in eco-agriculture degradation and reduction of dike-pond. NanHai District is a typical represent of Pearl River Delta on land cover change. The data source of the research area mainly based on three phase of Landsat remote images. First, the method of FLAASH was used on the Landsat remote images for radiant correction, and then images were used for geometric correction with ENVI 4.5. Then, rivers and lake on the images were extracted and the edge was feathered. The Mahalanobis Distance supervised classification method combined with humancomputer interactive visual interpretation was used, and some field investigations were made to get the land cover pattern maps. Second, transfer matrix was generated by overlaying the maps of different issues. At last, ten index (Number of Patches, Patch Density, Largest Patch Index, Landscape Shape Index, Fractal Dimension Index-AW, Shannon's Diversity Index, Contagion Index, Patch Cohesion Index, Splitting Index) calculated with FRAGSTARS 3.3 software were use to describe the total situation and speed of land cover change, and spatial-temporal feature of landscape pattern changes during the last 19 years. The results of quantitative analysis of land cover structure and its change show that the utilization degree index of cropland, meadow & forestland, dike-pond etc. have increased significantly with urbanization process, especially cropland. This tendency has been slight since 2000. From then on, the information and location of each land cover pattern began to change frequently, and presented the spatial differentiation of land cover. The results of analysis of landscape characteristic index and gradients show that the land use changes in NanHai District could be mainly described by decreased diversity, fragmentation tendency and decreased of cropland.