TY - JOUR
AU - Xu, Xiuling
AB - PHYSICS Mass production of metre-sized single-crystal graphene is now possible The growth of large-area single-crystal graphene (SCG) materials economically has long been the Holy Grail in graphene science and technology. Recently, joint research of Kaihui Liu, Dapeng Yu and Enge Wang from Peking University and co-workers developed a new strategy to realize the ultrafast epitaxial growth of metre-sized SCG on industrial Cu foil (see Fig. 1). It is very likely that this approach can be scaled up to achieve exceptionally large and high-quality graphene films with single crystallinity, and thus realize various industrial-level applications at a low cost. [Xu X et al. Sci Bull 2017; 62: 1074–80] Figure 1. Open in new tabDownload slide Schematic diagram of the growth process of metre-sized SCG. Published in Sci Bull 2017; 62: 1074–80. Figure 1. Open in new tabDownload slide Schematic diagram of the growth process of metre-sized SCG. Published in Sci Bull 2017; 62: 1074–80. PHYSICS Tip point contact: turn non-superconducting Weyl semimetal to topological superconductor candidate Topological Weyl semimetal possesses the gapless bulk nodal points with definite chirality and Fermi arc surface states. Recently, Jian Wang and co-workers from Peking University discovered tip-induced superconductivity on the Weyl semimetal TaAs single crystal by hard (tip) point contact measurements. The experimental observations from the tip–TaAs interface (see Fig. 2) show unconventional superconducting features, which could be theoretically interpreted by the existence of a mirror-symmetry-protected topological superconducting phase. This work demonstrates an effective method to realize unconventional superconductivity around hard-point contact regions on non-superconducting topological Weyl semimetals. [Wang H et al. Sci Bull 2017; 62: 425–39] Figure 2. Open in new tabDownload slide Point contact measurements between a PtIr tip and the TaAs single crystal. (a) Temperature dependence of zero-bias point contact resistance showing typical superconducting transition. Inset: schematics of the point contact spectra measurement configuration. (b) Normalized dI/dV spectra at selected temperatures from 0.5 to 6.0 K. Inset: Zoom-in of the normalized zero-bias conductance peaks. The darkest blue line denotes T = 0.5 K. Figure 2. Open in new tabDownload slide Point contact measurements between a PtIr tip and the TaAs single crystal. (a) Temperature dependence of zero-bias point contact resistance showing typical superconducting transition. Inset: schematics of the point contact spectra measurement configuration. (b) Normalized dI/dV spectra at selected temperatures from 0.5 to 6.0 K. Inset: Zoom-in of the normalized zero-bias conductance peaks. The darkest blue line denotes T = 0.5 K. PHYSICS Superconducting pairing mechanism in quasi-one-dimensional alkali chromium arsenides A new family of quasi-1D superconductors A2Cr3As3 (A = K, Rb, Cs) discovered at ambient pressure with Tc up to 6.1 K has attracted much attention. Recently, Yi Zhou of Zhejiang University and co-workers proposed a minimal model for these compounds in terms of molecular orbital states and by using symmetries. Theoretically, they found that strong Hund's coupling will give rise to spin-triplet pairing and unveil an unconventional superconductor. The spin-triplet scenario was consistent with existing experiments. [Zhou Y et al. Sci Bull 2017; 62: 208–11] CHEMISTRY Temperature-dependent optical response for WS2/MoS2 monolayer heterostructures 2D heterostructures have been investigated as a hot spot due to their distinct opto-electronic properties. Recently, Zheyu Fang and co-workers at Peking University measured Raman and photoluminescence spectra of the vertically stacked WS2/MoS2 monolayer heterostructure within a temperature range of 300–642 K. The results revealed their temperature dependency, which corresponds to the theories of charge transfer between two materials and direct-to-indirect band-gap transition. This demonstration provides an excellent platform to study the interface interactions of 2D materials. [Hu Z et al. Sci Bull 2017; 62: 16–21] AGRICULTURAL SCIENCES A gene from wild soybeans contributes to 100-seed weight in cultivated soybeans Soybean is an important crop for oil and protein resources. Its yield is contributed by 100-seed weight and other factors. Through analysis of a population derived from a cross between a wild soybean and a cultivated soybean, Jin-Song Zhang's group and Shou-Yi Chen's group from the Institute of Genetics and Developmental Biology, CAS, and Weiqun Man's group from Heilongjiang Provincial Academy of Agricultural Sciences identified a variant of protein phosphatase 2C (PP2C-1) from wild soybean. This variant enhanced soybean seed weight by activating plant hormone brassinosteroid pathway. Soybean cultivars that do not contain PP2C-1 may be improved for 100-seed weight by introducing this variant. [Lu X et al. Mol Plant 2017; 10: 670–84] MOLECULAR BIOLOGY & GENETICS The 5-methylcytosine promotes mRNA export Chinese researchers from the Beijing Institute of Genomics, CAS, reported that m5C promotes mRNA export. Yun-Gui Yang and his colleagues developed a high-throughput sequencing technique for mapping RNA m5C and discovered the distributive features of m5C, i.e. enrichment near translation-initiation sites. They further identified that NSUN2 is the main mRNA m5C methyltransferase and ALYREF serves as the first m5C binding protein—two members critically implicated in the modulation of m5C-promoted mRNA export (see Fig. 3). This work reveals the biological significance of m5C in RNA processing. [Yang X et al. Cell Res 2017; 27: 606–25] Figure 3. Open in new tabDownload slide Schematic model of mRNA export promoting by 5-methylcytosine. Figure 3. Open in new tabDownload slide Schematic model of mRNA export promoting by 5-methylcytosine. BIOLOGY & BIOCHEMISTRY Control gene activation in human pluripotent stem cells Activating gene expression at the right time and place has been difficult, particularly in stem cells. Jie Na and co-workers from Tsinghua University engineered a powerful and controllable dCas9-VPR (iVPR) transcriptional activator system and inserted it into a safe harbour location in the human genome to create an iVPR pluripotent stem cell line (see Fig. 4). They used iVPR to enhance NANOG gene expression to generate naive state pluripotent stem cells, and showed that multiple genes can also be activated at the same time by simply transfecting sgRNA plasmids and adding the inducing drug. The iVPR system can greatly facilitate gene function studies and high-throughput screening in human stem cells. [Guo J et al. Protein Cell 2017; 8: 379–93] GEOSCIENCES New advances on the Cretaceous greenhouse palaeoclimate The Cretaceous (145–66 million years ago) is the youngest prolonged greenhouse climate interval in geological history. Understanding the Cretaceous palaeoclimate is essential for a more accurate prediction of future global climate, sea-level rise and environmental changes in a prospective ‘Cretaceous-like’ greenhouse Earth. Six papers including two review papers were published in a topic section ‘Cretaceous greenhouse palaeoclimate’, sponsored by the IGCP609 project, and edited by Xiumian Hu, Michael Wagreich and Benjamin Sames. The scientific topics discussed in those papers included Cretaceous greenhouse climate, sea-level change, oceanic anoxic events and geobiological evolution. [Hu X et al. Sci China Earth Sci 2017; 60: 1–4] Figure 4. Open in new tabDownload slide The iVPR human pluripotent stem cell system. Figure 4. Open in new tabDownload slide The iVPR human pluripotent stem cell system. MATERIALS SCIENCE Light magic: from metal colloids to free-standing, conductive metallic thin film A novel approach that allows the creation of free-standing, conductive metallic thin film from metal colloids was recently reported by Jiawen Hu and co-workers at Hunan University. They found that light can weld adjacent Au and Ag nanoparticles because their very small interparticle gaps can be easily filled by light-accelerated Ostwald ripening (see Fig. 5). This finding offers a solution-processed strategy to the preparation of conductive electrode for functional electronic and optoelectronic devices. [Hu JW et al. Sci China Mater 2017; 60: 39–48] INFORMATION SCIENCE A new method to design the soft docking mechanism for micro/small satellites An evaluation criterion of a successful docking based on an accurate theoretical model is significant for the design of the soft docking mechanism. Xiang Zhang and co-workers at National University of Defense Technology have proposed such an evaluation criterion by considering the operational principle of the capturing mechanism used in micro/small satellites. The main parameters of the soft docking were analysed and designed based on the proposed criterion. This work provides a guideline to improve the properties of soft docking for micro/small satellites. [Zhang X et al. Sci China Inf Sci 2017; 60: 050204] Figure 5. Open in new tabDownload slide The combination of self-assembly of nanoparticles at fluid interface and a light welding process allows the creation of highly interconnected, metallic thin film with high flexibility, robustness and conductivity from metal colloids. Figure 5. Open in new tabDownload slide The combination of self-assembly of nanoparticles at fluid interface and a light welding process allows the creation of highly interconnected, metallic thin film with high flexibility, robustness and conductivity from metal colloids. © The Author(s) 2017. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is properly cited. for commercial re-use, please contact journals.permissions@oup.com © The Author(s) 2017. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
TI - Editors' selection of papers from China's academic journals
JF - National Science Review
DO - 10.1093/nsr/nwx112
DA - 2017-07-01
UR - https://www.deepdyve.com/lp/oxford-university-press/editors-selection-of-papers-from-china-s-academic-journals-BAabA0kxDf
SP - 515
EP - 517
VL - 4
IS - 4
DP - DeepDyve
ER -