The Mn cluster （Mn4CaO5） on the thylakoid luminal side of photosystem II （PSII） catalyzes the photosynthetic oxygen-evolving reaction, an essential process for life on Earth. In higher plants and ...green algae, the Mn cluster is surrounded by the membraneextrinsic proteins PsbO （33 kDa）, PsbP （23 kDa）, and PsbQ （17 kDa） （Murata and Miyao, 1985）.
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Grana thylakoids in plants comprise multiple, tightly appressed thylakoid membranes in the chloroplast, which greatly increase the area-to-volume ratio and significantly improve the ...ability of chloroplasts to capture light. Grana layers are stacked and interact through the stromal surface of proteins embedded in the grana membranes,
Room-temperature ferromagnetism with a Curie temperature higher than 380 K was studied in GaN： Mn thin films grown by metal-organic chemical vapor deposition. By etching artificial microstructures on ...the GaN： Mn layer, strong magnetic re- sponses were observed in the magnetic force microscopy （MFM） measurement, which revealed that the films were independ- ent of dopant particles and clusters. Numerical simulation on the data of atomic force microscope （AFM） and MFM measure- ments covering the whole microstructure validated the formation of long range magnetic order. This result excluded a variety of controversial origins of room-temperature ferromagnetism in the GaN： Mn and gave a strong evidence of our GaN： Mn as the intrinsic diluted magnetic semiconductor （DMS）. The forwarded method for accurate characterization of long range magnetic order could be applied to a wide range of DMS and diluted magnetic oxide （DMO） systems.
A detailed study is presented on magnetic, electrical and optical properties of Gal_xMnxN： Si film grown by metal organic chemical vapor deposition （MOCVD） with high-purity Sill4 as the Si dopant ...source. The room-temperature field dependence magnetization and zero-field-cooled （ZFC）/field-cooled （FC） measurements indicate that the film remains room-temperature ferromagnetism and it declines slightly after Si co-doping. However, room-temperature Hall measurements indicate that the electrical property of the film improves distinctly compared with Gal-xMnxN. Cathode luminescence （CL） measurements show an obvious enhancement in luminous property and different peak strength changes at three different positions. Therefore, we demonstrate that Fermi level and the electron structure of Mn atoms will change with variation of the impurities co-doped and the intrinsic defects and this may be related with room-temperature ferromagnetism and the other corresponding properties of the film.
Flexible and thin energy storage devices have attracted enormous attentions. An easy and large-scale method has been employed to fabricate flexible and interwoven N, P dual-doped carbon ...fibers/graphitic carbon nitride (huCP/g-C3N4) using filter paper as a precursor. The huCP/g-C3N4 composite as self-supporting anode for lithium ion batteries exhibits high reversible capacities of 1030 mAh g−1 after 1000 cycles at 1 A g−1 and 360 mAh g−1 after 4000 cycles at 10 A g−1 along with excellent rate performance (133 mAh g−1 at 30 A g−1). For sodium ion batteries, huCP/g-C3N4 as anode delivers high reversible capacities of 345 mAh g−1 after 380 cycles at 0.1 A g−1 and 110 mAh g−1 after 4000 cycles at 1 A g−1. This excellent electrochemical performance can be attributed to the high contents of doped N and P in huCP/g-C3N4 and graphitic carbon nitride network, which not only create more defects and active sites but also expand the layer planes and provide interconnected conductive network.
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Abstract Solid‐state sodium metal batteries have attracted wide attention due to their high energy density, remarkable safety, and abundant sodium resources. However, the growth of Na dendrites and ...poor interfacial contact between Na metal anode and Na 3 Zr 2 Si 2 PO 12 (NZSP) solid‐state electrolytes severely limit their practical application. Herein, a wettable liquid metal (GaIn) interlayer significantly reduces the interfacial resistance and avoids the formation of voids at the Na/NZSP interface. Moreover, the Ga 4 Na and NaIn alloys at the interface caused by the spontaneous reaction of GaIn with Na metal enhance the bond of NZSP with Na anode, which provides a continuous Na + diffusion pathway and homogeneous Na + flux to suppress Na dendrite growth. The symmetric cell can cycle stably for over 6500 h at 0.05 mA cm −2 and over 3000 h at 0.1 mA cm −2 , with a critical current density of 0.8 mA cm −2 at 25 °C, and the interfacial resistance is significantly reduced to 21.6 Ω from 1095.1 Ω. The full cell coupled with NaNi 1/3 Fe 1/3 Mn 1/3 O 2 also shows outstanding cycling performance, maintaining 85.1% capacity after 100 cycles at 0.5 C. This work demonstrates that the liquid metal interlayer has a large potential for the practical application of solid‐state metal batteries.
Person Re-identification (re-id) aims to match people across non-overlapping camera views in a public space. It is a challenging problem because many people captured in surveillance videos wear ...similar clothes. Consequently, the differences in their appearance are often subtle and only detectable at the right location and scales. Existing re-id models, particularly the recently proposed deep learning based ones match people at a single scale. In contrast, in this paper, a novel multi-scale deep learning model is proposed. Our model is able to learn deep discriminative feature representations at different scales and automatically determine the most suitable scales for matching. The importance of different spatial locations for extracting discriminative features is also learned explicitly. Experiments are carried out to demonstrate that the proposed model outperforms the state-of-the art on a number of benchmarks.
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•Low-cost and practical anthracite-derived carbon anode has been prepared.•The microstructure and performance strongly rely on the pyrolysis temperature.•The carbon exhibits superior ...electrochemical performance in LIBs and KIBs.•The charge storage is mainly ions adsorptions mechanism.
Graphite is limited to apply in large-scale energy storage system due to its high cost in lithium ion batteries and poor potassium storage performance in potassium ion batteries. Herein, a low-cost and mass-production of carbon as anode for lithium/potassium ion batteries has been prepared through one-step and low-temperature pyrolysis of anthracite. High yield of carbon and low pyrolysis temperature can greatly reduce cost of carbon anode using anthracite as raw material. Detailed investigation on microstructure and electrochemical performance indicates that the carbon with order and disorder hybrid structure exhibits the best electrochemical performance. Compared with the commercial graphite anode, the low-cost carbon displays the approximate capacity of 384.5 mAh g−1 at 100 mA g−1 in lithium ion batteries and superior capacity and cycling stability in potassium ion batteries. The adsorption and intercalation mechanism caused by the hybrid structure contributes to the enhanced capacity and cycling stability in lithium/potassium ion batteries. The abundant micropores and defects act as active sites for efficient Li+/K+ storage. The low-cost carbon is highly expected to be a promising anode to the large-scale production for high performance lithium/potassium ion batteries.
Porous NiO/Ni foam electrode is fabricated by a simple two-step method. Firstly, nickel hydroxide hydrate nanoflakes are deposited on Ni foam via a chemical liquid deposition (CLD) method. Then ...NiO/Ni architecture is obtained by subsequent graft growth in air atmosphere at 350°C. Galvanostatic battery testing shows that NiO electrode exhibits fine capacity retention and good rate performance. It exhibits high initial discharge and charge capacity of 1.94 and 1.36mAhcm−2, maintaining of 1.41 and 1.38mAhcm−2 after 140 cycles under a discharge/charge rate of 0.4C. It delivers high discharge capacity retention of 70% (comparing with that of 0.2C) even at a high rate of 2.5C. After that, the discharge capacity can gradually resume along with the decrease of discharge/charge rate, showing capacity retention of 105% when lowering the discharge/charge rate to 0.2C. The fine electrochemical performance of NiO/Ni is due to the maintenance of porous architecture and the prevention of active nano-sized NiO from aggregation in cycling, which is relevant to both the interweaved structure of NiO nanoflakes and the graft growth between NiO and Ni.
Person re-identification (re-id) aims to match people across non-overlapping camera views in a public space. This is a challenging problem because the people captured in surveillance videos often ...wear similar clothing. Consequently, the differences in their appearance are typically subtle and only detectable at particular locations and scales. In this paper, we propose a deep re-id network (MuDeep) that is composed of two novel types of layers - a multi-scale deep learning layer, and a leader-based attention learning layer. Specifically, the former learns deep discriminative feature representations at different scales, while the latter utilizes the information from multiple scales to lead and determine the optimal weightings for each scale. The importance of different spatial locations for extracting discriminative features is learned explicitly via our leader-based attention learning layer. Extensive experiments are carried out to demonstrate that the proposed MuDeep outperforms the state-of-the-art on a number of benchmarks and has a better generalization ability under a domain generalization setting.
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