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Highly conductive Ag is proven effective to improve the electrochemical performance of Li3VO4. Ag@Li3VO4 composite with unique architecture of Ag nanoparticles embedded homogeneously in Li3VO4 matrix is prepared by a facile intermediate solution method. The Ag@Li3VO4 delivers high initial discharge and charge capacities of 651 and 479 mAh g−1 at a specific current of 0.15 A g−1, maintaining of 498 and 492 mAh g−1 after 150 cycles. Superior rate capability (364 mAh g−1) can be achieved at 1.5 A g−1, with more than 5 times improvement compared the one without Ag decoration. Herein, conductive but inert Ag is found facilitating fast Li+ ion storage of the Li3VO4 owing to enhanced electronic conductivity, Li ion diffusion, and structure stability, distinctly improving cycle stability and rate performance. Published version

Li3VO4@LiVO2 composite with a specific architecture of Li3VO4 crystals homogeneously embraced by LiVO2 matrix is fabricated via an intermediate solution approach with subsequent sintering. In the Li3VO4@LiVO2, the small-sized Li3VO4 and the weak crystallized LiVO2 render self-enhanced fast lithium ion diffusion and high electrical conductivity, which trigger high pseudocapacitive charge storage and result in superior cycle stability and rate capability. The Li3VO4@LiVO2 delivers initial discharge and charge capacities of 569 and 448 mAh g−1 at a specific current of 0.15 A g−1. The discharge and charge capacities exhibit no attenuation in cycling, maintaining at 468 and 471 mAh g−1 after 100 cycles. After 70 cycles at various specific currents from 0.1 to 2.0 A g−1, the Li3VO4@LiVO2 recovers high reversible capacity of 478 mAh g−1 when reverting the specific current to 0.1 A g−1.

Acicular NiS on Ni foam was successfully prepared via a low temperature sulfuration method, using Ni foam as raw material. The as-prepared NiS-Ni electrode exhibits superior electrochemical performance as freestanding anode for half-cell and full-cell sodium-ion batteries. At a specific current of 0.03 A g −1 , it delivers initial discharge and charge capacities of 1368.8 and 813.6 mAh g −1 , maintaining of 504.8 and 497.4 mAh g −1 after 50 cycles. After 50 cycles at various specific current from 0.05 to 0.4 A g −1 , the discharge capacity can restore to 570.6 mAh g −1 when reverting specific current to 0.05 A g −1 . When matching with Na 3 V 2 (PO 4 ) 3 cathode, the full cell shows charge and discharge capacities of 172.8 and 163.5 mAh g −1 after 100 cycles at a specific current of 0.05 A g −1 .

3D porous CuS@Cu composite is prepared via a facile H 2 O 2 aided electrochemical corrosion method, which shows prominent electrochemical performance as freestanding electrode for Li-ion batteries. It delivers no capacity fading at a specific current of 0.5 A g −1 , showing discharge/charge of 845/834 mAh g −1 after 500 cycles. After 50 cycles at various specific current from 0.1 to 1.5 A g −1 , the CuS@Cu electrode can still exhibit no capacity fading over 300 cycles at 2 A g −1 , delivering discharge capacity of 414 mAh g −1 .

Temperature dependent fabrication of NiCr 2 O 4 is studied and the application of the as-prepared NiCr 2 O 4 in both half-cell with Li metal anode and full-cell with LiFePO 4 cathode are assessed. When mixing with natural graphite (NG), the NiCr 2 O 4 obtained at 550 °C can deliver initial charge and discharge capacities of 795 and 1275.5 mAh g −1 at a specific current of 150 mA g −1 , maintaining of 939 and 955 mAh g −1 after 140 cycles. In contrast, after 140 cycles at the same specific current, the NiCr 2 O 4 obtained at 450 °C and 650 °C can maintain charge/discharge capacities of 800/814 and 523/528 mAh g −1 , respectively. When matching with a LiFePO 4 cathode, The NiCr 2 O 4 /NG (obtained at 550 °C) electrode delivers initial discharge capacity of 285 mAh g −1 , which maintains of 106 mAh g −1 after 50 cycles at a specific current of 100 mA g −1 .

Molten Salt Reactor (MSR) has been recognized as one of the Next Generation Nuclear Power systems. Most MSR concepts are the variants evolved from the ORNL’s Molten-Salt Breeder Reactor (MSBR) which employs Molten-Salt as both fuel and coolant, and normally graphite is used as moderator. Many evaluations have revealed that such concepts have low breeding ratio and might present positive power coefficient. Facing these impediments, TMSR (Thorium Molten Salt Reactor) with redesigned lattice is proposed in this paper. Based on comprehensive investigation and screening, important lattice parameters including molten salt fuel composition, solid moderator material, lattice size, structure and lattice P/D ratio (lattice pitch to channel diameter) are redesigned. In this paper, new composition of fuel salt without BeF2, which is also recommend for Molten Salt Fast Reactor (MSFR), is employed instead of LiF-BeF2-ThF4-UF4 adopted in the design of single fluid MSBR. The new fuel composition makes TMSR to benefit from the increased solubility for actinides (e.g. Th4, UF4). Moreover, due to the decent slowing-down power and neutron multiplication effect by (n,2n) reaction of beryllium, BeO is employed as moderator to improve neutron economy instead of graphite. To avoid corrosion on the one hand, Ceramic cladding (e.g. SiC) is introduced to separate the flowing liquid fuel and fixed solid moderator. More importantly, ceramic cladding is capable of maintaining a stable flow channel and supporting the core structure on the other hand. Concerning neutron spectrum, P/D ratio is an important parameter indicating the volume fraction of fuel in the lattice. In order to obtain a suitable spectrum for better breeding and safety features, lattice size and P/D ratio have been optimized for TMSR. Furthermore, since online reprocessing capability and refueling control are key parameters influencing depletion behavior which concerns the sustainability of the reactor system, these issues are also discussed in this paper. Simulation of the redesigned TMSR system is performed to evaluate the outcomes of the lattice parameters optimization. SONG/TANG-MSR codes system is applied in the simulation, which is independently developed by Shanghai Nuclear Engineering Research & Design Institute (SNERDI). A traditional core model with LiF-BeF2-ThF4-UF4 fuel and graphite moderator is also evaluated by the codes for reference. Thanks to the optimized lattice parameters and as consequences of the redesigned lattice, TMSR has achieved a high breeding ratio close to 1.13. With a proper reprocessing and refueling strategy, the doubling time of TMSR can be shortened to about 15 years. Meanwhile a negative power coefficient is still maintained. Based on this lattice design, TMSR will have excellent performance on safety and sustainability.

The past decade has witnessed the large shipments of Ethernet switches and IP routers. The wide availability of commodity Ethernet ASICs and the publicly open interoperable Ethernet/IP network standards have made Ethernet/IP equipment the preferred deployment option in the campus, data center, and mobile service operator’s 3G/4G LTE backhaul network. In this paper, we present an end-to-end Ethernet Transport Network (ETN) framework which features multi-service access, deterministic forwarding latency, hard traffic isolation, hierarchical traffic multiplexing, flexible and adjustable L1/L2/L3 forwarding, and multi-layer OAM mechanism. We envision ETN to be a unified solution for the future 5G mobile transport, metro, and data-center interconnects (DCI) network. In the end, we present the preliminary evaluation of our ETN prototype switch boxes implemented using commercial FPGAs and share our future vision for ETN evolution.

Graphene and amorphous carbon decorated β-Ga2O3 nanoparticles (β-Ga2O3@G/C) were fabricated via facile freezing-dry approach and subsequent sintering treatment. In the β-Ga2O3@G/C, β-Ga2O3 nanoparticles facilitate the lithium ion diffusion, and dual carbon decoration promotes the electron transfer, triggering high pseudocapacitive contribution for charge storage. The pseudocapacitive charge storage for the fresh electrode is 61.7%, reaching 62.5% after 50 cycles, and 66.7% after 100 cycles. Stable pseudocapacitive charge storage also leads to improved cyclability. The β-Ga2O3@G/C electrode exhibits high charge/discharge capacity of 517.9 and 521.8 mAh g−1 after 100 cycles at 0.2 A g−1, and 376.7/379.9 mAh g−1 after 150 cycles at 0.5 A g−1, respectively.

Fundamental insights into Li storage mechanism in α-Ga2O3 allow manipulating materials with improved electrochemical performance. Here, conversion reactions coupled with alloying/dealloying process are uncovered for Li storage in α-Ga2O3 anode, on the basis of ex-situ XRD, XPS, SAED and EDS mapping results. Specifically, both processes are part of irreversible. α-Ga2O3 decorated with amorphous carbon and graphene (α-Ga2O3@C@G) and nitrogen doping are successfully fabricated via a facile approach, showing distinctly improved performance compared with pristine α-Ga2O3 and α-Ga2O3 decorated with graphene (α-Ga2O3@G). In the Ga2O3@C@G, dual carbon improves the electronic conductivity and facilitates electrochemical reconstruction of the Ga2O3@C@G upon cycling that renders high lithium ion diffusion, giving rise to enhanced capacitive contribution for lithium storage. As a result, the Ga2O3@C@G exhibits high discharge/charge capacity of 458/447.3 mAh g−1 after 50 cycles at 0.1 A g−1, with capacitive contribution of 59.2% for lithium ion storage at a scan rate of 1 mV s−1.

We have developed the 293-group cross-section library SONGLIB with complete reaction pathes, broad-spectrum solving ability and wide range isotopes, which is adopted in the lattice code SONG, the next generation reactor lattice calculation and analysis code. SONGLIB provides the multi-group data for the transport calculation, resonance calculation and burnup calculation of SONG. So the precision and reliability of data is very important. However, the size of the data is very large and there are still a lot of personal factors in determination of the processing parameters and methods. In order to evaluate the library, it’s necessary to carry out the test work comprehensively. Amount of test work is then undertaken based on three kinds of reactors such as pressurized water reactor with UO2 fuel, sodium cooled fast reactor and new-type molten salt reactor with none-beryllium core. In order to test the adaptivity of the library, 39 cases are designed totally, changing the fuel composition, the absorber compositon, the burnup depth and the working temperature. Only the results of a few cases are given in details to shorten the length of this article. For comparison, the Monte Carlo code MCNP is chosen and the library source of evaluated nuclear data is ensured to be the same. The model that has been calculated is simple, the cell with “fuel-cladding-modulator” the three-layer structure and total reflection boundary for the aim of minimizing the differences between the codes. From the macroscopic angle, the results of infinite multiplication factor fit well with each other in total. From the microscopic angle, the absorption rate for actinides, fission products and absorbers, the fission rate for fissile isotopes and scattering rate for moderators are compared with that of MCNP whose output is normalized to the actual cell power. The difference between the reaction rates for most isotopes can be neglected. But there still exist some obvious differences for some isotopes whose resonance effect should have been considered, such as Fe56, ZrNat and W, which might affect the macoscopic results to some extent. As a conclusion, the data of SONGLIB can be expected with high precision and reliability. And SONGLIB is adapted in solving various problems for reactors with different spectrum, depth of burnup, operation condition or fuel cycling. Nevertheless, there still exist some factors that may affect the final results during the process and use of the library, which should be paid attention to while taking a further step in optimizing and updating the library.

In order to improve the breeding ratio and core safety, new thorium molten salt reactor (TMSR) core is designed. The new designed TMSR core is composed of hexagon moderator elements, which contain SiC tube to form a central fuel channel and employs BeO as moderator. The composition of the fuel salt, adopted in this core, is also optimized. Based on this core design, steady state and transient safety characteristic of TMSR are preliminarily analyzed using coupled multi-physics code. Power/temperature distribution and reactivity coefficients are analyzed for the steady state core, which demonstrated that the core has flat temperature distribution and large negative power coefficients at all power level. Transient simulations are carried out for power start-up, pump speed variation, loss of heat sink and so forth, the temperature and power response are also analyzed. The results indicate that the TMSR core power and temperature are closely related to the control rod position, velocity of flow and composition of fuel salt, and the new designed TMSR has excellent performance of safety under various operating conditions.

Multi-group cross section library is the basic condition for lattice calculation, which provides the necessary nuclear data parameters. The multi-functional lattice code SONG (Si et al. in Nucl Power Eng 35:111–115, 2014. doi: 10.13832/j.jnpe.2014.S2.0112 ; Chen et al. in Nucl Power Eng 35:127–130, 2014. doi: 10.13832/j.jnpe.2014.S2.0127 ) is developed to adapt to the research demands of different types of new reactors, especially the fourth generation (GEN-IV) reactors (Cerullo and Lomonaco in Nucl Fuel Cycle Sci Eng, 2012. doi: 10.1533/9780857096388.3.333 ; Giorgio et al. in Energy Policy 61:1503–1520, 2013. doi: 10.1016/j.enpol.2013.06.101 ). The corresponding multi-group cross section library of SONG (SONGLIB) is well designed with much effort considering the next generation reactors’ new feature in material, spectrum, burnup depth, etc. Therefore, the burnup chain (Maria and Jaakko in Nucl Sci Eng 164:140–150, 2010. doi: 10.13182/NSE09-14 ), energy group structure (Tholakele et al. in Ann Nucl Energy 80:279–292, 2015. doi: 10.1016/j.anucene.2015.01.038 ), and reaction path should be specially considered. The library SONGLIB is processed with the Evaluated Nuclear Data File (ENDF), nuclide data auxiliary processing code NJOYBAT (Si et al. 2014), and library management code MANLIB (Si et al. 2014). A series of verification work of SONGLIB is then carried out, and the calculated results are satisfied.

TMSR fuel lattice was reevaluated by varying the P/D ratio (Ratio of Lattice Pitch to Channel Diameter) and Lattice Size (Pitch); an in-house developed computer code named SONG/TANG-MSR was used to calculate the key TMSR parameters such as core reactivity, conversion or breeding ratio and power reactivity coefficient. The optimized lattice was recommended with trade off of the above key parameters, which can satisfy the requirements of Sustainability and Safety.Copyright © 2014 by ASME