MnO2 prepared by hydrothermal method and electrochemical performance as anode for lithium-ion battery

Two α-MnO₂ crystals with caddice-clew-like and urchin-like morphologies are prepared by the hydrothermal method, and their structure and electrochemical performance are characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), galvanostatic cell cycling, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). The morphology of the MnO₂ prepared under acidic condition is urchin-like, while the one prepared under neutral condition is caddice-clew-like. The identical crystalline phase of MnO₂ crystals is essential to evaluate the relationship between electrochemical performances and morphologies for lithium-ion battery application. In this study, urchin-like α-MnO₂ crystals with compact structure have better electrochemical performance due to the higher specific capacity and lower impedance. We find that the relationship between electrochemical performance and morphology is different when MnO₂ material used as electrochemical supercapacitor or as anode of lithium-ion battery. For lithium-ion battery application, urchin-like MnO₂ material has better electrochemical performance.     

电力供电大楼机房能耗监测与分析系统研究

针对提倡节能减排的社会背景，设计实现了面向电力供电大楼机房能耗监测与分析系统，基于现有的机房能耗数据资源，通过对机房能耗数据多方面的监测以及科学化的分析，为管理者更好地制定节能措施提供决策支持。系统功能分为能耗环境监测、能耗行为分析、节能改造建议、节能效果评估4个子模块；利用GESD算法设计了能耗异常检测方法，利用SSH框架实现了B/S架构；在数据展示方面利用了Extjs、BIRT报表2种技术，利用POI实现了导出Excel格式的能耗数据文件。实际应用表明，该系统为管理者制定节能减排措施提供了帮助。     

Evaluation of a large dish‐type concentrator solar lighting system for underground car park

To utilize solar energy more efficiently and reduce lighting power consumption in underground public spaces such as car park, a large dish‐type concentrator solar lighting system is put forward along with its evaluation, which is a unique design to apply a laminated layer of beam split thin‐film coating and thin‐film solar cells onto the dish reflector. The collected sunlight is split into 2 parts, one being reflected into a fiber optical bundle and transmitted for daylighting, while the rest being absorbed by solar cells for electricity generation as the other way to replenish daylighting. A set of 4 solar lighting systems using 3.28‐m diameter dish are designed to meet the lighting requirement in a 1771‐m² underground car park. A mathematical model is adopted to calculate the output power and conversion efficiency of solar cells distributed on the parabolic dish surface. The indoor illuminance distribution is given by lighting simulation. The results indicate that the average daylight illuminance in the car park can vary between 62.7 and 284 lx on February 25, 2016 and between 62.7 and 353 lx on August 17, 2016 for 2 chosen days, respectively. For the presented design, the electricity produced by solar cells is just enough to power light‐emitting diodes for lighting meeting a criterion at night. Considering about 19% conversion efficiency of solar cells and the efficacy of 129.5 lm/W of light‐emitting diodes, the hybrid solar lighting system can have about 40% utilization ratio of solar energy, so it can be concluded that a sufficient lighting provision can be provided by the proposed large dish‐type concentrator solar lighting system for applications in underground car park.     

面向复杂系统创新的TRIZ与DFSS集成应用模式

针对目前现有创新方法在解决复杂系统问题时出现问题定位不准,分析不彻底,难以产生创新性方案,以及复杂系统设计领域尚缺乏系统的方法论的问题.研究创新设计理论(Theory of Innovation Problem Solving,TRIZ)与六西格玛设计(Design For Six Sigma,DFSS)集成方法,根据复杂系统特点在不同设计阶段动态地集成各种工具,以完善的需求管理方法实现设计需求的无偏转化,运用AFD等工具在设计早期进行系统功能失效预测,集成多冲突问题与TRIZ工具实现概念设计阶段创新性求解,进而建立面向复杂系统创新的T-DFSS模型.最后以船舶模块化可倒栏杆创新设计实例验证该集成模式的有效性.     

Activation of the Complement System on Human Endothelial Cells by Urban Particulate Matter Triggers Inflammation-Related Protein Production

Exposure to particulate matter (PM) is becoming a major global health issue. The amount and time of exposure to PM are known to be closely associated with cardiovascular diseases. However, the mechanism through which PM affects the vascular system is still not clear. Endothelial cells line the interior surface of blood vessels and actively interact with plasma proteins, including the complement system. Unregulated complement activation caused by invaders, such as pollutants, may promote endothelial inflammation. In the present study, we sought to investigate whether urban PM (UPM) acts on the endothelial environment via the complement system. UPM-treated human endothelial cells with normal human serum showed the deposition of membrane attack complexes (MACs) on the cell surface via the alternative pathway of the complement system. Despite the formation of MACs, cell death was not observed, and cell proliferation was increased in UPM-mediated complement activation. Furthermore, complement activation on endothelial cells stimulated the production of inflammation-related proteins. Our results revealed that UPM could activate the complement system in human endothelial cells and that complement activation regulated inflammatory reaction in microenvironment. These findings provide clues with regard to the role of the complement system in pathophysiologic events of vascular disease elicited by air pollution.     

The Effect of Tb80Fe20/Al Co-adding on Coercivity and Thermal Stability in Sintered Nd–Fe–B Magnets

Journal of Superconductivity and Novel Magnetism - The influence of Tb80Fe20/Al co-adding on coercivity and temperature stability of sintered Nd–Fe–B magnets was studied. Compared with...     

Application of distributed motion estimation for swarm MAVs in a GPS-restricted environment based on a wireless sensor network

The Journal of Supercomputing - To meet the requirements for motion estimation of a swarm of micro-aerial vehicles in a GPS-restricted environment, a distributed motion estimation algorithm is...     

Path planning of nanorobot: a review

Microsystem Technologies - Efficient and accurate path planning in a complex biological environment have become a challenge for nanorobot research. This paper first reviews the current path...     

Self-defective ZnS mediated charge transfer for bran-new inter-step mode with boosted photoactivity and enhanced photostability

The appropriate interfacial contact and charges transfer mode of heterojunction photocatalysts were critical for high-efficiency hydrogen production. Inter-step mode heterojunction composite had advantages of enhanced visible-light response, improved charge space separation rate, increased electron utilization, which could also protect catalyst anode from photocorrosion. Zinc-vacancy-rich ZnS decorated CdS heterojunction photocatalyst with inter-step mode was constructed in order to fundamentally enhance photocatalytic performance and overcome photocorrosion of CdS. The charge transfer mode was modulated from pervasive type-II to bran-new inter-step mode by defect engineering. Zinc vacancies functioned as acceptor level for charge separation and up-shifted conduction and valance band energy of ZnS. The defective engineered CdS/ZnS heterojunction displayed a reduced over-potential and enhanced photocatalytic activity. The optimal photocatalytic hydrogen production rate for CdS/ZnS reached 42.1 mmol?g^?1 under visible light without any co-catalyst. An apparent quantum yield (AQY) of 38.75% at 450 nm was achieved, which was 269.3 and 71.9 times higher than pristine zinc-vacancy-rich ZnS and CdS, respectively. Meanwhile, holes aggregated on the surface of CdS were blocked and the oxidation corrosion process was suppressed. The charge transfer mechanism and kinetics of charge transfer and separation in inter-step mode heterojunction photocatalysts were investigated and discussed. This work will accelerate practical applications of photocatalysis with inter-step mode and give deep insights into understanding how inherent acceptor levels play a role in designing defect-engineered semiconductor with enhanced photocatalytic performance.     

Study on the uniformity of water film in a transpiring wall reactor for supercritical water oxidation

A three-dimensional computational fluid dynamic model of a transpiring wall reactor for supercritical water oxidation has been built to optimize the uniformity of water film. Results show that the temperature and species distributions at the nozzle outlet deviate from the reactor centre. The inner wall of the porous tube near the transpiring water injection tube displays low temperatures, while high temperatures are recorded far from the injection tube. The circumferential temperature distribution on the inner wall of the porous tube is uneven. This phenomenon is due to the uneven injection of the transpiring water, leading to the uneven protection of the water film and local overheating of the porous wall. The injection velocity of the transpiring water significantly decreases when the number of injection tubes is increased, and the circumferential velocity and temperature distributions on the porous wall gradually become even. Moreover, high pressure drops across the porous wall at low porosities are useful for the uniform injection of the transpiring water. This characteristic is also conducive to obtaining a more uniform water film protection.