高原地区二甲醚燃烧器的选型研究

二甲醚作为清洁能源,不仅可以解决我国"缺油、少气"的能源现状,而且可以减少对环境的污染。二甲醚燃烧器是将二甲醚与空气中的氧气充分混合燃烧后转变为热能的装置。主要研究二甲醚燃烧器在高原地区使用时修正系数的计算过程,以及二甲醚燃烧器在高原地区的选型方法。为二甲醚燃烧器在高原地区的应用提供了理论基础。     

基于ARM的微型打印机研究与设计

本文介绍了基于ARM的微机打印机的硬件、软件设计与实现。系统采用ARM7S3C44BOX芯片控制EPSON公司M一150II型打印机芯实现了微型打印功能。     

Cyclic behavior of full-scale reinforced high-strength recycled aggregate concrete columns

In order to expand the application of high-strength recycled concrete, five full-scale square high-strength recycled concrete columns (600 × 600 mm) were tested under the experimental axial compression ratio (ACR) of 0.54. The seismic behavior of reinforced high-strength recycled aggregate concrete columns under high ACR and the effects of recycled coarse aggregate (RCA) replacement ratio and ACR on the seismic behavior were analyzed. The results showed that the high-strength recycled concrete columns have potential to collapse-resistance capacity subjected to strong earthquakes. Under the similar concrete strengths, the mechanical properties of high-strength recycled aggregate concrete columns and ordinary concrete columns were comparable even under high ACR. As the ACR increased from 0.35 to 0.54, the bearing capacity increased by up to 12.6%, while the ductility decreased by up to 32.8%. The specimens with 100% RCA were more sensitive to ACR than those with 50% RCA. A four-fold restoring force model considering the effects of axial load, reinforcement ratio, shear span, and RCA replacement ratio was established, which was in good agreement with the experimental curves.     

Nano-tin alloys dispersed in oxides for lithium storage materials

Finely dispersed tin alloy/oxide composites were synthesized via the reduction of tin oxide by aluminum under high-energy ball-milling. The morphology and crystal structure of the resulting samples were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The electrochemical measurements reveal that Sn₃Co/Al₂O₃ composite has higher initial efficiency and better cycle performance than Sn/Al₂O₃. The Sn₃Co/Al₂O₃ composite electrode containing LA132 binder exhibited a reversible capacity about 540 mA h g⁻¹ with good capacity retention. On the other hand, it is found that the influence of binder type on the electrode performance is remarkable.     

Cyanidin-3-O-β-glucoside improves obesity and triglyceride metabolism in KK-Ay mice by regulating lipoprotein lipase activity

BACKGROUND: Cyanidin‐3‐O‐β‐glucoside (Cy‐3‐g)‐rich foods have been reported to inhibit the onset of obesity, but whether the pure anthocyanin supplementation affects obesity remains uncertain. RESULTS: Cy‐3‐g supplementation significantly reduced obesity, accumulation of fat in visceral adipose and liver tissues, and plasma triglyceride levels. Furthermore, adenosine monophosphate (AMP)‐activated protein kinase phosphorylation (pAMPK) in the skeletal muscle and visceral adipose were significantly increased by Cy‐3‐g consumption. This was followed by the activation of lipoprotein lipase (LPL) in plasma and skeletal muscle but the suppression of this enzyme in visceral adipose. LPL activation in skeletal muscle cells and its suppression in adipocytes by Cy‐3‐g were blocked by inhibition of pAMPK. CONCLUSION: Our present data thus demonstrate that Cy‐3‐g improves obesity and triglyceride metabolism in KK‐Ay mice. The underlying mechanism is found to be partly related to the activation of LPL in plasma and skeletal muscle, and inhibition of LPL in adipose tissue following the activation of pAMPK. Copyright © 2011 Society of Chemical Industry     

基于1,2,4-三羧基-3-羧甲基环戊烷二酐的可溶性聚酰亚胺垂直取向剂的制备及性能

采用1,2,4-三羧基-3-羧甲基环戊烷二酐（TCA）、4,4’-二氨基二苯甲烷（MDA）及长侧链二胺4-十二烷氧基苯甲酸酯联苯酚-3’,5’-二胺基苯甲酸酯（DBPDA）共聚制备了一系列的聚酰亚胺。并对其溶解性能、透光性能及取向性能进行了测试。结果显示,聚酰亚胺在有机溶剂中可溶,成膜后紫外透光率较高,在波长400 n...     

Design for emergence: experiments with a mixed reality urban playground game

In this paper we present our work in the design of ubiquitous social experiences, aiming to foster group participation and spontaneous playful behaviours in a city environment. We outline our approach of design for emergence: to provide just enough of a game context and challenge for people to be creative, to extend and enrich the experience of play through their interaction in the real world. CitiTag is our mixed reality testbed, a wireless location-based multiplayer game based on the concept of playground ‘tag’. We describe the design and implementation of CitiTag and discuss results from two user studies.     

基于USB2.0MIT-BIH心电数据回放系统的设计

设计基于USB2.0的D/A转换模块,文中对模块的主要芯片、主要原理、接口函数及主要性能进行了介绍.通过取一心电数据通过vc编程将其进行D/A转换,输出波形与原始波形进行比较,较好的实现了回放功能.由此可见,该模块的性能指标达到了设计要求.心电数据回放很好的实现,为一系列心电算法的仿真实践及实时心电监护仪的研制打好了基础.     

A Highly Reversible Zn Anode with Intrinsically Safe Organic Electrolyte for Long‐Cycle‐Life Batteries

Dendrite and interfacial reactions have affected zinc (Zn) metal anodes for rechargeable batteries many years. Here, these obstacles are bypassed via adopting an intrinsically safe trimethyl phosphate (TMP)‐based electrolyte to build a stable Zn anode. Along with cycling, pristine Zn foil is gradually converted to a graphene‐analogous deposit via TMP surfactant and a Zn phosphate molecular template. This novel Zn anode morphology ensures long‐term reversible plating/stripping performance over 5000 h, a rate capability of 5 mA cm^?2, and a remarkably high Coulombic efficiency (CE) of ≈99.57% without dendrite formation. As a proof‐of‐concept, a Zn–VS₂ full cell demonstrates an ultralong lifespan, which provides an alternative for electrochemical energy storage devices.     

基于残差梯度法的神经网络Q学习算法

针对连续状态空间的非线性系统控制问题,提出一种基于残差梯度法的神经网络Q学习算法。该算法采用多层前馈神经网络逼近Q值函数,同时利用残差梯度法更新神经网络参数以保证收敛性。引入经验回放机制实现神经网络参数的小批量梯度更新,有效减少迭代次数,加快学习速度。为了进一步提高训练过程的稳定性,引入动量优化。此外,采用Softplus函数代替一般的ReLU激活函数,避免了ReLU函数在负数区域值恒为零所导致的某些神经元可能永远无法被激活,相应的权重参数可能永远无法被更新的问题。通过CartPole控制任务的仿真实验,验证了所提算法的正确性和有效性。