单通道TD-SCDMA射频拉远单元

该文设计了一种单通道TD-SCDMA射频拉远单元。首先根据系统要达到的性能指标要求,设计了系统拓扑结构,接着从该系统拓扑结构出发,分析了整个系统的设计思路及实现方案,选择相应的电路模块。测试结果表明设计的系统达到了预期的指标,临近通道功率比小于-40.64 dBc和误差向量幅度为5.08%rms。     

对安徽省城镇体育人口与经济发展特征探析

运用文献资料、访谈、问卷调查、数理统计等研究方法,对安徽省城镇体育人口现状进行调查研究,结果显示:安徽省经济发展迅速,社会体育人口比率与城镇居民人均可支配收入成正比,与各地市人口总数成反比。安徽省城镇体育人口性别比为109.55,分别高出全国和安徽省人口性别比4.35和6.16。     

乳胶漆对比率的影响因素

讨论了影响乳胶漆对比率的各种因素。     

Light composite elliptic springs for vehicle suspension

For composites to compete in vehicle suspension applications, it is essential to control their failure by utilising their strength in principal direction instead of shear. This can be achieved efficiently by employing a new configuration instead of existing one. This study marries between an elliptical configuration and the woven roving composites.

In this paper, the influence of ellipticity ratio on performance of woven roving wrapped composite elliptical springs has been investigated both experimentally and numerically. A series of experiments was conducted for composite elliptical springs with ellipticity ratios (a/b) ranging from one to two. Typical failure histories of their failure mechanism are presented and discussed. In general, this study demonstrated that composites elliptical spring can be used for light and heavy trucks and meet the requirements, together with substantial weight saving. The results showed that the ellipticity ratio significantly influenced the spring rate and failure loads. Composite elliptic spring with ellipticity ratios of a/b 2.0 displayed the highest spring rate.     

A coaxial pulsed plasma thruster using chemical propellants

Pulsed plasma thrusters (PPTs) have the advantages of mechanical simplicity and robustness compared to other electric propulsion systems. However the thrust power ratio of PPTs is lower than that of other electric propulsion systems. To enhance the thrust performance of the PPT, we propose to use several combustible solid chemicals as coaxial PPT propellants to replace Teflon^® (Polytetrafluoroethylene: PTFE). With the design, the force obtained thermodynamically is expected to augment the PPT thrust power ratio with the help of the chemical energy contained in the propellants. As a result, the thrust power ratio is increased using hydroxyl-terminated polybutadiene-ammonium perchlorate (HTPB-AP)-based propellants compared to the case of ordinary Teflon. The discharge current and voltage waveform does not change even when the propellant is changed. These findings could indicate that the impulse bits by gasdynamic contribution are lager in the case of chemical solid propellants than in the case of Teflon.     

Relationship Among Reserve Ratio, Government Spending and Economic Growth

The relationship among reserve ration, government spending and economic growth was analyzed. A monetary endogenous growth model is well developed by taking into account the growth-enhancing effects of reserve-augmenting seigniorage. If the government spends all the seigniorage revenue on the provision of a public input which has positive externality on the private sector‘s production, some results to be utterly different from Bronx‘s have been obtained: the economy has a unique saddle-balanced growth path, but it has nothing to do with reserve ratio. However, the higher reserve ratio, the faster speed of economic convergence.     

Stochastic structural model of rock and soil aggregates by continuum-based discrete element method

Ancient slope[1], debris-flow deposit[2] and rock-filling dam[3] are usually made of rock and soil aggregates (RSA). The RSA is a typical inhomogeneous and discontinuous medium, and its main characteristics include: (i) loose piling up by blocks or particles, (ii) mixing of different blocks with a range of shapes and sizes, (iii) stochastic distribu- tion of blocks in space, (4) fillings often in between blocks. The mechanical properties of these rock and soil aggregates are commonly obtaine…     

用于BaF2闪烁光慢成分抑制的膜系设计及制备

利用BaF2闪烁光快、慢成分处于不同波段的性质，设计出了具有特定带隙的膜系结构，用于抑制发射光谱中的慢成分。在保证快成分具有一定透过率条件下，实现了对BaF2闪烁光慢成分的全方向抑制，使晶体的快慢比得到很大提高。从膜系γ射线辐照损伤的结果可知：辐照对膜系透射带和截止带的影响不大，辐照后的膜系仍能满足抑制要求。     

高流速双室床节水效果评价

高流速双室床(HDCB)是我国自主开发的一项水处理新技术。陕西某热电厂1年多的运行结果表明,其自用水率仅为3.2%,远低于反渗透(33%)及其他离子交换技术(10%)。HDCB自用水率低是由其结构及运行特性决定的,它具有周期制水量大,再生步骤少,再生过程用水量少,大反洗(清洗)次数少等特性,是目前化学水处理技术中节水效果最好的一种技术。