SI engine assessment using biogas,natural gas and syngas with different content of hydrogen for application in Brazilian rice industries: Efficiency and pollutant emissions

After Asia, Brazil is the world's largest rice producer. During the processing of the grain, large amounts of husk are generated, corresponding to 22% of its weight. On the other hand, in the process of parboiling, in turn, the final result is considerable volumes of effluents rich in organic matter, generating large amounts of methane gas through anaerobic treatment. Therefore, the SI engine can operate with mixtures of biogas and syngas, generating electricity and heat in the Brazilian rice industries. In addition, it reduces the emissions of polluting gases that are generated with a direct burning of the husks instead of their gasification, as well as the use of methane gas. Accordingly, in this work, it was used the spark-ignition engine operating with one of the typical biogas and syngas compositions generated in the rice industries, named Bio65 (containing 65% of CH₄ by vol.), syngas1 (containing 18,3% of H₂ by vol.), and syngas2 (containing 13,5% of H₂ by vol.), respectively. Additionally, the tests with natural gas as a reference fuel have been performed. It was evaluated the emissions of polluting gases such as CO, NO_x and HC, as well as the thermal and electrical efficiency of all tested fuels. An important result that could be observed was that for both natural gas and biogas fuel, the increase in excess ratio (λ) value from 1 to 1.5 led to lower NO_x and CO emissions, even if with increased HC emissions. On the other hand, the Indicated Specific Energy Consumption increased to all the fuels tested in lean conditions in almost all ignition advances angles. The research tried to show that biogas and syngas can be used in parboiling rice industries, taking the advantage of the generated gases for energy self-sufficiency as well as reducing emissions.     

机顶盒解复用器适配层的设计与实现

本文提出了一套机顶盒解复用器的设计和相关的接口函数 .它具有完备 ,简单 ,通用 ,易用的特点 ,支持应用程序的各种要求 ,数目少 ,抽象程度高 ,主要描述应用程序的要求 ,并且从 MPEG和 DVB标准出发 ,不涉及解复用器操作的细节 ,可在多个硬件平台上使用 ,为应用程序提供了一个稳定的开发环境 .能够很好地支持应用程序的开发 .文中详细地介绍了它的指导思想 ,概念 ,结构 ,所提供的服务 .同时 ,还介绍了实现这些函数的关键算法 .     

半绝缘GaAs的表面光伏谱研究

利用表面光伏法（ＳＰＶ）研究了半绝缘ＧａＡｓ（ＳＩ－ＧａＡｓ）的缺陷态,通过加直流光偏置测量了室温下带边以下的光伏响应,发现带隙内缺陷态的光伏向应主要是由于表面复合而在样品表面形成协流子浓度梯度引起的,通过实验表明ＳＰＶ是一种对ＳＩ－ＧａＡｓ晶片表面质量进行检测的非常灵敏的无损检测方法。     

Multi-dimensional modelling of spray,in-cylinder air motion and fuel-air mixing in a direct-injection engine

In this work, three-dimensional fuel-air mixing inside a conventional spark ignition engine cylinder is simulated under direct injection conditions. The motivation is to explore retrofitting of conventional engines for direct injection to take advantage of low emissions and high thermal efficiency of the direct injection concept. Fuel-air mixing is studied at different loads by developing and applying a model based on the Lagrangian-drop and Eulerian-fluid (LDEF) procedure for modelling the two-phase flow. The Taylor Analogy Breakup (TAB) model for modelling the hollow cone spray and appropriate models for droplet impingement, drag and evaporation are used. Moving boundary algorithm and two-way interaction between both phases are implemented. Fuel injection timing and quantity is varied with load. Results show that near-stoichiometric fuel-air ratio region is observed at different locations depending on the load. The model developed serves to predict the fuel-air mixing spatially and temporally, and hence is a useful tool in design and optimization of direct injection engines with regards to injector and spark plug locations. Simulations over a range of speed and load indicate the need for a novel ignition strategy involving dual spark plugs and also provide guidelines in deciding spark plug locations.     

数字电视分前端系统集成的讨论

讨论地市级分前端系统构成与维护，分析不同节目源的特点及后续处理方法，结合本地节目插入对技术指标保障作具体分析，并就EPG信息的统一规划进行细致论述。     

Preparation of diamondlike carbon films using nanopulse generator employing SI thyristor

Diamondlike carbon (DLC) films show high hardness, high electric resistivity, and the self‐lubricant characteristic, and many applications and synthesis methods have been reported. Pulse plasma chemical vapor deposition (CVD) is one of the synthesis methods suitable for DLC films on complicated form work, such as molding and extruding die. Ordinary, microsecond‐order pulse is used in this method. This paper describes the development of the synthesis method using nanosecond‐order pulse plasma CVD for DLC films. To realize this process, a static induction (SI) thyristor with an inductive energy storage (IES) circuit was used. Compared with microsecond, nanosecond‐order pulse plasma CVD method shows the characteristics of high electron temperature and exponential relationship between pulse frequency and growth rate. The characteristics of the thus‐obtained DLC films show two broad peaks of the disordered band at 1360 cm^?1 and the graphitic band at 1580 cm^?1 by Raman spectroscopy and hardness of 16.0 GPa and elastic modulus of 170 GPa. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(4): 1–7, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20341     

煤岩配煤中CBI和SI指数的意义及其应用

文中阐述了ＣＢＩ和ＳＩ指标的意义和三个基本应用，并由实验方法得到计算ＣＢＩ和ＳＩ的曲线及预测焦炭强度的曲线。     

DVB-SI信息处理与机顶盒功能分析

简要分析DVB－SI各种SI信息的传同理与规范，提出了DVB－SI信息的接收策略，并进一步研究了机顶盒功能业务与相关DVB－SI信息的关系。     

业务信息私有描述符在吴江数字电视中的应用

结合吴江数字电视建设,介绍了业务信息表中插入自定义私有描述符,实现数字电视节目相关控制的可行性解决方案。     

Alternative fuel and gasoline in an SI engine: A comparative study of performance and emissions characteristics

The strict regulation of environmental laws, the price of oil and its restricted resources, has made engine manufacturers use other energy resources instead of oil and its products. Despite the fact that nowadays alternative fuels are not currently widely used in vehicular applications, using these kinds of fuels will be definitely inevitable in the future. In this paper, a computer code is developed in Matlab environment and then its results are validated with experimental data. This simulated engine model could be used as an powerful tool to investigate the performance and emission of a given SI engine fueled by alternative fuels including hydrogen, propane, methane, ethanol and methanol. Also, the superior of alternative fuels is shown by comparing the performance and emissions of alternative fueled engines to those in conventional fueled engines. Eventually, it is concluded that volumetric efficiency of the engine working on hydrogen is the lowest (28% less that gasoline fueled engine), gasoline produce more power than the all being tested alternative fuels and BSFC of methanol is 91% higher than that of gasoline while BSFC of hydrogen is 63% less than gasoline.