澳大利亚安防市场将跑在世界前列

澳大利亚安防市场营业额很大情况下取决于其经济状况。据美国Freedonia集团的世界安防产品及系统公司报告，澳大利亚安防市场正以每年9％的速度增长，预计2002年将达到6．1亿美元，发展速度超过其他发达国家。     

黄埔电厂6~#机组锅炉电除尘器改造

电除尘器在不改变除尘器整体尺寸、不增加电场数量、保持比集尘面积基本不变的情况下,通过改造阴阳极、振打系统,使得电除尘器的除尘效率明显提高。     

环球扫描

<正>《自然》2014年12月18日无国界生物多样性保护保护区的设立旨在减轻人为因素对生物多样性造成的压力。一个国际认同的目标是,到2020年,将保护区网络扩大到覆盖世界陆地面积的17%。但生物多样性在不同国家和不同生境之间是不均匀分布的,这便提出了应当对哪些区域予以保护、以产生最大效果的问题。Federico Montesino Pouzols等人发现,通过国际协调行动将保护区网络扩大到17%这个目标,     

改进的LMS算法在Simulink仿真平台实现

目的将改进的变步长LMS算法在Simulink平台上实现。方法对LMS算法进行基础研究,详细地探究变步长算法在信号处理中的收敛速度和失调两个方面的内容,改进变步长算法,并验证算法的有效性。基于S-fuction,对改进的LMS算法建模,通过算法模块调用改进算法程序,达到对信号滤波的目的。结果仿真结果表明,算法模块能够实现算法滤波功能,能有效地抵消干扰。结论算法应用于Simulink建模,算法模块能够适应不同的Simulink平台,提高了对算法的开发与应用的效率。     

热通道结构参数对双层玻璃幕墙热工性能的影响研究

对北京某大厦的外呼吸式双层玻璃幕墙采用CFD模拟的方法,建立了矩形三维模型及设立边界条件,对热通道内的温度场和速度场进行模拟分析。通过改变热通道宽度、进出风口风速、进出风口高度等因素,分析其对双层玻璃幕墙系统热工性能的影响。得出最佳的通风方式和设计尺寸,对玻璃幕墙的结构形式和通风方式进行优化,以减少玻璃幕墙的建筑能耗。     

Synthesis of novel CeO2-BiVO4/FAC composites with enhanced visible-light photocatalytic properties

To utilize visible light more effectively in photocatalytic reactions, a fly ash cenosphere （FAC）-supported CeO2-BiV04 （CeO2-BiVO4/FAC） composite photocatalyst was prepared by modified metalorganic decomposition and impregnation methods. The physical and photophysical properties of the composite have been characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM） and energy dispersive X-ray spectroscopy （EDX）, X-ray photoelectron spectroscopy （XPS）, and UV-Visible diffuse reflectance spectra. The XRD patterns exhibited characteristic diffraction peaks of both BiVO4 and Ce02 crystalline phases. The XPS results showed that Ce was present as both Ce4＋ and Ce3＋ oxidation states in Ce02 and dispersed on the surface of BiV04 to constitute a p-n heterojunction composite. The absorption threshold of the CeO2-BiVO4/FAC composite shifted to a longer wavelength in the UV-Vis absorption spectrum compared to the pure Ce02 and pure BiV04. The composites exhibited enhanced photocatalytic activity for Methylene Blue （MB） degradation under visible light irradiation. It was found that the 7.5 wt.% CeO2-BiVO4/FAC composite showed the highest photocatalytic activity for MB dye wastewater treatment.     

环球扫描

<正>《时代周刊》2014年06月23日美国宇航局开发了一种新的太空探测器用于外太空的水下探测,该举动被称为"探索活跃的罗孚冰层(BRUIE)"。新组建的探测器能到达其他空间机器人所不能及的地方,就像木星的卫星欧罗巴一样,它可以绘制出外太空冷冻水的形态分布,同时通过粘在冰层底部的金属橡胶探头获取数据并传回实验室,从而判别该水形态下是否存在其他的生NASA新探测器瞄准外太空水下探测     

Dry deposition of PM10 over the Yellow Sea during Asian dust events from 2001 to 2007

Dry deposition velocities and fluxes of PM10during Asian dust events over the Yellow Sea from 2001 to 2007 were investigated using observation data in Qingdao, China and Jeju, Korea. The dry deposition velocities of PM10 during dust events over the Yellow Sea ranged from 0.19 to 8.17 cm/sec, with an average of 3.38 cm/sec. Dry deposition fluxes of PM10during dust events over the Yellow Sea were in the range of 68.5–2647.1 mg/(m2·day), with an average of 545.4 mg/(m2·day), which is 2–10 times higher than those reported by other studies for both dust and non-dust periods. It was estimated that 2.6 × 1011–48.7 × 1011g dust particles deposit to the Yellow Sea during dust events through dry deposition every year. Compared with the results in previous studies, it was found that the dry deposition of PM10over the Yellow Sea during dust events in the years with high frequency of dust could account for a large or overwhelming fraction of the annual total dry deposition. Backward air mass trajectory analysis showed that dust events influenced Jeju mainly originated from the desert regions located in Mongolia and Inner Mongolia, China. There were 119 backward trajectories influenced both Qingdao and Jeju during 15 dust events from 2001 to 2007, accounting for 61.3% of the total trajectories of 194, indicating that Qingdao and Jeju were usually on the same pathway of dust transport downwind from source areas.     

发挥教学睿智,让语文课堂生机勃勃

语言文字,是智慧的灵魂;语文水平高,口吐莲花,妙语连珠,人脉成串;执笔从容,临纸挥毫,文章锦绣。本文从教学方法要先进合理开始谈起,论述了多赞美少批评的意义,解读了书写速度与阅读速度的关系,最后以提问、思考促进思维发展结尾。     

风电发展不能只讲“速度”不要“质量”

风电作为国家确定的战略性新兴产业,处于成长阶段,我国风电在经过"十一五"时期的急速发展过后,较为严峻的问题集中显现.在"十二五"的开局之年,我国风电脱网事故频发、限电弃风达到了前所未有的规模、并网难尚未克服甚至更为严峻的一系列困扰风电健康发展的问题摆在我们面前.