共查询到20条相似文献，搜索用时 281 毫秒
1.
室内材料包括建筑、装饰和装修材料,这些材料在整个生命周期都能释放挥发性有机化合物(VOCs),是室内VOCs的主要释放源.VOCs存于室内环境中可对人体健康造成危害.从挥发性有机物VOCs的来源、危害等方面对室内环境污染进行阐述,并提出有效的防治措施,以降低和减少VOCs的危害. 相似文献
2.
Qing-yu ZHANG Xin-xing LI Wei-li TIAN Ang-yi FU Wei-fei DU Cui WANG 《浙江大学学报(A卷英文版)》2014,15(9):753-760
研究目的：预测机动车保有量;根据机动车污染特征,预测机动车污染物排放量;评估不同管理措施下机动车污染物的削减效果。创新要点：综合不同管理措施,整合评价多种管理措施并行条件下,机动车污染物排放量的削减情况。研究方法：通过长期能源替代计划（LEAP）模型对机动车保有量进行预测,相关排放因子采用校正的能源替代（AER）模型进行估算。最后设计四个情景模式,评估不同情景的减排效果,并与基础情景进行对比。重要结论：1.至2015年杭州市机动车将增长60.7%。2.淘汰超标机动车和提高机动车污染排放标准能有效控制CO和VOCs,而对NOx和PM的总量削减效果不明显。3.采用多种控制手段,如淘汰劣化超标机动车、提高机动车排放标准、提供低硫代燃油及引进能源替换型机动车将大大减少机动车污染物的排放量。 相似文献
3.
Development of an evaporation crystallizer for desalination of alkaline organic wastewater before incineration 总被引：2，自引：0，他引：2
A wastewater evaporation-desalination pretreatment method was introduced to remove the Na^＋ and K^＋ salts in volatile organic compounds （VOCs） wastewater before it was fed into the incinerator. VOCs in the wastewater were volatilized in the evaporation system and then the vapor was combusted in an incinerator. Simulated phenol wastewater containing sodium chloride was evaporated and concentrated and sodium chloride was crystallized in different parameters. The experimental results showed that the higher initial concentration of sodium chloride increases the ratio of volatilization of VOCs, which was due to the effect of “salting out” （a decrease in the solubility of the nonelectrolyte in the solution, or more rigorously, an increase in its activity coefficient, caused by the salt addition （Furter and Cook, 1967））. When evaporation speed was increased from 1.67 ml/min to 2.73 ml/min, the total removal coefficient of sodium chloride was about 99.88%-99.99%. This pretreatment procedure eliminates the slag phenomenon caused by Na^＋ and K^＋ salts during wastewater incineration, so the incinerator could operate continuously, and the wastewater evaporation could increase the heat value of wastewater, and the operation cost would be reduced. 相似文献
4.
挥发性有机物(VOCs)的污染与控制技术日益受到重视。近年来发展起来的非平衡等离子体技术在治理VOCs方面已初步显示其独特的技术优势,现已成为废气治理研究领域中的前沿热点课题之一。等离子体法降解VOCs的机理较为复杂,研究不同线路对VOCs降解过程的影响意义重大。采用脉冲电晕放电等离子体技术,建立了混合电晕、有机电晕、空气电晕和分别电晕4种不同的实验方案,选取苯为代表物质进行实验研究,在初始浓度、停留时间和电源参数等一定的条件下,考察脉冲电压对苯去除率的影响。结果表明,电压为140kV、混合电晕时苯的去除率达到82.73%,脉冲电晕技术处理低浓度有机废气效果较好。 相似文献
5.
以Z-元件构成智能传感器,利用了Z-型传感器输出幅度大而且可以输出频率量的独特优点,省去了A/D转换器等硬件电路,使得电路结构简单、焊点少、可靠性高、成本低廉。针对Z-元件存在的缺点,通过软件编程克服了Z-型传感器存在的非线性、分散性等缺陷。将Z-元件敏感元件与微型单片机融为一体,构成体积小、成本低、输出标准数字量的传感器。该方法可用于实际应用领域,经过实测,Z-元件构成的数字传感器输出满足一般精度的要求。 相似文献
6.
Volatile organic compounds （VOCs） emitted from three types of carpets used in aircrafts were compared by using headspace and dynamic chamber tests. The headspace samples contained many compounds that were not detected in the dynamic chamber test;in addition, the dominant VOCs found by these two methods were different. The findings indicate that for highly sorptive materials such as carpets, headspace analysis may give inaccurate indication of actual VOC emissions, and it is necessary to conduct dynamic chamber tests over a certain period of time in order to identify the true emission characteristics. From the dynamic chamber tests, 2-ethyl-1-hexanol was the main VOC emitted from all three carpets. The study also examined the emission characteristics of aircraft carpets. In all experiments, total VOC （TVOC） concentration peaked within a few hours after the start of the experiment and was followed by rapid decay. The emission parameters of TVOC emitted by all three carpets were calculated and the simulated data matched the measured data well. 相似文献
7.
李华 《商洛师范专科学校学报》2014,(4):27-31
为了满足实际项目需求,设计了一套基于FPGA结合CMOS图像探测器的轻小型彩色数字相机系统。根据项目特点,选用了一片Xilinx公司FPGA作为硬件设计平台．使用Verilog—HDL硬件描述语言并采用自上而下的模块化设计对整个系统进行硬件描述．对图像探测器时序驱动、输出图像格式重组、彩色图像恢复等功能进行了详细的设计。试验结果表明,所设计的图像采集系统在1280＊1024模式、25f·s^-1的情况下可以实时稳定的实现彩色图像的显示与存储。 相似文献
8.
Based on the characteristic curve analysis, the method using Δ(K 2) square difference of meter factor at different flow rates was developed to evaluate the performance of turbine flow sensor in this study. Then according to the distribution of entrance velocity, it was supposed that reducing the blade area near the tip could decrease the linearity error of a sensor. Therefore, the influence of different blade shape parameters on the performance of the sensor was investigated by combining computational fluid dynamics(CFD)simulation with experimental test. The experimental results showed that, for the liquid turbine flow sensor with a diameter of 10 mm, the linearity error was smallest, and the performance of sensor was optimal when blade shape parameter equaled 0.25. 相似文献
9.
利用吹扫捕集-GC/MS方法检测地下水中挥发性有机物,并优化了吹扫捕集条件和二级质谱条件.各组分的线性方程相关系数均在0.999 1以上,方法检出限为0.1～0.4μg/L,相对标准偏差为1.6%～6.9%（n=7）,加标回收率为84.9%～101%.建立的方法检出限低,精密度好,干扰少,便捷,适合于大批量地下水中挥发性有机物的检测. 相似文献
10.
提出了一种基于Volterra系数模型, 用于提高非线性传感器性能的新方法. Volterra模型可作为一个非线性滤波器用于降低传感器的噪声, 并可对传感器进行非线性补偿. 在实验中, 采用精度较低的压力传感器MPX10作为实验传感器, 采用具有较高精度的传感器MPX2010产生构建Volterra模型的训练学习数据. 仿真实验表明, 利用Volterra 模型进行滤波, 传感器MPX10的精度由原来的0. 354～0. 42 变为 0. 041～0. 053. 由此可见该方法可有效地提高传感器的性能与精度, 并具有较高的环境适应能力. 相似文献
11.
为了通过CMOS图像探测器实时准确的获取图像,设计了一套基于FPGA结合SDRAM的实时图像采集系统。根据CMOS图像探测器输出图像格式的特点,选用了一片Xilinx公司FPGA作为硬件设计平台,使用Verilog-HDL硬件描述语言并采用自上而下的模块化设计对整个系统进行硬件描述,对输出图像格式重组、图像信息添加等功能进行了详细的设计。试验结果表明,所设计的图像采集系统在全帧模式、20 f·s-1的情况下可以实时稳定的实现图像的显示与存储,而且具有较好的通用性。 相似文献
12.
基于无线传感器网络的单目标跟踪系统设计 总被引：1，自引：1，他引：0
介绍了短距离、低速率无线网络技术ZigBee,并对其网络拓扑结构进行分析,对基于无线传感器网络的目标跟踪技术进行讨论,利用JN5121芯片设计无线传感器自组织网络实现对单个运动目标的跟踪．试验结果表明设计的网络能够满足单个运动目标的跟踪． 相似文献
13.
赵辉映 《湖南师范大学教育科学学报》1996,(2)
根据热力学原理，单组分体系中，物质饱和蒸气压的对数与相应的温度的倒数成直线关系。本文编写了用最小二乘法处理单组分体系中物质饱和蒸气压—温度关系的ＢＡＳＩＣ程序． 相似文献
14.
Amit R Morarka 《Resonance》2018,23(11):1259-1272
The article demonstrates the condensation of water vapour under pressure and at room temperature, using a disposable syringe and an ambient light source. The small amount of trapped water vapour inside a syringe along with the air is compressed manually to one-sixth of its original volume. The compressed water vapour inside the syringe can be easily seen in the form of a white condensate on the inner side of the transparent, circular wall of the syringe. The condensate cloud can be observed in the atmosphere by releasing it in the open air while holding the syringe in front of a light source over a dark background. This model can be used as an analogous experiment while explaining the concept of condensation of gases under pressure–from school to postgraduate students. 相似文献
15.
Emissions of volatile organic compounds and carbonyl compounds from residential coal combustion in China 总被引：1，自引：0，他引：1
Emissions of volatile organic compounds （VOCs） and carbonyls from residential coal combustion of five coals with different maturities were studied in a simulated room.The coals were burned in form of honeycomb briquettes in a domestic coal stove,one of the most common fuel/stove combinations in China.Through a dilution system,VOCs and carbonyls samples were collected by canisters and silica-gel cartridges and analyzed by gas chromatography and mass spectrum （GC/MS） and high performance liquid chromatography/ultraviolet （HPLC/UV）,respectively.The results show that the bituminous coals with medium volatile matter content produce the highest emissions while the anthracite yields the lowest.Among the identified carbonyls from the coal smoke,the aromatic compounds （benzaldehyde,2,5-dimethylbenzaldehyde and p-tolualdehyde,m/o-tolualdehyde,benzene,m,p-xylene and trimethyl-benzene） were relatively abundant,which might be due to the molecular structure of the coal.For formaldehyde,aromatic carbonyls and aliphatic alkanes,their concentrations increase up to the maximum values and then decrease with increasing coal maturity.The total carbonyls and VOCs have the same tendency,which was observed for the emission factors of organic carbon （OC）,elemental carbon （EC）,particulate matter （PM） and polycyclic aromatic hydrocarbons （PAHs） detected in the series study. 相似文献
16.
变气隙自感传感器是传统检测技术中一种常用的典型传感器,然而对其分析中经常出现近似简化错误。这与该传感器实验性知识缺失有关。作者介绍了一个在变气隙自感传感器分析中应用MATLAB模拟辅助实验的实例,并指出了通常对该传感器近似简化分时的概念性错误。 相似文献
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18.
With the development of industrialization, the emission of volatile organic compounds (VOCs) to atmosphere causes serious environmental problems and the treatme... 相似文献
19.
赵元苏 《北京工业职业技术学院学报》2011,10(3):36-39
为了让机器可以代替人类在危险地带工作,介绍了一种基于ARM9芯片（S3C2440）,使用传感器、USB摄像头、无线网卡等外设,搭建出可被遥控的、能将采集到的视频数据通过无线网络传回的移动平台。嵌入式操作系统采用Linux,应用程序编程语言使用C语言。 相似文献
20.
With the mandate of Montreal Protocol banning ozone depleting substances, and Kyoto Protocol later on curtailing the use of
substances which contribute to global warming, conventional refrigerants are to be replaced by environment-friendly working
fluids. Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are being substituted by hydrofluorocarbons (HFCs),
hydrofluorooelifins (HFOs), and a variety of mixtures. In view of the global warming potential of these newly synthesized
refrigerants, the recent trend is to go back to the originally used natural fluids such as ammonia, carbon dioxide, hydrocarbons,
water vapour, etc. In this article, various issues related to this changeover of refrigerants being used in vapour compression
refrigeration systems are discussed. 相似文献