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301.
林火定位是林火智能监测设备的核心技术。提出了一种基于激光雷达、红外热像仪及组合惯导多数据融合的火点定位方法。首先设计了一个通用的无人机吊舱系统,并基于ROS框架实现数据采集、数据处理和数据传输等功能;其次提出了一个基于无人机吊舱系统的火点全局定位方案,根据红外热像仪成像特性识别火点,同时将密集点云与红外图像进行数据融合,估计出火点的三维空间位置;然后根据无人机位姿提出了一种基于墨卡托投影的火点全局定位方案,得到了火点的GPS位置。最后通过试验得到了该方案的全局定位精度:在实验中经度最大误差为2.36×10-5°,纬度最大误差为1.84×10-5°,高程最大误差为0.926 1 m,为其他林火定位方案提供了技术支持。  相似文献   
302.
The regional observatory Kosetice is a central European background station. Unique continuous monitoring from 1988 on is held here. POP (persistent organic pollutant) concentration values of air samples from Kosetice taken between 1996 and 2005 were statistically processed. Values of Czech ambient air quality standards were not exceeded. Concentrations of polycyclic aromatic hydrocarbons reached two maxima, in 1996 and 2001-2002. Polychlorinated biphenyls concentrations reached the highest values in 1997 and 1998 and hexachlorocyclohexanes concentrations in 1998. DDTs, hexachlorobenzene and pentachlorobenzene were analysed as well. Long-range transport of pollutants between 2002 and 2005 was evaluated using the Potential Source Contribution Function hybrid receptor model. Indicated potential source areas of PCBs coincide with many well-known urban and industrialised areas, while the indicated potential source areas of HCHs and DDTs coincide with many agricultural and/or forested regions and the potential source areas of HCB comprise all land use types.  相似文献   
303.
GOAL, SCOPE, AND BACKGROUND: Diesel exhaust is believed to consist of thousands of organic constituents and is a major cause of urban pollution. We recently reported that a systematic separation procedure involving successive solvent extractions, followed by repeated column chromatography, resulted in the isolation of vasodilatory active nitrophenols. These findings indicated that the estimation of the amount of nitrophenols in the environment is important to evaluate their effect on human health. The isolation procedure, however, involved successive solvent extractions followed by tedious, repeated chromatography, resulting in poor fractionation and in a significant loss of accuracy and reliability. Therefore, it was crucial to develop an alternative, efficient, and reliable analytical method. Here, we describe a facile and efficient acid-base extraction procedure for the analysis of nitrophenols. MATERIALS AND METHODS: Diesel exhaust particles (DEP) were collected from the exhaust of a 4JB1-type engine (ISUZU Automobile Co., Tokyo, Japan). Gas chromatography-mass spectrometry (GC-MS) analysis was performed with a GCMS-QP2010 instrument (Shimadzu, Kyoto, Japan). RESULTS: A solution of DEP in 1-butanol was extracted with aqueous NaOH to afford a nitrophenol-rich oily extract. The resulting oil was methylated with trimethylsilyldiazomethane and subsequently subjected to GC-MS analysis, revealing that 4-nitrophenol, 3-methyl-4-nitrophenol, 2-methyl-4-nitrophenol, and 4-nitro-3-phenylphenol were present in significantly higher concentrations than those reported previously. DISCUSSION: Simple acid-base extraction followed by the direct analysis of the resulting extract by GC-MS gave only broad peaks of nitrophenols with a poor detection limit, while the GC-MS analysis of the sample pretreated with (trimethylsilyl)diazomethane gave satisfactorily clear chromatograms with sharp peaks and with a significantly lowered detection limit (0.5 ng/ml, approximately 100 times). CONCLUSION: The present method involving an acid-base extraction, in situ derivatization, and GC-MS analysis has shown to be a simple, efficient, and reliable method for the isolation and identification of the chemical substances in DEP.  相似文献   
304.
碱熔融法合成NaA和NaX型粉煤灰沸石的品质表征   总被引:10,自引:2,他引:8  
以粉煤灰为原料采用碱熔融法合成了2种单一沸石矿物种的NaA和NaX型沸石,并对产物的结构、性能和应用指标进行了详细表征.经x射线衍射和IR光谱分析,表明合成产物是无杂晶生成的NaA和NaX型沸石相;在扫描电镜观察下,产物分别具有NaA和NaX型沸石的立方体和八面体晶体骨架结构.DTA分析表明了合成产物中沸石水的存在,且产物热稳定性较好.通过对比,粉煤灰合成的NaA和NaX型沸石的比表面积达到了相应商品沸石的66.9%和83.6%;孔容为41.1%和70.2%;阳离子交换容量(CEC,cation exchange capacity)为82.93%和84.31%.通过比较化学组成表明,大规模应用合成产物不会对环境造成危害.  相似文献   
305.
环境保护是科学发展观的题中之意,科学发展观关于环境保护的论述,是党的环境保护理论的精髓。学习实践科学发展观活动,是一个哲学内涵非常丰富的课题,是十分难得的研究环境哲学的大好机遇。试点经验显示了环境保护在学习实践科学发展观活动中的重要作用。他们一方面在科学发展中通过转变发展方式,调整经济结构,解决环境难题;一方面坚持环境保护与经济发展并重,在保护环境中求发展,努力实现环境与经济“双赢”。其共性是,注重治本、注重生态、注重政策。深入学习实践科学发展观,关键在实践,要深入一线,深入调研,融人群众的实践,总结来自一线的新鲜经验。要适应新形势,了解新情况,解决新问题。在学习实践科学发展观活动中,不断提高落实科学发展观,在科学发展中,提高解决环境问题的能力,实现环境与发展、环境与经济的“双赢”。  相似文献   
306.
A new and simple equation has been presented here for calculation of adsorption and desorption rate constants of Langmuir-Freundlich kinetic equation. The derivation of new equation is on the basis of extension and correction to the geometric method which has been presented by Kuan et al. [Kuan, W.-H., Lo, S.-L., Chang, C.M., Wang, M.K., 2000. A geometric approach to determine adsorption and desorption kinetic constants. Chemosphere 41, 1741-1747] for the kinetics of adsorption/desorption in aqueous solutions. The correction is to consider that the concentration of solute is not constant and changes as adsorption proceeds. The extension is that we applied Langmuir-Freundlich kinetic model instead of Langmuir kinetic model to consider the heterogeneity and therefore it is more applicable to the real systems. For solving Langmuir-Freundlich kinetic model, some geometric methods and also Taylor expansion were used and finally a simple and novel equation was derived (Eq. (20)) for calculation of adsorption rate constant. This new method was named "extended geometric method". The input data of the obtained equation can be simply derived from initial data of adsorption kinetics. Finally the adsorption of methyl orange onto granular activated carbon was carried out at dynamic and equilibrium conditions and the capabilities of extended geometric method were examined by the experimental data.  相似文献   
307.
双碱法脱硫技术研究   总被引:3,自引:0,他引:3  
脱硫过程主要是二氧经硫与氢氧化钠生发化学反应,反应生成物亚硫酸钠溶于水,含亚硫酸钠的脱硫循环水与投加的氢氧化钙反应可生成氢氧化钠和亚硫酸钙。通过沉淀分离可将难溶钙从循环水中清除,氢氧化钠易溶于水可循环使用,脱硫过程中消耗氢氧化钙。达到脱硫效率高,运行费用低的目的。  相似文献   
308.
从顽拗植物荔枝中提取基因组DNA技术的研究   总被引:35,自引:0,他引:35  
针对荔枝体内含有大量影响DNA提取质量的多酚等次生代谢物质的特点,在常规SDS和CTAB提取方法的基础上做了技术改进,即在核裂解之间先破碎细胞,将存在于细胞质中次生物质除去后再裂解细胞核,同时加入活性炭以吸咐杂质反复清洗几次后加入核型解液释放基因组DNA,纯化之后经外观和电泳检测,以及D260nm和D280nm比值的测定,限制性内切酶反应,PCR扩增的结果表明,用改进方法提取的DNA无论在纯度上还  相似文献   
309.
The use of quantitative data for constructing prognostic maps of the dynamics of ecosystem degradation and restoration by nonlinear simulation methods is a topical field of landscape ecology. This method of dynamic cartography is based on fiberwise comparison of data on the state of Chernye Zemli (the Kalmyk Republic, Russia) in different years and the detailed analysis of the period on which the prognosis was based. For this purpose, materials of repeated aerial and satellite photography obtained during a long period (1954–1993) were used. Comparison of maps characterizing the dynamics of Chernye Zemli between 1958 and 1993 allows prognostic electronic maps for the next 10–15 years (with a five-year interval) to be drawn and land prognosis for the next 20–30 years (1998–2023) to be obtained. Deceased  相似文献   
310.
介绍了采用称量法制备瓶装1μmol/mol氮气中42个组分挥发性有机物(VOCs)标准物质的研制方法。建立了选择离子模式,气相色谱-质谱联用的分析方法,对目标组分在气瓶中的长期稳定性进行了考察。所选择的42种目标组分完全满足中国环境保护标准《环境空气挥发性有机物的测定吸附管采样-热脱附/气相色谱-质谱法》(HJ 644—2013)和美国环保署《使用特殊处理的采样罐/气相色谱仪检测环境大气中的挥发性有机物》(EPA TO—14A)这2个方法标准中所规定的环境空气中挥发性有机有害成分的监测要求。将研制的气体标准物质与中国计量科学研究院(NIM)和英国国家物理实验室(NPL)分别进行了比对测试,取得了良好的比对结果与国际等效度。结果表明,1μmol/mol氮气中42种组分VOCs标准物质的有效期为一年,相对扩展不确定度为5.0%(包含因子k=2),并取得国家标准物质证书GBW(E)062231。  相似文献   
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