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1.
Environmental Science and Pollution Research - At present, the contradiction between survival and ecology necessitates the integration of crop planting, chemical fertilizer application, and...  相似文献   
2.
Environmental Science and Pollution Research - Hydrothermal liquefaction (HTL) of biomass used HTL reaction under high temperature and pressure to produce bio-oil. This technology is considered as...  相似文献   
3.
为了解全氟辛烷磺酸盐(perfluorooctane sulfonate, PFOS)暴露对半滑舌鳎(Cynoglossus semilaevis)免疫功能的影响,在实验室条件下,运用RT-PCR方法分析了PFOS暴露对半滑舌鳎热休克蛋白hsp70、hsp90、C型凝集素(c-type lectin)和细胞色素c氧化酶(cytochrome c oxidase, cox)等4种免疫相关基因表达水平的影响。实验测定了上述4种基因在半滑舌鳎肝、鳃、肠及肌肉4种不同组织中随时间(0、24 h、48 h、96 h和7 d)的表达变化情况。结果表明,在4种组织中,hsp70基因的表达与对照相比为上调,其中,肝组织hsp70基因的表达量显著高于其他各组织,且表达高峰值的出现也早于其他各组织;hsp90基因在肝和鳃组织中表达量随时间不同而波动,在肠组织中表达上调,在肌肉中表达显著下调;c-type lectin基因表达量与对照组相比表达显著下调或无明显差异;cox基因在肝组织和肠组织中表达下调,在鳃和肌肉中表达上调。上述研究结果表明,PFOS能引起免疫相关基因的表达变化,对半滑舌鳎具有潜在的免疫毒性。肝组织中各免疫基因对PFOS胁迫的响应高于其他组织。本研究可为阐明全氟辛烷磺酸盐对半滑舌鳎的免疫毒性提供基础数据。  相似文献   
4.
Emissions of nitrogen oxides (NOx) by vehicles in real driving environments are only partially understood. This has been brought to the attention of the world with recent revelations of the cheating of the type of approval tests exposed in the dieselgate scandal. Remote-sensing devices offer investigators an opportunity to directly measure in situ real driving emissions of tens of thousands of vehicles. Remote-sensing NO2 measurements are not as widely available as would be desirable. The aim of this study is to improve the ability of investigators to estimate the NO2 emissions and to improve the confidence of the total NOx results calculated from standard remote-sensing device (RSD) measurements. The accuracy of the RSD speed and acceleration module was also validated using state-of-the-art onboard global positioning system (GPS) tracking. Two RSDs used in roadside vehicle emissions surveys were tested side by side under off-carriageway conditions away from transient pollution sources to ascertain the consistency of their measurements. The speed correlation was consistent across the range of measurements at 95% confidence and the acceleration correlation was consistent at 95% confidence intervals for all but the most extreme acceleration cases. VSP was consistent at 95% confidence across all measurements except for those at VSP ≥ 15 kW t?1, which show a small underestimate. The controlled distribution gas nitric oxide measurements follow a normal distribution with 2σ equal to 18.9% of the mean, compared to 15% observed during factory calibration indicative of additional error introduced into the system. Systematic errors of +84 ppm were observed but within the tolerance of the control gas. Interinstrument correlation was performed, with the relationship between the FEAT and the RSD4600 being linear with a gradient of 0.93 and an R2 of 0.85, indicating good correlation. A new method to calculate NOx emissions using fractional NO2 combined with NO measurements made by the RSD4600 was constructed, validated, and shown to be more accurate than previous methods.

Implications: Synchronized remote-sensing measurements of NO were taken using two different remote-sensing devices in an off-road study. It was found that the measurements taken by both instruments were well correlated. Fractional NO2 measurements from a prior study, measurable on only one device, were used to create new NOx emission factors for the device that could not be measured by the second device. These estimates were validated against direct measurement of total NOx emission factors and shown to be an improvement on previous methodologies. Validation of vehicle-specific power was performed with good correlation observed.  相似文献   
5.
本文从医学测试、体质测试和心理测试三个方面论述了消防员职业健康测试项目研究的重要性,以促进我国消防员职业健康研究水平的提高。  相似文献   
6.
Fu  Li  Chen  Yi  Yang  Xinyi  Yang  Zuyao  Liu  Sha  Pei  Lei  Feng  Baixiang  Cao  Ganxiang  Liu  Xin  Lin  Hualiang  Li  Xing  Ye  Yufeng  Zhang  Bo  Sun  Jiufeng  Xu  Xiaojun  Liu  Tao  Ma  Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...  相似文献   
7.
Environmental Science and Pollution Research - Anaerobic batch experiments were conducted to study the regulatory role of endogenous iron in greenhouse gas emissions under intensive nitrogen...  相似文献   
8.
以丝瓜络为原料,采用醚化-接枝技术制备出季胺基阴离子交换吸附剂。采用电镜扫描、傅里叶红外光谱、比表面积孔径分布测定仪和元素分析仪等仪器对其进行分析和结构表征,并考察了温度、p H和硝酸盐初始浓度等因素对NO-3去除率的影响。实验结果表明,在20℃,p H值为3~10时,NO-3的吸附率可达90%左右;在不同温度下该吸附过程用Langmuir等温线模型和Freundich等温线模型描述均可;与伪一级动力学方程相比,伪二级动力学方程能更好地描述其吸附动力学方程。  相似文献   
9.
Current wastewater treatment technologies do not remove many unregulated hydrophilic compounds, and there is growing interest that low levels of these compounds, referred to as emerging contaminants, may impact human health and the environment. A probabilistic-designed monitoring network was employed to infer the extent of Florida’s ambient freshwaters containing the wastewater (Includes reuse water, septic systems leachate, and wastewater treatment effluent.) indicators sucralose, acetaminophen, carbamazepine, and primidone and those containing the widely used pesticide imidacloprid. Extent estimates with 95% confidence bounds are provided for canals, rivers, streams, small and large lakes, and unconfined aquifers containing ultra-trace concentrations of these compounds as based on analyses of 2015 sample surveys utilizing 528 sites. Sucralose is estimated to occur in greater than 50% of the canal, river, stream, and large lake resource extents. The pharmaceuticals acetaminophen, carbamazepine, and primidone are most prevalent in rivers, with approximately 30% of river kilometers estimated to contain at least one of these compounds. Imidacloprid is estimated to occur in 50% or greater of the canal and river resource extents, and it is the only compound found to exceed published toxicity or environmental effects standards. Geospatial analyses show sucralose detection frequencies within Florida’s drainage basins to be significantly related to the percentage of urban land use (R2?=?0.36, p?<?0.001), and imidacloprid detection frequencies to be significantly related to the percentage of urban and agricultural land use (R2?=?0.47, p?<?0.001). The extent of the presence of these compounds highlights the need for additional emerging contaminant studies especially those examining effects on aquatic biota.  相似文献   
10.
Personal aerosol samplers are widely used to monitor human exposure to airborne materials. For bioaerosols, interest is growing in analyzing samples using molecular and immunological techniques. This paper presents a personal sampler that uses a two-stage cyclone to collect bioaerosols into disposable 1.5 ml Eppendorf-type microcentrifuge tubes. Samples can be processed in the tubes for polymerase chain reaction (PCR) or immunoassays, and the use of multiple stages fractionates aerosol particles by aerodynamic diameter. The sampler was tested using fluorescent microspheres and aerosolized fungal spores. The sampler had first and second stage cut-off diameters of 2.6 microm and 1.6 microm at 2 l min(-1)(geometric standard deviation, GSD = 1.45 and 1.75), and 1.8 microm and 1 microm at 3.5 l min(-1)(GSD = 1.42 and 1.55). The sampler aspiration efficiency was >or=98% at both flow rates for particles with aerodynamic diameters of 3.1 microm or less. For 6.2 microm particles, the aspiration efficiency was 89% at 2 l min(-1) and 96% at 3.5 l min(-1). At 3.5 l min(-1), the sampler collected 92% of aerosolized Aspergillus versicolor and Penicillium chrysogenum spores inside the two microcentrifuge tubes, with less than 0.4% of the spores collecting on the back-up filter. The design and techniques given here are suitable for personal bioaerosol sampling, and could also be adapted to design larger aerosol samplers for longer-term atmospheric and indoor air quality sampling.  相似文献   
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