Measured carbon monoxide concentrations from stock and reduced-emission prototype portable generators operated in an attached garage

There is concern about the hazard of acute residential CO exposures from portable gasoline-powered generators, which can result in death or serious adverse health effects in exposed individuals. To address this hazard, the U.S. Consumer Product Safety Commission has developed low CO emission prototype generators by adapting off-the-shelf emission control technologies onto commercially available generators. A series of tests was conducted to characterize the indoor CO concentrations resulting from portable generators operating in the attached garage of a research house under seven different test house/garage configurations. The tested generators include both unmodified and modified low CO emission prototypes. It was found that CO concentrations varied widely, with peak house CO concentrations ranging from under 10 ppm to over 10,000 ppm. The highest concentrations in the house resulted from operation of the unmodified generator in the garage with the garage bay door closed and the house access door open. The lowest concentrations resulted from operation of a modified low CO emission prototype in the garage with the garage bay door open and the house access door closed. These tests documented reductions of up to 98% in CO concentrations due to emissions from two low CO emission portable generators compared to a stock generator.

Implications: Improper portable generator use has caused 800 U.S. deaths in the past 14 years. Generators operated in attached garages can cause CO to quickly reach deadly levels. Two low-emission prototypes generators were tested and had CO emissions reduced by up to 98%. Low-emission generators can reduce the risk of consumer poisonings and deaths.     

Carbon dioxide emissions from cities in China based on high resolution emission gridded data

Based on the China high resolution emission gridded data (1 km spatial resolution), this article is aimed to create a Chinese city carbon dioxide (CO₂) emission data set using consolidated data sources as well as normalized and standardized data processing methods. Standard methods were used to calculate city CO₂ emissions, including scope 1 and scope 2. Cities with higher CO₂ emissions are mostly in north, northeast, and eastern coastal areas. Cities with lower CO₂ emissions are in the western region. Cites with higher CO₂ emissions are clustered in the Jing-Jin-Ji Region (such as Beijing, Tianjin, and Tangshan), and the Yangtze River Delta region (such as Shanghai and Suzhou). The city per capita CO₂ emission is larger in the north than the south. There are obvious aggregations of cities with high per capita CO₂ emission in the north. Four cities among the top 10 per capita emissions (Erdos, Wuhai, Shizuishan, and Yinchuan) cluster in the main coal production areas of northern China. This indicates the significant impact of coal resources endowment on city industry and CO₂ emissions. The majority (77%) of cities have annual CO₂ emissions below 50 million tons. The mean annual emission, among all cities, is 37 million tons. Emissions from service-based cities, which include the smallest number of cities, are the highest. Industrial cities are the largest category and the emission distribution from these cities is close to the normal distribution. Emissions and degree of dispersion, in the other cities (excluding industrial cities and service-based cities), are in the lowest level. Per capita CO₂ emissions in these cities are generally below 20 t/person (89%) with a mean value of 11 t/person. The distribution interval of per capita CO₂ emission within industrial cities is the largest among the three city categories. This indicates greater differences among per capita CO₂ emissions of industrial cities. The distribution interval of per capita CO₂ emission of other cities is the lowest, indicating smaller differences of per capita CO₂ emissions among this city category. Three policy suggestions are proposed: first, city CO₂ emission inventory data in China should be increased, especially for prefecture level cities. Second, city responsibility for emission reduction, and partitioning the national goal should be established, using a bottom-up approach based on specific CO₂ emission levels and potential for emission reductions in each city. Third, comparative and benchmarking research on city CO₂ emissions should be conducted, and a Top Runner system of city CO₂ emission reduction should be established.     

Determinants of workers’ attitude toward low-carbon technology adoption: empirical evidence from Chinese firms

As the main contribution of China’s carbon emissions, low-carbon production in industrial firms becomes an inevitable choice, and industrial firm employees’ attitudes on low-carbon new technology directly influence the results of low-carbon production. Based on the Unified Theory of Acceptance and Use of Technology model, structural equation modeling was used to analyze the main factors influencing firm staff to accept low-carbon new technology. The study reveals that the employee’s social impact, performance expectation, effort expectations and convenient conditions, and employee characteristics are all main factors affecting their acceptance attitudes on low-carbon new technology. And social influence has the largest effect on employees’ acceptance attitudes toward low-carbon new technology. Accordingly, relevant policy recommendations are put forward for the future research direction.     

中国春季降水与南印度洋偶极子的关系研究

利用美国国家海洋和大气管理局海温资料和1951~2010年中国160站月降水量资料,分析了前期冬季（12~2月）印度洋海表温度与中国160站春季降水的关系及其影响机制。研究表明：冬季印度洋海温异常的空间模态主要有两种：符号一致的单极和东、西符号相反的南印度偶极。将第2模态的时间系数定义为南印度洋偶极子指数。该指数与中国次年春季降水关系较好,并利用NCEP/NCAR再分析资料进行机制分析,发现主要南印度洋偶极子通过以下途径影响中国春季降水：中高纬,SIOD的影响主要引起低纬度的海温及对流异常,通过中低纬度间的相互作用,在中高纬产生较强的遥响应,从而影响同期冬季欧亚大陆的环流变化,这种扰动在西风气流的作用下引起后期春季北太平洋地区对流活动异常,通过中低纬度间的相互作用,加强中高纬地区的遥响应,表现为欧亚大陆EUP波列;低纬,SIOD的影响主要引起南海-海洋性大陆的海温及对流异常,引发经向环流异常,导致黄河至长江中下游地区垂直运动异常和气流辐合异常     

湖南省四水流域水沙周期特征及其影响因素分析

采用复小波变换和M K非参数检验的方法分析了湖南省四水流域主要控制站1951~2011年径流量与输沙量周期规律和突变特征。结果表明：(1)湖南四水径流量存在多个波动增加和波动减少的波动变化现象,但无显著变化趋势;而输沙量虽然有一定的波动,但总体上呈波动减少变化态势,而且下降趋势较显著;(2)湘潭站、桃江站和桃源站径流量和输沙量存在20~25 a的第一主周期,而石门站径流量和输沙量的第一主周期不具有一致性,径流量主周期为2 a,输沙量主周期为13 a,但其径流量和输沙量第二、三主周期变化规律相吻合,均为3~5 a的周期;(3)大量的水利工程建设是导致输沙量减少的主要原因,径流量的变化与降水的变化规律较为一致     

面源磷负荷改进输出系数模型及其应用

传统的输出系数模型是模拟较大流域面源污染的有效手段,但它假设同一土地利用类型的输出系数相同,忽视了营养物径流和截留过程中其他流域特征对输出系数空间分布的影响,难以为流域分区管理提供依据。在传统输出系数模型基础上,引入产污因子（CI）和截留因子（RI）,校正地形、降雨、植被缓冲带对面源磷流失空间格局的影响。用改进输出系数模型模拟滇池流域面源磷负荷并将模拟结果应用于流域管理。结果表明,改进的输出系数模型能更好地模拟面源磷污染的空间格局,识别出面源总磷的关键风险区--湖滨平原地带以及与入滇河流邻近的山谷、台地。以2008年滇池流域面源总磷的模拟结果（3525 t）为基准,若单位面积磷肥施用量减少20%,面源总磷负荷将减少86%;若环湖公路内侧全部实现退耕还林或还草,面源总磷负荷将减少60%;若同时实施减少磷肥施用量和环湖公路内退耕两项措施,面源总磷负荷将减少130%     

Toxicity of sediment cores from Yangtze River estuary to zebrafish (<Emphasis Type="Italic">Danio rerio</Emphasis>) embryos

Toxicity evaluation is an important segment in sediment quality monitoring in order to protect aquatic organisms and human health. The purpose of this study is to assess the toxicity of sediments from three sediment cores in Yangtze River Estuary, China, using the zebrafish (Danio rerio) embryo tests. Fertilized zebrafish eggs were exposed to both whole sediments and sediment organic extracts prepared from collected sediments, in order to provide a comprehensive and realistic insight into the bioavailable toxicity potential of the sediments. As end points, development parameters (mortality, hatching rate, and abnormality) in the developing embryos were recorded during the 96-h exposure. The results showed that some samples increased mortality, inhibited the hatching of embryos, and induced morphological abnormalities. The embryonic toxicities presented serrated changes and irregular distribution with depth, which may be related to hydrodynamic effect and unstable environmental input. However, lethal and sub-lethal effects were more significant at the sub-surface sediments (10～40 cm), which indicated that the pollution is more serious in recent decades.     

Simultaneous separation of apigenin,luteolin and rosmarinic acid from the aerial parts of the copper-tolerant plant Elsholtzia splendens

Elsholtzia splendens is a copper-tolerant plant species which grows on copper deposits in China. The generation of a valuable E. splendens biomass on specific contaminated sites has become one of the promising phytotechnologies. The simultaneous separations of apigenin, luteolin, and rosmarinic acid yielded in the ethyl acetate extracts of the flowering aerial parts was achieved by the use of a macroporous resin, polyamide, and silicagel columns during chromatography. Chemical identification confirmed the structures based on the spectra of FTIR, NMR, and HPLC/ESI-MS. The isolated compounds of purity above 98.3 % were evaluated for their in vitro cytotoxic activities against human cancer cell lines including A549 (non-small lung), A431 (skin), and Bcap37 (breast). Among these compounds, luteolin and apigenin presented the best cytotoxic activities against A549, A431, and Bcap37 cells and, therefore, both could be the valuable products for the post-harvest processing of E. splendens biomass.     

Emission Impacts of Electric Vehicles

Alternative vehicular fuels are proposed as a strategy to reduce urban air pollution. In this paper, we analyze the emission Impacts of electric vehicles In California for two target years, 1995 and 2010. We consider a range of assumptions regarding electricity consumption of electric vehicles, emission control technologies for power plants, and the mix of primary energy sources for electricity generation. We find that, relative to continued use of gasoline-powered vehicles, the use of electric vehicles would dramatically and unequivocally reduce carbon monoxide and hydrocarbons. Under most conditions, nitrogen oxide emissions would decrease moderately. Sulfur oxide and particulate emissions would Increase or slightly decrease. Because other areas of the United States tend to use more coal in electricity generation and have less stringent emission controls on power plants, electric vehicles may have less emission reduction benefits outside California.     

Bio-immobilization of Cu and Zn in recirculated bioreactor landfill

Purpose  

To protect the environmental quality of soil, groundwater, and surface water near the landfill site, it is necessary to make an accurate assessment of the heavy metal mobility. This study aims to present the bio-immobilization behavior of heavy metals in landfill and provide some reference suggestion for the manipulation of heavy metal pollution control after closure.