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41.
The spores of Cladosporium Link. are often present in the air in high quantities and produce many allergenic proteins, which may lead to asthma. An aerobiological spore monitoring program can inform patients about the current spore concentration in air and help their physicians determine the spore dose that is harmful for a given individual. This makes it possible to develop optimized responses and propose personalized therapy for a particular sensitive patient. The aim of this study was to assess the extent of the human health hazard posed by the fungal genus Cladosporium. For the first time, we have determined the number of days on which air samples in Poland exceeded the concentrations linked to allergic responses of sensitive patients, according to thresholds established by three different groups(2800/3000/4000 spores per 1 m~3 of the air). The survey was conducted over three consecutive growing seasons(April–September, 2010–2012) in three cities located in different climate zones of Poland(Poznan, Lublin and Rzeszow). The average number of days exceeding 2800 spores per cubic meter(the lowest threshold) ranged from 61(2010) through 76(2011) to 93(2012), though there was significant variation between cities. In each year the highest concentration of spores in the air was detected in either Poznan or Lublin, both located on large plains with intensive agriculture. We have proposed that an effective, science-based software platform to support policy-making on air quality should incorporate biological air pollutant data,such as allergenic fungal spores and pollen grains.  相似文献   
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Yang, Yang, Theodore A. Endreny, and David J. Nowak, 2011. iTree‐Hydro: Snow Hydrology Update for the Urban Forest Hydrology Model. Journal of the American Water Resources Association (JAWRA) 47(6):1211–1218. DOI: 10.1111/j.1752‐1688.2011.00564.x Abstract: This article presents snow hydrology updates made to iTree‐Hydro, previously called the Urban Forest Effects—Hydrology model. iTree‐Hydro Version 1 was a warm climate model developed by the USDA Forest Service to provide a process‐based planning tool with robust water quantity and quality predictions given data limitations common to most urban areas. Cold climate hydrology routines presented in this update to iTree‐Hydro include: (1) snow interception to simulate the capture of snow by the vegetation canopy, (2) snow unloading to simulate the release of snow triggered by wind, (3) snowmelt to simulate the solid to liquid phase change using a heat budget, and (4) snow sublimation to simulate the solid to gas phase via evaporation. Cold climate hydrology routines were tested with research‐grade snow accumulation and weather data for the winter of 1996‐1997 at Umpqua National Forest, Oregon. The Nash‐Sutcliffe efficiency for open area snow accumulation was 0.77 and the Nash‐Sutcliffe efficiency for under canopy was 0.91. The USDA Forest Service offers iTree‐Hydro for urban forest hydrology simulation through http://www.iTreetools.org .  相似文献   
44.
This study was aimed at investigating the physicochemical and microbiological changes that took place during the ageing process of spent bleaching earth in the presence of autochthonous microorganisms. Research material included fresh spent bleaching earth (SBE0) and the same material after 3 years of storage at the constant temperature of 20 °C, without aeration and moistening (SBE3). Changes in the chemical composition of analysed waste material were observed during its ageing process point to a spontaneous bioconversion of fat substance towards formation and/or release of free saturated fatty acids C16:0 and C18:0 (14.3 g 100 g?1 D.M.), triterpenes (8.48 g 100 g?1 D.M.), cholesterol (3.29 g 100 g?1 D.M.), small quantities of carbohydrates and esters (0.80 g 100 g?1 D.M.). This process was accompanied by other changes in physicochemical parameters of the waste material, such as colour, odour and viscosity, decrease in fat content from 28.27 to 24.6 % and that of soluble forms of metals (Mo, Cu, Fe, Zn, Ni, Cr and Mn), ranging from 25 to 75 %, and an increase in pH, from 3.85 to 4.2. At the same time, changes in the microbial consortium were observed.  相似文献   
45.
常见离子对蛋壳粉吸附溶液中磷的影响   总被引:1,自引:0,他引:1  
研究了水体中常见离子对蛋壳粉吸附溶液中磷的影响.实验结果表明,SO2-4、Cl-和NO-3的存在,对天然蛋壳粉吸附磷过程产生协同作用,但协同作用不明显;HCO-3表现出吸附抑制作用;Ca2+和Mg2+表现出较为显著的吸附协同作用,其中Ca2+最为显著;NH+4离子存在时,几乎不产生影响.富集系数和吸附平衡下降率均可有效表述常见离子对蛋壳粉吸附磷过程的影响程度.  相似文献   
46.
我国四个大气背景点颗粒物浓度及其元素分布特征   总被引:2,自引:0,他引:2  
选择全国由南至北的4个大气背景站(广东南岭、湖北神农架、山西庞泉沟和吉林长白山),于2013年分4个季度同步采集环境空气颗粒物PM10和PM2.5样品,采用微波消解电感耦合等离子体质谱法测定滤膜样品中60余种元素.结果表明,4个背景点PM2.5日均质量浓度平均值为17μg·m-3,PM10为29μg·m-3,低于《环境空气质量标准》(GB 3095—2012)规定的一级浓度限值.第一季度的PM10和PM2.5最高,除长白山第三季度高于第四季度之外,其他3个点位均呈现第二季度第四季度第三季度的趋势.PM2.5和PM10二者呈线性正相关,4个季度的PM2.5/PM10比值均小于0.5,第二、第三季度较高,而第一、第四季度较低.PM10和PM2.5中元素随季节变化不大,PM2.5含量在同一水平上低于PM10.Na、Mg、Al、S、K、Ca、Fe、Zn质量浓度在0.1—10μg·m-3之间,P、Ti、Mn、Ni、Cu、Ba、Pb质量浓度在10—100 ng·m-3之间,Cd、Co、Ge、Ga、Zr、Sr、V等质量浓度在0.01—10 ng·m-3之间.K、Al、Ca含量大于10%,S、Mg、Na、Fe、Zn、Pb、Mn含量大于1%,Cu、P、Ba、Ti量介于0.5%—1%,其他痕量元素含量所占比例小于0.5%.  相似文献   
47.
全氟化合物前体物质生物转化与毒性研究进展   总被引:1,自引:0,他引:1  
全氟化合物前体物质在环境和人体中广泛分布,是全氟化合物污染的重要间接来源.由于这些前体物质可以转化为具有生物富集性、多器官毒性,并且半衰期更长的全氟磺酸(PFSAs)和全氟烷酸(PFCAs),近年来受到了越来越多的关注.此外,一些全氟化合物前体物质自身或者代谢中间体也具有一定的生物学毒性,如类激素作用、蛋白偶联、细胞毒性等等,这些都可能造成人群暴露的潜在健康危害.本篇综述针对于全氟烷酸和全氟磺酸类的前体物质,总结了该类化合物在环境分布、生物转化和相关毒性研究方面的最新进展.  相似文献   
48.
Bentonites are preferred materials for use as engineered barriers for high-level nuclear waste repositories. Simulation of geochemical processes in bentonite is therefore important for long-term safety assessment of those repositories. In this work, the porewater chemistry of a bentonite sample subject to simultaneous heating and hydration, as studied by Cuevas et al. [Cuevas, J., Villar, M., Fernández, A., Gómez, P., Martín, P., 1997. Porewaters extracted from compacted bentonite subjected to simultaneous heating and hydration. Applied Geochemistry 12, 473-481.], was assessed with a non-isothermal reactive transport model by coupling the geochemical software PHREEQC2 with the object-oriented FEM simulator GeoSys/RockFlow. Reactive transport modelling includes heat transport, two-phase flow, multicomponent transport and geochemical reactions in the liquid phase, i.e. ion exchange, mineral dissolution/precipitation and equilibrium reactions. Simulations show that the easily soluble minerals in bentonite determine the porewater chemistry. Temperature affects both two-phase flow and geochemical reactions. Porosity change due to dissolution/precipitation is low during the experiment. However, changes of the effective porosity caused by bentonite swelling can be very large. The simulated results agree well with the experimental data.  相似文献   
49.
Residues of endosulfan insecticide (-and -isomers, and endosulfan sulphate) were determined in the livers of catfish from a cotton growing area during the summer and winter of 1988. The concentration of total endosulfan residues found in the fish was up to 0.31 mg kg-1 wet wt. It decreased in winter with a maximum 0.02 mg kg-1 wet wt. The difference in endosulfan residues between seasons was statistically significant (ANOVA,p<0.01).  相似文献   
50.
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