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1.
介绍了简易瞬态工况法相对于双怠速法的技术优势,分析了该方法排气检测过程中的常见问题与作弊手段。提出以质量控制为基础,采取检测全过程防舞弊措施;与机动车排放监督管理系统建设相结合,对检测设备软件版本实施统一监控;通过实时数据分析,建立检测工位前端防舞弊控制机制;对检测数据分类统计与分析,促进检测工作公正与规范;借助视频监控手段,实现对检测过程的实时监管;加强日常巡查,促进监管工作体系持续完善等建议。  相似文献   

2.
针对简易瞬态工况法机动车尾气排放检测过程中层出不穷的违规检测现象,为对其检测过程实施有效监管,通过分析简易瞬态工况法的检测原理,筛选出可用于监管的车辆基准质量、(CO+CO2)浓度、O2浓度、实时检测尾气流量4个参数,分析其用于监管的原理和理由,并通过五气分析仪漏气实验和实测尾气流量异常案例验证其监管可行性,以期为监管...  相似文献   

3.
募集100辆点燃式发动机在用汽车进行遥感法和高怠速法尾气排放对照检测试验。结果表明,多数车辆CO遥测值比高怠速值大,HC则相反。通过对高怠速值(y)与遥测值(x)进行回归分析,得到CO的回归方程为y=0.81x+453.03,t检验显示方程具有线性(α=0.10)。如果将两种方法配合使用,可以有效提高机动车尾气排放日常管理的效果。  相似文献   

4.
在某特大城市机动车检验站筛选了123台轻型汽油车,依据《汽油车污染物排放限值及测量方法(双怠速法及简易工况法)》(GB 18285—2018)开展燃油蒸发控制系统泄漏测试,定量研究典型车型的燃油蒸发系统的现状及泄漏原因。结果表明,由于燃油系统硬管连接或碳罐遮挡造成无法进行后续泄漏测试的车辆约占14%;油箱盖加压测试合格率为95%;不合格车辆主要为10 a以上老旧车辆,合格车辆中加压损失与年均行驶里程(VKT)呈正相关,VKT每增加1 000 km,油箱盖压力损失约为9.9 Pa;加油口加压测试显示,各排放阶段(除国六外)的合格率为44%~75%。  相似文献   

5.
针对双怠速法机动车尾气排放检测过程中经常大量出现过量空气系数(λ)不合格现象,结合相关标准和工作实践对影响检测结果的因素进行分析。结果显示,取样管路的气密性差、系统响应时间未达标准、测试软件程序设置错误、高怠速转速设置不合理及由于车辆特性导致的选用标准及操作错误均会导致λ测试结果超标,影响双怠速检测法的准确性。  相似文献   

6.
在用机动车尾气检测新技术亮相   总被引:1,自引:0,他引:1  
既能够检测出汽车排放污染物的总量,又能够最终实现网络实时监测,且成本适中,这就是新型在用机动车尾气检测技术——简易瞬态工况检测法(即V mas)。在2007年6月3日召开的“在用机动车尾气检测新技术恳谈会”上,我国在用车尾气检测知名专家一致认为,为了有效控制在用车污染物排放总量、确保空气质量不再恶化并逐步好转,国家应尽快推动这一技术的普遍应用。  相似文献   

7.
机动车尾气排放检测方法对比分析   总被引:1,自引:2,他引:1  
通过怠速、双怠速法对机动车尾气检测试验和数据对比分析表明,不同车龄段的电喷型轿车采用怠速法检测尾气达标率在73.3%~93.5%之间;双怠速法检测尾气达标率在40.0%~82.6%之间.不同车龄段的化油器型轿车采用怠速法检测尾气达标率在25.0%~57.1%之间;双怠速法检测尾气达标率在18.8%~57.1%之间.指出双怠速法对化油器车辆尾气控制同样有效果,双怠速法对筛选高污染车辆比怠速法更严格和科学.  相似文献   

8.
序号名   称标准类别进展情况 计划发布时间1农用运输车自由加速烟度排放限值及测量方法国家标准已批准即将发布 2 0 0 22汽车加速行驶车外噪声限值及测量方法国家标准已批准即将发布 2 0 0 23机场环境影响评价技术导则行业标准已通过技术审查 2 0 0 24摩托车排气污染物排放限值及测量方法 (工况法 )国家标准已通过技术审查 2 0 0 25轻便摩托车排气污染物排放限值及测量方法 (工况法 )国家标准已通过技术审查 2 0 0 26摩托车和轻便摩托车怠速污染物排放限值及测量方法国家标准已通过技术审查 2 0 0 27车用点燃式发动机和点燃式发动机汽车…  相似文献   

9.
根据哈尔滨某检测站的工况法排放检测数据,用SPSS数据分析软件对符合DB11/122—2006标准中规定的不同类别车辆的检测数据分别进行统计分析。结果表明,若在哈尔滨地区借鉴该标准,I类车与Ⅲ类车的部分限值需要调整,这为其他地区设定适合的限值提供了参考。  相似文献   

10.
随着机动车保有量的增加,机动车尾气污染日渐凸显,对城市环境空气质量带来巨大压力,需要出台行之有效的措施来降低或减少机动车尾气排放带来的危害。机动车尾气排放管理方案的制定要结合"车、油、路"等多个角度考虑,防、治结合,才能有效减少城市机动车尾气排放。  相似文献   

11.
Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor 3H, 90Sr, total U, 238Pu, 239, 240Pu,241Am, and 137Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10-3 mSv y-1and 1.6 × 10-3 mSv y-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10-4 mGyd-1 and 4.7 × 10-4 mGy d-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines.  相似文献   

12.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

13.
Metal concentrations in deciduous tree leaves from urban areas in Poland   总被引:1,自引:0,他引:1  
Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves.  相似文献   

14.
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ 15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ 15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ 15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ 15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas, the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ 15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R 2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ 15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ 15N of Spartina relates with the integrated, watershed-sea nitrogen inputs.  相似文献   

15.
We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test theactivity of arbuscular mycorrhizal (AM) fungi in these soils.Soil samples were taken from (1) front of the shooting house(HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantagolanceolata) growing naturally within the shooting ranges werealso collected and the colonization of its roots by mycorrhizalfungi was measured. The number of AM spores in the soils wassignificantly reduced concomitant with the increase in thedegree of soil contamination with metals. In Zuchwil,mycorrhizal fungi equally colonized roots of Ribwort plantainsampled from BACKSTOP and HOUSE. In Oberuzwil, however, plantsfrom BACKSTOP had lower colonization when compared with thosesampled from HOUSE. Colonization of leek was strongly reducedin the BACKSTOP soil of Zuchwil and slightly reduced in theBACKSTOP soil of Oberuzwil when compared with plants grown inrespective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb andZn in the leaves of leek grown in the BACKSTOP soil was withinthe range considered toxic for human consumption. This pointsto the high degree of bio-availability of these metal in thesesoils. Significant decrease in the number of mycorrhizal sporesin the BACKSTOP soils in Zuchwil and the low colonization ofleek roots grown in these soils point to possible changes inthe species diversity of mycorrhizal fungi in these soils.  相似文献   

16.
Concentrations of 13 radionuclides (137Cs, 129I, 60Co, 152Eu, 90Sr, 99Tc, 241Am, 238Pu, 239,249Pu, 234U, 235U, 236U, 238U were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965–1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were 137Cs, 241Am, 239,249Pu, 234U, 235U, 236U, and 238U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for 137Cs; octopus was the only species with detectable levels of 137Cs (0.262 ± 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in 241Am and 239,240Pu, and almost no samples above the MDA for 238Pu and 236U. Horse mussels had significantly higher concentrations of 234U (0.844 ± 0.804 Bq/kg) and 238U (0.730 ± 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as ‘shellfish’, for comparative purposes in determining geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota.  相似文献   

17.
Kelp may be useful as a bioindicator because they are primary producers that are eaten by higher trophic level organisms, including people and livestock. Often when kelp or other algae species are used as bioindicators, the whole organism is homogenized. However, some kelp can be over 25 m long from their holdfast to the tip of the blade, making it important to understand how contaminant levels vary throughout the plant. We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in five different parts of the kelp Alaria nana to examine the variability of metal distribution. To be useful as a bioindicator, it is critical to know whether levels are constant throughout the kelp, or which part is the highest accumulator. Kelp were collected on Adak Island in the Aleutian Chain of Alaska from the Adak Harbor and Clam Cove, which opens onto the Bering Sea. In addition to determining if the levels differ in different parts of the kelp, we wanted to determine whether there were locational or size-related differences. Regression models indicated that between 14% and 43% of the variation in the levels of arsenic, cadmium, chromium, manganese, mercury, and selenium was explained by total length, part of the plant, and location (but not for lead). The main contributors to variability were length (for arsenic and selenium), location (mercury), and part of the plant (for arsenic, cadmium, chromium and manganese). The higher levels of selenium occurred at Clam Cove, while mercury was higher at the harbor. Where there was a significant difference among parts, the holdfast had the highest levels, although the differences were not great. These data indicate that consistency should be applied in selecting the part of kelp (and the length) to be used as a bioindicator. While any part of Alaria could be collected for some metals, for arsenic, cadmium, chromium, and manganese a conversion should be made among parts. In the Aleutians the holdfast can be perennial while the blade, whipped to pieces by winter wave action, is regrown each year. Thus the holdfast may be used for longer-term exposure for arsenic, cadmium, chromium and manganese, while the blade can be used for short-term exposure for all metals. Cadmium, lead and selenium were at levels that suggest that predators, including people, may be at risk from consuming Alaria. More attention should be devoted to heavy metal levels in kelp and other algae from Adak, particularly where they may play a role in a subsistence diets.  相似文献   

18.
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.  相似文献   

19.
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).  相似文献   

20.
土壤和底泥中砷、铬、锰测定的前处理技术   总被引:6,自引:0,他引:6  
试验了土壤和底泥中砷的前处理技术,其目的是能对土壤、底泥中砷、铬、锰在一次前处理中制备成试液,比色法分析。试验表明,用H2SO4-H3PO4-H2O2进行前处理是可行的。方法简单、挥发酸雾少,用标准参考物质检验证明,分解完全,数据准确,有粒较好一致性。  相似文献   

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