城市典型高架复合道路交通噪声污染模拟及防治对策

与一般城市道路相比,城市高架复合道路通行能力大、行车速度高、车辆行驶状态复杂,交通噪声污染极为突出。选取深圳市典型的高架复合道路——春风高架和爱国高架进行实地监测,同时运用SoundPLAN软件模拟其噪声污染现状与安装声屏障后的降噪效果。根据监测模拟结果,从合理进行道路规划、装设声屏障和铺设低噪声路面等方面提出高架复合道路噪声污染控制的对策建议。     

温室气体光声光谱检测系统的建立及效果分析

“双碳”目标下,温室气体在线长期稳定监测技术是全面掌握温室气体排放及其环境、气候效应,并预测未来变化趋势的重要保障。为了实时在线监测工业生产现场等环境温室气体浓度及其变化趋势,及时采取相应措施,在分析光声光谱信号产生机理及多组分气体混合监测原理的基础上,根据温室气体的主要成分,分析其吸收光谱特性,基于光声光谱的多组分温室气体的定性和定量监测技术,搭建温室气体光声光谱在线监测实验平台,分析监测器内部噪声和环境温度、湿度等外部影响因素,并通过现场测试,分析试验数据,应用吸附法降低内外部因素的影响。结果表明,对称安装传声器和非共振式光声腔能有效削弱外部噪声对测试结果的影响;空气净化器能降低空气中水蒸气和其他气体对测试结果的影响;低、高浓度混合气体监测结果偏差均小于0.5,与GC测试结果偏差小于10%。应用光声光谱技术的环境温室气体监测技术监测范围宽,选择性好,且监测精度达10^-6,适用于环境温室气体浓度在线监测。     

南京市城市典型道路交通噪声控制措施效果初探

针对南京市典型道路的交通噪声控制措施,分别选取低噪声路面、声屏障、隔声窗3种噪声控制措施进行监测,监测显示低噪声路面对整体声级降噪有限,声屏障对于1kHz倍频带以上的中高频隔声相对较好,真空玻璃隔声窗能对低频噪声有显著改善。     

背景修正对噪声监测结果影响的探讨与实践

分析了背景噪声测量不确定性以及背景修正对噪声监测结果的影响,提出,在实际噪声测量工作中,当测量值与背景值的差值≥3 dB且测量值修正结果与排放限值非常接近时,以及当测量值与背景值的差值3 dB且测量值与排放限值的差值≤4 dB时,对背景噪声进行重复测量,计算背景噪声测量不确定性,利用公式法进行定量背景修正的建议,并在噪声测量和数据处理过程中降低背景噪声测量不确定性,从而减少背景修正对噪声测量结果的影响,更加客观地反映噪声的真实情况。     

突发性背景噪声的修正计算分析

噪声测量过程中蝗受背景噪声的影响,而对于突发性背景噪声因其重现性差,实际操作上的“非同时性”给背景噪声的测量结果及修正均带来一些失准问题。为此对突发性背景噪声的校正问题提出初步建议。     

北京市公交车噪声测试与分析

公交车已成为当前北京市道路交通噪声的主要束源之一,针对公交车声源模型缺乏而沿用大型车声源模型所致的噪声预测误差问题,在北京市选取了两类常见公交车进行了537辆车的单车通过噪声测试,在无效数据剔除和背景噪声修正后,利用回归分析法获得了北京市公交车声源模型,通过与现有《公路建设项目环境影响评价规范》中大型车声源模型的比较,显示出建立北京市公交车噪声声源模型的必要性。基于《公路建设项目环境影响评价规范》中的道路交通噪声预测方法,提出了符合北京市实际情况的道路交通噪声预测模型。     

基于可靠度的变压器声功率遗传算法研究

换流变压器是高压直流换流站中主要的噪声源,对换流变压器噪声的预测精度直接影响到后期整个换流站噪声预测模型的准确性,因此,准确获得换流变压器的声功率至关重要。根据《声学 户外声传播衰减 第2部分:一般计算方法》(ISO 9613-2:1996)中的户外声传播声功率计算方法,构建了声源声功率反推数学模型。利用某变压器周围大量测点现场实测数据,结合可靠度理论,识别并剔除了实测点中受相干声场影响较大的点,实现了换流变压器声功率反演计算,并对测点个数的选取进行了初步研究及优化。与其他声功率测量方法相比,该方法操作简单,对仪器设备要求较低,适用于复杂的声学环境,具有一定的应用前景。     

背景噪声在边界噪声测量中的影响及修正

1现行方法未考虑非稳态背景噪声影响 ,经计算得表 1数据 ,可直观选取δ值 :表 1　 ︾与 ηL 的关系 (d B)ΔL 3 .0～ 3 .2 3 .3～ 3 .94.0～ 4.84.9～ 6.0 6.1～ 7.98.0～ 1 1 .0δ 3 .0～ 2 .82 .7～ 2 .3 2 .2～ 1 .81 .7～ 1 .3 1 .2～ 0 .80 .7～ 0 .3δ取值 3 .0 2 .5 2 .0 1 .5 1 .0 0 .5表中δ由ΔL确定 ,ΔL=L- L0 ,式中 L为边界噪声等效声级 ;L0 为同一地点背景噪声等效声级。2背景噪声较高且波动较大时 ,适当延长 L和 L0 的测量时间。背景噪声在边界噪声测量中的影响及修正@金庆先$昆山市环境监测站!江苏昆山215300…     

居住区的交通噪声问题及防治方法

首先分析交通噪声对居住区声环境的影响及当前存在的问题，然后重点探讨相应的防治方法，特别是在居住区的规划中，以对噪声不敏感的建筑物和利用绿化隔离带形成小区周边的声屏障、小区道路系统防止城市交通穿越、加强住宅建筑设计中隔声构造处理等方面提出了具体的技术措施．     

多功能声学校准器——B＆K4226

丹麦B＆K公司于1989年开发的B＆K4226型多功能声校准器能用于测试声级计、噪声剂量计、传声器以及其它有关仪器的特性.4226能产生从31.5Hz至16kHz(以倍频程档级)的电信号和12.5kHz声信号,还能模拟恒定的无规入射场和自由场,并能提供一个非常准确的反A计权修正,使用者只需检查显示结果是否在规定的误差范围内,如果需进行频率扫描可外接信号发生器.     

Quantitative detection of nitrate in water and wastewater by surface-enhanced Raman spectroscopy

The presence of inorganic nitrogen species in water can be unsuitable for drinking and detrimental to the environment. In this study, a surface-enhanced Raman spectroscopy (SERS) method coupled with a commercially available gold nanosubstrate (a gold-coated silicon material) was evaluated for the detection of nitrate and nitrite in water and wastewater. Applications of SERS coupled with gold nanosubstrates resulted in an enhancement of Raman signals by a factor of ～10⁴ compared to that from Raman spectroscopy. The new method was able to detect nitrate with linear ranges of 1–10,000 mg NO₃ ^?/L (R ²?=?0.978) and 1–100 mg NO₃ ^?/L (R ²?=?0.919) for water and wastewater samples, respectively. Among the common anions, phosphate appeared to be the major interfering anion affecting nitrate measurement. Nevertheless, the percentage error of nitrate measurement in wastewater by the proposed SERS method was comparable to that by ion chromatography. The nitrate detection limits in water and wastewater samples were about 0.5 mg/L. The SERS method could simultaneously detect sulfate, which may serve as a reference standard in water. These results suggested that the SERS coupled with nanosubstrates is a promising method to determine nitrate concentrations in water and wastewater.     

An LCA-based environmental impact assessment model for regulatory planning

Assessing the environmental impact (EI) of regulatory planning (a lower tier in the Chinese urban planning system) has significant implications for improving the environmental performance of the future built environment. Current environmental impact assessments generally focus on microscale and macroscale, while mesoscale studies at region level are lacking. To fill this gap, this paper proposes an LCA-based environmental impact assessment model for regulatory planning, which focuses on embodied EI of urban construction and operational EI associated with the operation of the built environment. To ensure the regulatory plans both meet the environmental limits and fit well with environmental policy requirements, this paper also presents a new impact analysis method by integrating environmental carrying capacity analysis and distance to target method. The Statutory Plan of Shenzhen Futian Free Trade Zone 03-T2 is used as a case study to test and demonstrate the applying process and functions of the proposed method. Results indicate that the proposed model can effectively quantify the future environmental impact associated with a regional development plan, and can potentially be used as a tool for urban administrators to make decisions on regulatory planning revision and provide references for environmental management.     

环境监测实验室方法确认过程中常见问题探讨

根据实验室资质认定对于方法确认的要求，结合环境监测实验室的特点，提出了新项目方法确认的具体步骤，并分析了其中存在的常见问题。指出在方法确认过程中，应严格按照标准方法和监测技术规范进行全过程试验，尤其不能忽视采样现场实验、空白实验和检出限的测定。建议在精密度与准确度检验过程中，使用高、中、低不同浓度的有证标准样品，实际样品加标回收，比对试验（方法比对、人员比对、实验室间比对），增加分析次数等多种手段，确保新项目开展的可靠性。     

Integrated Environmental Assessment of the Mid-Atlantic Region with Analytical Network Process

A decision analysis method for integrating environmental indicators was developed. This was a combination of Principal Component Analysis (PCA) and the Analytic Network Process (ANP). Being able to take into account the interdependency among variables, the method was capable of ranking ecosystems in terms of environmental conditions and suggesting cumulative impacts across a large region. Using data on land cover, population, roads, streams, air pollution, and topography of the Mid-Atlantic Region of the United States, we were able to point out areas which were in relatively poor condition and/or vulnerable to future deterioration regarding various environmental aspects. The method offered an easy and comprehensive way to combine the strengths of conventional multivariate statistics (PCA) and decision-making science tool (ANP) for integrated environmental assessment.     

华北地区滨海湿地生态系统健康评价体系构建研究

以华北地区滨海湿地中的天津宁河七里海湿地为例,以PSR模型作为评价基础框架,运用可持续发展的理论、环境生态学、城市生态学、景观生态学等科学理论,结合社会经济资料收集、地面数据的采集与生态环境现状调查,应用层次分析法(AHP),在咨询专家意见的基础上,利用T L Saaty的标度法,构建了华北地区滨海湿地生态系统健康评价体系。体系由压力子系统、状态子系统、响应子系统构成,共筛选出三大类共计19项综合指标,其中压力指标6项、状态指标9项、响应指标4项。通过实际验证,该评价体系能客观地反映出湿地生态系统健康水平,可为环境管理部门的科学决策以及湿地的可持续发展提供技术支持,可供其他滨海地区湿地评价时参考。     

Iodide-assisted total lead measurement and determination of different lead fractions in drinking water samples

Lead and its compounds are toxic and can harm human health, especially the intelligence development in children. Accurate measurement of total lead present in drinking water is crucial in determining the extent of lead contamination and human exposure due to drinking water consumption. The USEPA method for total lead measurement (no. 200.8) is often used to analyze lead levels in drinking water. However, in the presence of high concentration of the tetravalent lead corrosion product PbO(2), the USEPA method was not able to fully recover particulate lead due to incomplete dissolution of PbO(2) particles during strong acid digestion. In this study, a new procedure that integrates membrane separation, iodometric PbO(2) measurement, strong acid digestion and ICP-MS measurement was proposed and evaluated for accurate total lead measurement and quantification of different lead fractions including soluble Pb(2+), particulate Pb(II) carbonate and PbO(2) in drinking water samples. The proposed procedure was evaluated using drinking water reconstituted with spiked Pb(2+), spiked particulate Pb(II) carbonate and in situ formed or spiked PbO(2). Recovery tests showed that the proposed procedure and the USEPA method can achieve 93-112% and 86-103% recoveries respectively for samples containing low PbO(2) concentrations (0.018-0.076 mg Pb per L). For samples containing higher concentrations of PbO(2) (0.089-1.316 mg Pb per L), the USEPA method failed to meet the recovery requirement for total lead (85-115%) while the proposed method can achieve satisfactory recoveries (91-111%) and differentiate the soluble Pb(2+), particulate Pb(II) carbonate and PbO(2).     

Development and preparation of lead-containing paint films and diagnostic test materials

Lead in paint continues to be a threat to children's health in cities across the United States, which means there is an ongoing need for testing and analysis of paint. This ongoing analytical effort and especially development of new methods continue to drive the need for diagnostic testing materials that provide the analytical challenges of real-world paints. To this end, 31 different types of paint test materials were developed and prepared. Preparation of the materials included development of lead-containing paint films yielding an overall relative standard error for one individual test sample being less than 10%. The 31 diagnostic test materials prepared with these paint films included two lead pigments; lead concentrations from nominally 0 to 2.0 mg lead/cm(2) (0 to 5% lead by weight); overlayers of both "lead-free," oil-based and water-based paints; Al, Ba, and Mg as potential chemical interferents; red and black potential color interferents; and substrates of wood, metal, masonry, and plaster. These materials challenge each step in method development and evaluation, including paint sample collection and preparation, lead extraction, and measurement of solubilized lead. When the materials were used to test performance of a new lead-in-paint testing method based on extraction using a rotor/stator method and measurement using turbidimetry, the results agreed to within ±20% of the expected lead values for 30 out of 31 of the diagnostic test materials, thereby demonstrating their levels of quality and utility.     

LugDown法设备性能的改进与完善方法

介绍了用于柴油车排气检测的加载减速工况（LugDown）法设备的构成与测量原理，分析了 LugDown 法设备在加载、功率扫描控制、排气测量控制等方面存在的问题。对照国标要求，结合 LugDown法设备的工作特点，探讨了在功率扫描性能、寄生滑行性能、排气测量过程控制、测试档位选择与扫描起始速度控制等方面的改进与完善方法。     

艾比湖流域核心区景观生态功能区划及生态调控措施研究

在探讨了景观生态功能区划的概念、原则及区划方法的基础上，以新疆艾比湖流域核心区为对象，采用叠置法并利用“3S”技术对研究区进行了自下而上的景观生态功能区的划分，共划分出4个景观生态功能区和9个景观生态功能亚区。分析了各景观功能区的主导生态功能、保护目标，并有针对性地提出了景观生态调控的工程措施和管理措施，为恢复和重建艾比湖流域景观生态安全格局提供科学的参考依据。     

Mathematical models for accurate prediction of atmospheric visibility with particular reference to the seasonal and environmental patterns in Hong Kong

Atmospheric visibility impairment has gained increasing concern as it is associated with the existence of a number of aerosols as well as common air pollutants and produces unfavorable conditions for observation, dispersion, and transportation. This study analyzed the atmospheric visibility data measured in urban and suburban Hong Kong (two selected stations) with respect to time-matched mass concentrations of common air pollutants including nitrogen dioxide (NO(2)), nitrogen monoxide (NO), respirable suspended particulates (PM(10)), sulfur dioxide (SO(2)), carbon monoxide (CO), and meteorological parameters including air temperature, relative humidity, and wind speed. No significant difference in atmospheric visibility was reported between the two measurement locations (p > or = 0.6, t test); and good atmospheric visibility was observed more frequently in summer and autumn than in winter and spring (p < 0.01, t test). It was also found that atmospheric visibility increased with temperature but decreased with the concentrations of SO(2), CO, PM(10), NO, and NO(2). The results showed that atmospheric visibility was season dependent and would have significant correlations with temperature, the mass concentrations of PM(10) and NO(2), and the air pollution index API (correlation coefficients mid R: R mid R: > or = 0.7, p < or = 0.0001, t test). Mathematical expressions catering to the seasonal variations of atmospheric visibility were thus proposed. By comparison, the proposed visibility prediction models were more accurate than some existing regional models. In addition to improving visibility prediction accuracy, this study would be useful for understanding the context of low atmospheric visibility, exploring possible remedial measures, and evaluating the impact of air pollution and atmospheric visibility impairment in this region.