城市轨道交通地下段引起居民室内振动的频谱特性分析

为了解城市轨道交通引起建筑物室内振动的特征及变化规律,对轨道交通沿线建筑物一层室内环境进行振动测量,将监测数据进行频谱分析并与国内标准比较。结果表明:采用《城市区域环境振动标准》(GB 10070—1988)中的限值评价室内振动,即使最大Z振级测量结果达标,居民的主观烦恼度依然较高;室内振动的1/3倍频程模式下,频谱主峰对应频率并不固定,一般为40、50、63、80 Hz;车辆运行高峰段和平峰段对居民室内振动频谱的谱型没有改变,载重大和车次密的高峰段不会带来振级总量和各分频量值的显著增加;近轨和远轨产生室内振动,其特征频谱谱型相同,量值上近轨大,远轨小;采用振级增量能够更准确地描述城市轨道交通对居民室内的振动影响。国内标准比较发现:各标准振动频谱考察范围不一致,测量指标和测量方法多样,评价结果也不一致,因此亟须修订相关标准,统一评价量,以满足城市轨道交通规划防治需求。     

北京地铁列车运行引起建筑室内振动污染特征与评价

以分频最大振级(VL max)和最大Z振级(VL Z max)作为评价量,结合相关标准,监测与评价北京市地铁列车运行引起的临近建筑室内振动。结果表明:北京市2条地铁线路的振动特征频率分别为25 Hz、31.5 Hz、40 Hz和63 Hz,以40 Hz为主;特征频率上振动加速度级(VAL)增量明显;VL max、VL Z max的大小既与频率计权因子不统一有关,也与地铁对建筑室内振动的影响程度及振动能量在不同中心频率上的分布差异直接相关;地铁隧道埋深较水平距离对地铁振动衰减作用显著;地铁振动监测与评价的频率范围可统一为对人体影响较大的1 Hz^80 Hz,并统一频率计权因子。     

变压器噪声对居民室内噪声影响分析和控制

变压器噪声对居民室内的影响，往往是通过建筑物固体传声和结构辐射噪声所引起，采取以隔振为主要控制手段的噪声治理措施，可以取得较为满意的降噪效果。     

城市轨道交通噪声评价方法及其限值的研究

根据城市轨道交通噪声时、空分布特点及污染规律,对轨道交通噪声评价量作了分析研究,提出了列车通过时的最大声级作为城市轨道交通噪声的评价量,并根据噪声时问分布特性曲线提出了与之相对应的等效声级简易计算方法.通过对上海轨道交通3号线沿线居民区的主、客观调查,得到主观烦恼度阈值和干扰睡眠阈值,提出了适用于我国城市轨道交通的环境噪声限值(建议).     

奎屯市主要交通干线噪声状况与分析

通过对奎屯市6条主要交通干线3年的交通噪声监测与分析，得出各条道路车流量、车型、车速和路况的差异。使交通噪声在空间上差异明显，各交通干道交通负荷不是很重，但二侧噪声污染却比较严重，而且污染水平逐年提高。     

特高压换流站噪声源测试与预测技术研究

科学识别和获取特高压换流站内主要噪声源特性,在此基础上对换流站噪声影响进行分析预测,用于换流站噪声评价、设计和防护。在复杂声场环境条件下,通过现场录波、噪声与振动同步测试等方法,结合噪声理论知识,识别出换流变压器的优势谱点为400 Hz,该点占整个频谱噪声贡献值90%以上,同时识别出交流滤波器场电抗器特征频率点与电抗器所滤除的谐波频率相一致,且换流变压器和交流滤波器场电抗器的声压与振动优势频点具有较强的相关性。根据噪声源特性,对其计算模型进行相应的改进,可提高换流站噪声预测结果的准确性。     

2018年春节北京市噪声污染分析

利用北京市87个噪声自动监测站点监测数据，分析2018年除夕夜(2月15日18：00—2月16日2：00)全市噪声排放水平。通过比较2013—2018年除夕夜噪声排放强度，结合北京市细颗粒物浓度变化分析，表明2018年除夕夜北京市噪声污染排放显著降低，2013—2018年噪声污染排放存在时空分布特征，除夕夜细颗粒物污染变化与噪声污染变化趋势较为吻合，作为主要污染源的烟花爆竹燃放在受到政策的限制后，除夕夜北京市声环境和空气环境同比大幅改善。     

由石油类应急监测现状探寻水中石油类监测的突破

突发环境事件发生后,对污染物质、污染物浓度、污染范围及其动态变化情况进行监测是环境应急监测的基本工作要求。在不能利用管理手段有效获取污染来源等信息的情况下,开展溯源应急监测成为突发环境事件处理处置的重要需求。然而通过资料调研及应急监测案例分析发现,石油类水体突发环境事件应急监测大多存在采样代表性不够、溯源手段不健全、特征污染物监测不全面,以及现行石油类监测方法不能完整说清污染状况等问题或不足。因此,建议通过优化整合水中石油类指标监测标准,构建与石油类污染特征相适应的技术规范及配套监测分析方法,以达到精准、全面反映石油类水体污染状况的目的。     

我国空气中挥发性有机物标准体系建设的对策和建议

介绍了挥发性有机物（VOCs）的界定与危害，以及美国、欧盟、日本 VOCs的排放标准、控制经验、效果、气体标准样品研究现状等。分析了我国 VOCs的污染、标准体系建设、标准样品等研究现状及存在的问题，提出我国应建立 VOCs筛选优控名单、制定并完善行业排放标准和监测方法体系，以及开展 VOCs气体标准样品研究等相关对策和建议。     

环境电磁辐射的监测方法

电磁辐射对环境的影响主要包括工频电场、工频磁场、无线电干扰以及对环境产生的噪声。根据《辐射环境保护管理导则电磁辐射监测仪器和方法》（HJ／T10．2—1996），对宜宾110kV吊黄楼变电站进行电磁环境监测，将监测所得结果对照国家规定的限值，对电磁污染水平进行评价。通过仪器的选择，监测点位的确定以及执行标准等方面的内容，比较系统的介绍了现行电磁辐射的环境监测方法。     

地铁振动引起的二次辐射噪声适用标准研究

研究了城市地铁产生的二次辐射噪声测量现状及评价方法,依据现行地铁二次辐射噪声监测相关标准,对城市地铁产生的二次辐射噪声进行测量,将JGJ/T 170—2009、GB 50118—2010和GB/T 50355—2018中规定的限值与地铁二次辐射噪声的特征频谱、环境影响评价以及噪声限值进行了对比分析。结果显示,现行标准限值在执行中存在一定的不完善之处,需要根据实测数据重新分析评价标准的适用性、准确性和合理性。结合当前噪声管理的社会需求,提出了声级增量和特征频谱增量的概念,并将分析结果与现行标准值进行了比较分析,表明声级增量和特征频谱增量能更好地反映二次辐射噪声的影响,对于地铁二次辐射噪声标准的制修订具有参考价值。     

隔声窗隔声性能的现场监测方法及效果初探

采用隔声窗作为典型道路的交通噪声控制措施，探索隔声性能的现场监测方法。分别选取真空玻璃窗与中空玻璃窗进行监测，两种隔声窗对交通噪声1000 Hz 和2000 Hz 两个倍频带的隔声量最大，真空玻璃隔声窗对500 Hz 倍频带及以下的噪声比中空玻璃隔声窗更有效，如果采用两种隔声窗进行组合，在全频带的隔声量达到25 dB。     

Erroneous mass transit system and its tended relationship with motor vehicular air pollution (An integrated approach for reduction of urban air pollution in Lahore)

Air pollution is threat to the lives of people living in big cities of Pakistan. In Lahore 1,250 people die annually because of air pollution.Mass transit system that can be put forth as solution to urban air pollution is contingent with right choice of system and its affiliation with motorized vehicles and nature of urban air pollution.Existing mass transit system in Lahore due to untrue operation causes surfeit discharge of motor vehicular carbon monoxide. Tended relationships of mass transit system with motorized vehicles and urban air pollution are quite noteworthy. The growing motor vehicles (a consequence of flawed public mass transit system) are potential source of urban air pollution. This paper attempts to highlight correlations and regression curves of existing mass transit system. Further it recommends a two facet approach for reduction of motor vehicular air pollution in Lahore.     

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。     

北京市高架道、桥交通噪声状况调查与对策研究

对北京市区内８１座道路立交桥和１１段高架道路的声环境状况进行了多方位的调研与实测。分析了高架道、桥附近声环境的地面水平分布特征、高层楼房垂直分布特征、昼夜时间分布特征及产生的原因。从增强城市总体规划与交通管理,注意沿街建筑功能配置与布局,加强临街住户门窗隔声效果,适当建设有效的道路隔声屏障等方面提出了城市发展中解决和控制交通噪声污染的对策建议。     

氮氧化物的污染控制对策

详细地介绍了日本针对不同的排放源－－固定源和流动源－－所采取的氮氧化物污染控制对策。对固定源，在实施全国统一的排放标准的基础上，对于一些工厂相对集中、污染问题严重的地区实施总量控制，同时积极促进技术革新以及降低氮氧化物的排放；对流动源所采取的措施有，确定不同车型汽车排放尾气递减的短期目标和长期目标，实施汽车氮氧化物法，积极推进低公害车的普及。通过采取上述措施，在日本，固定源排放的氮氧化物得到了较好     

Noise surveys of hand-held pneumatic rock drills in Hong Kong

A study of the noise generated by hand-held pneumatic rock drills at 15 road works locations in Hong Kong was conducted in 1989. The locations of road construction works were identified over one week period. Sound pressure levels (SPL) and band frequency analysis were measured with the integrated sound level meter at the level of the operator's ears. The sound levels for all 15 operators exceeded the local statutory limit of 90 dBA. The average sound level was 107.4 dBA and the corresponding continuous equivalent level adjusted to 8 hours or L _eq (8h) was 104.8 dBA. The sound levels for the octave frequencies from 125 Hertz to 8000 Hertz were all in excess of 90 dBA. Estimates of the risk of developing hearing impairment for conversation speech among the operators were 18% and 42% after 5 and 10 years of exposure, respectively. Although there is adequate statutory control to restrict and reduce the hazards caused by noise at road construction works to the workers and to the public at large, no noise control measures were noted at the work sites and none of the operators used hearing protection. This situation was compounded by the short-term nature of road works and the high mobility of the operators.     

Environmental concerns of desalinating seawater using reverse osmosis

This Critical Review on environmental concerns of desalination plants suggests that planning and monitoring stages are critical aspects of successful management and operation of plants. The site for the desalination plants should be selected carefully and should be away from residential areas particularly for forward planning for possible future expansions. The concerning issues identified are noise pollution, visual pollution, reduction in recreational fishing and swimming areas, emission of materials into the atmosphere, the brine discharge and types of disposal methods used are the main cause of pollution. The reverse osmosis (RO) method is the preferred option in modern times especially when fossil fuels are becoming expensive. The RO has other positives such as better efficiency (30-50%) when compared with distillation type plants (10-30%). However, the RO membranes are susceptible to fouling and scaling and as such they need to be cleaned with chemicals regularly that may be toxic to receiving waters. The input and output water in desalination plants have to be pre and post treated, respectively. This involves treating for pH, coagulants, Cl, Cu, organics, CO(2), H(2)S and hypoxia. The by-product of the plant is mainly brine with concentration at times twice that of seawater. This discharge also includes traces of various chemicals used in cleaning including any anticorrosion products used in the plant and has to be treated to acceptable levels of each chemical before discharge but acceptable levels vary depending on receiving waters and state regulations. The discharge of the brine is usually done by a long pipe far into the sea or at the coastline. Either way the high density of the discharge reaches the bottom layers of receiving waters and may affect marine life particularly at the bottom layers or boundaries. The longer term effects of such discharge concentrate has not been documented but it is possible that small traces of toxic substances used in the cleaning of RO membranes may be harmful to marine life and ecosystem. The plants require saline water and thus the construction of input and discharge output piping is vital. The piping are often lengthy and underground as it is in Tugun (QLD, Australia), passing below the ground. Leakage of the concentrate via cracks in rocks to aquifers is a concern and therefore appropriate monitoring quality is needed. Leakage monitoring devices ought to be attached to such piping during installation. The initial environment impact assessment should identify key parameters for monitoring during discharge processes and should recommend ongoing monitoring with devices attached to structures installed during construction of plants.