公路交通噪声预测的神经网络模型

利用多条国道、省道公路交通噪声的实测数据，建立了一个公路交通噪声预测的神经网络模型，能够同时预测公路交通噪声的等效连续声级、统计声级和标准偏差，预测值和实测值基本相符，该模型为公路交通噪声的预测、治理和控制提供了良好的条件。     

紫花苜蓿在柴油污染土壤中的萌发状况

选择以柴油作为土壤污染物，以单-外源环境因子污染水平为主要调控因子，采用室内盆栽试验的方法并且以不同质量分数的柴油污染土壤，在此情况下观察不同土壤柴油污染质量分数控制下紫花苜蓿种子的萌发与生长情况。结果表明，紫花苜蓿种子发芽抑制率与土壤柴油污染质量分数呈现指数线性相关关系，并且发现苜蓿发芽之后，高质量分数柴油处理组的幼苗出现黄叶和干枯现象。文章最后从土壤内柴油和柴油在土壤-大气界面间的迁移对种子萌发的影响进行了探讨。     

第五届全国噪声与振动控制工程学术会议在京举行

由中国声学学会环境声学分科学会、中国环境科学学会环境工程学会、中国环保工业学会噪声与振动控制委员会、中国劳动保护科学技术学会噪声与振动控制专业委员会联合举办的第五届全国噪声与振动控制工程学术会议于一九九○年十二月十三日至十六日在北京举行,参加会议的正式代表150人,特邀代表14人,来自16个省市,88个单位.收到论文96篇,会上交流了88篇.声学界的老前辈马大猷、杜连耀、车世光、于勃、吴大胜、严济宽、朱继梅、汪明清等教授以及国家环保局、上述四个学会的负责人应邀参加了会议.马大猷教授为大会作了《噪声控制     

利用餐饮业废油脂制造生物柴油

世界的石油产量将会逐渐减少，石化柴油燃烧后所排放的废气是造成的城市空气污染的主要原因，生物柴油是石化柴油很好的替代能源，文章介绍了国外废油脂处理利用和甸餐饮业废油脂的概况，提出了利用餐饮业废油脂制造生物柴油的方法和工艺流程，并讨论了利用餐饮业废油脂制造生物柴油的几个问题。     

信息化机房与网络改造方案设计

工厂信息化总体结构可分为2个网络,1个数据平台,3个层次,可为工厂的高层决策、生产经营管理提供安全可靠的信息化支撑平台,提高企业的综合竞争力,根据实际工程案例详细论述了机房与网络改造方案的设计,对工厂信息化机房的设计具有指导性意义,图1,参3．     

城市公共交通车辆内噪声调查与模糊数学评价

本文以济南市为例，调查了公共交通车辆内噪声随运行路段、时间、车况、路况的变化情况，比较分析表明，发动机是车内主要噪声源，电车和单车内噪声比通道汽车低３ｄＢ－７ｄＢ，一天内噪声变化与市民乘车上下班时间呈正相关，运用模糊数学方法评价得出济南市公共交通车辆内声环境质量为Ⅱ级（７７ｄＢ），并提出了改革车内声环境的对策 。     

城市公共交通车辆内噪声调查与模糊数学评价——以山东省济南市为例

本文以济南市为例，调查了公共交通车辆内噪声随运行路段、时段、车况、路况的变化情况，比较分析表明，发动机是车内主要噪声源，电车和单车内噪声比通道汽车低３ｄＢ～７ｄＢ，一天内噪声变化与市民乘车上下班时间呈正相关。运用模糊数学方法评价得出济南市公共交通车辆内声环境质量为Ⅱ级（７７ｄＢ），并提出了改革车内声环境的对策     

确定噪声超标收费标准因素的探讨

噪声污染已成为城市环境污染的一大公害,实行噪声超标收费是促进噪声源治理的有效措施。本文较详细地分析了我国目前计算噪声超标费的三种主要模式,各具特点,对确定超标收费因素进行了探讨,由此提出了较完善的收费标准。     

城市居住小区交通噪声的空间分布特征

根据实测所得交通流量和车型分布，采用预测为主、实测为辅的方法对典型居住小区进行了交通噪声预测与评价。对小区交通噪声的空间分布作了详细的分析，发现临街住宅交通噪声超标严重。另外，敏感点在建筑物中的朝向和楼层对交通噪声影响较大。上述空间分布规律对小区交通噪声评价与防治具有指导意义。     

上海纸盒十六厂噪声控制设计及效果

上海纸盒十六厂位于市政府拟建安静小区之内,工厂四周与居民住宅毗邻,有的仅一墙之隔。该厂轧盒机车间、切纸间、空压机房、锅炉房等产生的噪声严重污染周围环境,尤其是传至南侧幼儿园的噪声高达72dB(A)。采用隔声、吸声、消声、隔振、通风空调等综合治理措施,使该厂噪声达到了上海市区域环境噪声标准一类混合区的要求,幼儿园噪声降为54dB(A),通过了安静小区验收。     

A comparative study of particle size distribution from two oxygenated fuels and diesel fuel

Oxygenated fuels are known to reduce particulate matter (PM) emissions from diesel engines. In this study, 100% soy methyl ester (SME) biodiesel fuel (B100) and a blend of 10% acetal denoted by A-diesel with diesel fuel were tested as oxygenated fuels. Particle size and number distributions from a diesel engine fueled with oxygenated fuels and base diesel fuel were measured using an Electrical Low Pressure Impactor (ELPI). Measurements were made at ten steady-state operational modes of various loads at two engine speeds. It was found that the geometric mean diameters of particles from SME and Adiesel were lower than that from base diesel fuel. Compared to diesel fuel, SME emitted more ultra-fine particles at rated speed while emitting less ultra-fine particles at maximum speed. Ultra-fine particle number concentrations of A-diesel were much higher than those of base diesel fuel at most test modes.     

燃用甲醇燃料的发动机尾气排放

本文主要报导了在二冲程、四冲程汽油机及柴油机上燃用甲醇-汽油混合燃料、M_(100)甲醇燃料的发动机尾气排放方面所做的研究,并与燃用汽油、柴油的尾气排放进行了对照。结果表明,无论是甲醇-汽油混合燃料,还是M_(100)甲醇燃料尾气排放,都较汽油、柴油尾气排放的常规污染物,均有不同程度的减少。因此,应用甲醇燃料对改善环境是有益的。     

Polynuclear aromatic compounds in kerosene,diesel and unmodified sunflower oil and in respective engine exhaust particulate emissions

Polynuclear aromatic compounds (PAC) were characterized in diesel fuel, kerosene fuel and unmodified sunflower oil as well as in their respective engine exhaust particulates. Diesel fuel was found to contain high amounts of different PAC, up to a total concentration of 14,740?ppm, including carbazole and dibenzothiophene, which are known carcinogens. Kerosene fuel was also found to contain high amounts of different PAC, up to a total concentration of 10,930?ppm, consisting mainly of lower molecular weight (MW) naphthalene and its alkyl derivatives, but no PAC component peaks were detected in the unmodified sunflower oil. Engine exhaust particulates sampled from a modified one-cylinder diesel engine running on diesel, kerosene and unmodified sunflower oil, respectively, were found to contain significantly high concentrations of different PAC, including many of the carcinogenic ones, in the soluble organic fraction (SOF). PAC concentrations detected at the exhaust outlet indicated that most of the PAC that were present in diesel and kerosene fuels before the test runs got completely burnt out during combustion in the engine whereas some new ones were also formed. The difference between the character and composition of PAC present in the fuels and those emitted in the exhaust particulates indicated that exhaust PAC were predominantly combustion generated. High amounts of PAC, up to totals of 52,900 and 4830?µg?m^?3 of burnt fuel, in diesel and kerosene exhaust particulates, respectively, were detected in the dilution tunnel when the exhaust emissions were mixed with atmospheric air. Significant amounts of PAC were also emitted when the engine was run on unmodified sunflower oil with a total concentration of 17,070?µg?m^?3 of burnt fuel detected in the dilution tunnel. High proportions of the combustion-generated PAC determined when the engine was run on diesel, kerosene and unmodified sunflower, respectively, consisted of nitrogen-containing PAC (PANH) and sulphur-containing PAC (PASH).     

平顶山市区道路交通噪声污染现状与防治

对平顶山市区道路交通噪声污染现状进行了调查，分析了市区道路交通噪声产生的原因和污染特点，提出了市区道路交通噪声的有关防治措施。     

绿化带对不同频率城市交通噪声的衰减作用

植物绿化对交通噪声具有一定的阻挡与衰减作用,其衰减效果取决于绿化带的构成、纵深等。研究选取杭州西湖风景区5个绿化带和1个空地区,测量1/3倍频程下交通噪声的衰减情况。结果表明：10 m左右纵深的绿化带可使交通噪声降低3-5 dB;绿化带的降噪效果在中低频要好于高频,最高在315-400 Hz之间;绿化带辅助地形的下降可有效提高降噪效果;绿化带中乔木选用阔叶类植物的降噪量高于针叶类植物3 dB左右,在低频段降噪量的提升要高于中高频段。     

Effects of a diesel oxidation catalyst on gaseous pollutants and fine particles from an engine operating on diesel and biodiesel

The effects of a diesel oxidation catalytic (DOC) converter on diesel engine emissions were investigated on a diesel bench at various loads for two steady-state speeds using diesel fuel and B20. The DOC was very effective in hydrocarbon (HC) and CO oxidation. Approximately 90%–95% reduction in CO and 36%–70% reduction in HC were realized using the DOC. Special attention was focused on the effects of the DOC on elemental carbon (EC) and organic carbon (OC) fractions in fine particles (PM_2.5) emitted from the diesel engine. The carbonaceous compositions of PM_2.5 were analyzed by the method of thermal/optical reflectance (TOR). The results showed that total carbon (TC), OC and EC emissions for PM_2.5 from diesel fuel were generally reduced by the DOC. For diesel fuel, TC emissions decreased 22%–32% after the DOC depending on operating modes. The decrease in TC was attributed to 35%–97% decrease in OC and 3%–65% decrease in EC emissions. At low load, a significant increase in the OC/EC ratio of PM_2.5 was observed after the DOC. The effect of the DOC on the carbonaceous compositions in PM_2.5 from B20 showed different trends compared to diesel fuel. At low load, a slight increase in EC emissions and a significant decrease in OC/EC ratio of PM_2.5 after DOC were observed for B20.     

高速公路与城市道路沿线交通噪声对环境的污染分析

在我国一些中心大城市,道路交通量迅猛增长,交通污染的问题也日益突出。本文主要阐述了交通噪声对道路沿线环境污染的危害,并提出了降噪为主要目标的综合治理的方法以及措施：采用多孔隙低噪声沥青路面,设置声屏障以及在道路两侧设置绿化带降噪声等,     

建筑施工噪声污染现状与防治对策

城区建筑施工噪声主要来源于建筑机构，其产生的噪声一般均超过国家施工临界噪声限值，影响周围居民正常生活和身体健康，为此，提出了相应的防治对策。     

Mutagenicity of diesel engine exhaust in the Ames / Salmonella assay using a direct exposure method

The aim of this study was to investigate the potential mutagenic activity of diesel engine exhaust in the Ames/Salmonella assay using a direct aerosol exposure system. So, TA 98 and TA 100 strains, with or without added S9 mix, were exposed to diesel emissions after varying degrees of filtration. Variants of these two strains, deficient in nitroreductase (TA 98NR and TA 100NR) or over-expressing O-Acetyl Transferase (YG 1024 and YG 1029), were also exposed to total (unfiltered) diesel exhaust to highlight the putative mutagenicity of any nitro-PAHs present in these emissions. Mutagenic activity of the diesel exhaust was demonstrated on Salmonella typhimurium, strains TA 100 and variants TA 100 NR and YG1029. The use of a particle filter did not modify the genotoxicity of the diesel emissions, indicating a major contribution of the gas phase to the mutagenicity of these diesel emissions. The prominent role of the particulate-associated nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) claimed by some authors working on diesel exhaust organic extracts was not confirmed by our results with native diesel exhaust exposure. Our results show that the gas phase is potentially more mutagenic than the particles alone.     

Study of engine performance,emission and combustion characteristics fueled with diesel-like fuel produced from waste engine oil and waste plastics

Utilizing oil extracted from waste engine oil and waste plastics, by pyrolysis, as a fuel for internal combustion engines has been demonstrated to be one of the best available waste management methods. Separate blends of fuel from waste engine oil and waste plastic oil was prepared by mixing with diesel and experimental investigation is conducted to study engine performance, combustion and exhaust emissions. It is observed that carbon monoxide (CO) emission increases by 50% for 50% waste plastic oil (50WPO:50D) and by 58% for 50% waste engine oil (50WEO:50D) at full load as compared to diesel. Unburnt hydrocarbon (HC) emission increases by 16% for 50WPO:50D and by 32% for 50WEO:50D as compared to diesel at maximum load. Smoke is found to decrease at all loading conditions for 50WPO:50D operation, but it is comparatively higher for 50WEO:50D operation. 50WPO:50D operation shows higher brake thermal efficiency for all loads as compared to 50WEO:50D and diesel fuel operation. Exhaust gas temperature is higher at all loads for 50WPO:50D and 50WEO:50D as compared to diesel fuel operation.

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