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1.
绿化带对交通噪声的衰减及对主观反应的影响   总被引:6,自引:0,他引:6  
通过不同车辆流模型下道路旁绿化带对交通噪声衰减的计算及模拟,研究了城市道路边绿化带对交通噪声的衰减,并用实测对计算和模拟结果进行了检验。还通过主观反应调查并运用模糊隶属度原理进行分析计算,论证了绿化带对交通噪声引起的烦恼度心理影响有一定改善。并通过实验数据论证了这一改善在数量上约与绿化带对交通声的实际衰减相当。  相似文献   

2.
通过对置于住宅楼底层室内箱式变压器引起的结构声污染进行调查实测,在对箱式变压器结构声传播进行声学分析基础上,提出了切实可行的防治对策,经实际工程应用验证,效果较好。对机房正上方住房主卧内降噪量为5.0dB,室内夜间噪声降为30.2dB,各层住户夜间烦恼度普遍从非常烦恼或烦恼降为有点烦恼和不大烦恼。这从噪声污染控制的角度证明了变配电房置于住宅楼等噪声敏感建筑物室内底层甚至更高楼层在技术上是可行性的。同时也为杭州市正在试点推广的箱式变压器置于噪声敏感建筑物底层提供了实践依据。  相似文献   

3.
光化学氧化技术去除水中有机污染物的试验研究   总被引:25,自引:0,他引:25  
以自来水为试验对象,对紫外-臭氧和紫外-二氧化钛两种光化学氧化技术对水中微量有机污染物的去除进行了试验研究,结果表明两种工艺的UVA(紫外吸光度)去除率均达到80%以上,对氯仿的去除也均能达到国家饮用水标准。在此基础上,自制了一种催化剂膜,并取得了预期的处理效果,有望在新型净水技术及设备的研制和开发上得到应用。  相似文献   

4.
在实验室和现场对电厂柠檬酸酸洗废水进行生石灰前处理和后续可拆卸式三级矿化垃圾生物反应床的生物处理,主要研究了以往采用矿化垃圾反应床处理废水未涉及的反应床级数对废水处理效果的影响,比较了现场试验和实验室试验中的废水处理效果,并探讨了其原因。试验结果表明,本研究中的矿化垃圾反应床的适宜级数为3,第一级反应床的贡献最大,无论是实验室试验还是现场试验,采用本法处理电厂柠檬酸酸洗废水,均可使废水COD达到一级排放标准。  相似文献   

5.
采用混凝沉淀-厌氧折流板反应池-两极好氧生化工艺处理毛毯废水。在废水pH为4.63-6.95、CODcr为966-1990mg/L、BOD5243-497mg/L、SS焚344-436mg/L、色度400倍时,处理出水达到一级排放标准。该处理技术先进、可靠。  相似文献   

6.
三维电极法在微污染水处理中的应用研究   总被引:6,自引:0,他引:6  
采用三维电极法对微污染水进行处理。试验结果表明,在三维电极反应器中进行的反应为一级反应,反应遵从下述关系:Ct=C0e^-kt;处理效果由水质状况和反应器条件决定;采用绝缘物质与吸附剂按一定比例混合的填料进行处理,能够提高电解效率。  相似文献   

7.
低COD/N—NH4比废水的同时硝化反硝化生物处理策略   总被引:45,自引:0,他引:45  
从生化反应计量学出发,提出了对低COD/N-NH4比废水可以通过控制营养配比,调控溶解氧浓度和控制生物硝化及生物反硝化,经过NO^-2途径进行同时硝化反硝化的生物处理策略。对香港低COD/N-NH4比的垃圾渗漏水用时硝化反硝化处理的成功进行了讨论。  相似文献   

8.
通过咨询有关专家,并采用模糊贴近度方法,对专家意见进行统计处理、归纳和综合,建立了小草浆厂蒸煮废液治理工程实践效果评价的指标体系,从而为小草浆厂蒸煮废液治理工程实践效果的综合评价打下了重要基础。  相似文献   

9.
小型纸厂黑液处理研究   总被引:2,自引:0,他引:2  
论述了采用化学絮凝-炉渣吸附处理小型纸厂黑液的研究。先用絮凝剂处理黑液,处理水再经炉渣吸附过滤,分析处理前后水质的变化,并对炉渣的吸附性能进行选择实验,确定最佳操作条件。结果表明,该法能有效地降低废液中的COD和色度,既经济,又简单,且效果明显,是一种处理黑液的好方法,值得进一步研究。  相似文献   

10.
在含油污泥进行资源化处理过程中,针对处理目标受多个因素影响的实际,为了解决工艺之间的耦合问题,采用正交实验的方法来解决,并把主要参数作为优化对象,把含油污泥的脱水率作为评价目标,通过采用GA-BP算法对含油污泥耦合工艺正交实验参数进行了线性与非线性分析.在采用遗传算法优化神经网络的权值和阈值的基础上,用优化后的权值和阈值对测试样本和训练样本进行了预测.预测结果表明,预测误差都有明显减小,分别由0.34211减少到0.031549和0.15476减少到0.040682,可见耦合参数趋向于非线性优化.  相似文献   

11.
Although in most cases annoying atmospheric emissions do not menace public health, they are less and less tolerated because of the effects on quality of life. Several approaches have been proposed to face this problem but none of them offers a completely satisfying solution. The development of electronic noses, which promise to mimic human sense of smell by means of a sensor array and a pattern recognition model, offers new interesting perspectives. In this paper, an electronic nose based on conducting polymer sensors and a fuzzy logic-based pattern recognition system is tested with waste water samples, obtaining 87% recognition rate on the test set. Current limits of this new technology are discussed and a strategy for their overcoming is proposed.  相似文献   

12.
模糊综合评价在天然水体水质评价中的应用研究   总被引:14,自引:0,他引:14  
采用模糊数学方法,对河网地区面源污染影响较大的代表性河流的水质状况进行综合评价研究。根据监测断面水质污染特点,确定了8个指标作为评价因子,建立了评价因素矩阵,计算出影响因子的权重。在此基础上,提出了模糊综合评价的水质级别,证明该河网地区的污染物主要是氮、磷和有机物。  相似文献   

13.
不同模糊评价方法在水环境质量评价中的应用比较   总被引:7,自引:0,他引:7  
近年来,运用模糊评价方法对水质和水体营养化程度进行评价逐渐受到重视。目前,对模糊评价方法的研究多集中在实测数据标准化、权重的确定和模糊模式识别模型研究几个方面。以滇池历年营养物质数据为实测数据,通过对几种实测数据标准化方法、权重确定方法和模糊模式识别方法的组合应用,获得水环境质量模糊评价最优组合方法。结果表明,在评价方法中,实测数据标准化方法采用线性内插法,权重的确定采用超标倍数法,模糊模式识别模型采用广义海明距离和加权海明距离法,即采用超标倍数法的广义海明距离和加权海明距离法能够更真实反映水环境质量的实际情况。  相似文献   

14.
基于GIS城市道路交通噪声环境管理系统的构架与实现   总被引:3,自引:0,他引:3  
详细介绍了基于GIS技术开发城市道路交通噪声环境管理系统的构架与实现.该系统的开发工作主要包括:噪声数据库设计、噪声数据管理、交通噪声的模拟和交通噪声影响统计.系统采用了数据库技术、GIS技术和交通噪声预测模型,综合考虑实际情况,对城市噪声环境进行管理和模拟.从实例结果分析可见,模拟结果能达到实际使用的要求.该系统能为城市规划、城市环境评价提供信息和技术支持.  相似文献   

15.
在污泥处置策略中,污泥碱式干化被认同是一种安全可靠的处置方式。而我国由于大多采用较为原始的推送装置,不仅石灰消耗量大,而且污泥稳定化效果差,难以实现污泥性状的改善。利用自主研发的高效混合器,在脱水污泥中添加质量分数为5%、7%、10%、12%和15%的500目工业石灰后,分别测定添加后污泥的温度、pH、粪大肠菌值以及臭味强度的变化,并采用模糊数学法评价了添加不同比例的石灰对污泥的稳定化效果,结果表明:添加不同比例的工业用生石灰后,污泥的温度从原污泥的30℃分别升高到32.0、36.0、39.2、41.0和43.3℃;污泥中的pH从原污泥的6.5左右均升高到12以上;粪大肠菌值从原污泥的1.08×10-8 g/MPN均降为0.01 g/MPN以下;臭味强度从5级降为2级以下;污泥稳定化程度高,模糊综合评价结果都为一级。因此,添加5%的石灰即可实现污泥的稳定化。  相似文献   

16.
Chemical and microbial methods are the main remediation technologies for chromium-contaminated soil. These technologies have progressed rapidly in recent years; however, there is still a lack of methods for evaluating the chemical and biological quality of soil after different remediation technologies have been applied. In this paper, microbial remediation with indigenous bacteria and chemical remediation with ferrous sulphate were used for the remediation of soils contaminated with Cr(VI) at two levels (80 and 1,276 mg kg?1) through a column leaching experiment. After microbial remediation with indigenous bacteria, the average concentration of water-soluble Cr(VI) in the soils was reduced to less than 5.0 mg kg?1. Soil quality was evaluated based on 11 soil properties and the fuzzy comprehensive assessment method, including fuzzy mathematics and correlative analysis. The chemical fertility quality index was improved by one grade using microbial remediation with indigenous bacteria, and the biological fertility quality index increased by at least a factor of 6. Chemical remediation with ferrous sulphate, however, resulted in lower levels of available phosphorus, dehydrogenase, catalase and polyphenol oxidase. The result showed that microbial remediation with indigenous bacteria was more effective for remedying Cr(VI)-contaminated soils with high pH value than chemical remediation with ferrous sulphate. In addition, the fuzzy comprehensive evaluation method was proven to be a useful tool for monitoring the quality change in chromium-contaminated soils.  相似文献   

17.
One of the most annoying aspects of photochemical air pollution, particularly in the Southern California Air Basin, has been eye irritation. The most aggravating combination of driving in heavy traffic in Los Angeles, suffering from tearing and burning of the eyes together with very limited visibility, was a strong motivation for the public to demand that effective control actions be taken.  相似文献   

18.
In case of large data matrices comparative evaluations of objects/regions with the technique of Hasse diagrams may be troublesome due to a messy system of lines in the graphical representation. Here fuzzy clustering leads to useful simplifications because regions with slightly different pollution pattern are grouped together. However, fuzzy clustering implies to introduce a threshold value for the membership of an object to a cluster and to select the best number of clusters. Therefore many arbitrarities evolve. Within the systematic study presented here we found that some objects are very stable against variations of the threshold value and the number of cluster whereas other objects behaves different. According to their behaviour we investigated a classification of the objects. Formal Concept Analysis shows that in some cases specific pollution pattern imply the membership to one of these classes. For example objects which are characterized by high Pb-, Zn-concentration and moderate S-concentration imply a high stability against variants of the clustering process. Further implications are described in the paper.  相似文献   

19.
运用模糊层次分析法优选制浆造纸废水深度处理方案   总被引:1,自引:0,他引:1  
制浆造纸废水最适深度处理方案的选择是一个多准则决策问题,本文通过建立评价指标体系,从经济费用、技术性能、管理效果和社会效益4个方面,对混凝沉淀(气浮)+过滤、Fenton氧化和生态法3种深度处理方案进行分析;采用层次分析法确定指标体系权重,其中技术性能(0.5333)权重最高;结合模糊数学法开展综合评判,评估各方案的优缺点,最后通过方案总排序确定工程优选方案。同时,针对2个具有代表意义的制浆造纸企业废水深度处理工程案例,在方案隶属度的确定时增加了决策者的期望值和企业的实际情况,分别选取了最适的制浆造纸废水深度处理方案:混凝沉淀(气浮)+过滤法(A企业)和生态法(B企业),这样可以更客观地指导决策者选取最合适的制浆造纸废水深度处理方案。  相似文献   

20.
Noise is a major source of pollution that can affect the human physiology and living environment. According to the World Health Organization (WHO), an exposure for longer than 24 hours to noise levels above 70 dB(A) may damage human hearing sensitivity, induce adverse health effects, and cause anxiety to residents nearby roadways. Pavement type with different roughness is one of the associated sources that may contribute to in-vehicle noise. Most previous studies have focused on the impact of pavement type on the surrounding acoustic environment of roadways, and given little attention to in-vehicle noise levels. This paper explores the impacts of different pavement types on in-vehicle noise levels and the associated adverse health effects. An old concrete pavement and a pavement with a thin asphalt overlay were chosen as the test beds. The in-vehicle noise caused by the asphalt and concrete pavements were measured, as well as the drivers’ corresponding heart rates and reported riding comfort. Results show that the overall in-vehicle sound levels are higher than 70 dB(A) even at midnight. The newly overlaid asphalt pavement reduced in-vehicle noise at a driving speed of 96.5 km/hr by approximately 6 dB(A). Further, on the concrete pavement with higher roughness, driver heart rates were significantly higher than on the asphalt pavement. Drivers reported feeling more comfortable when driving on asphalt than on concrete pavement. Further tests on more drivers with different demographic characteristics, along highways with complicated configurations, and an examination of more factors contributing to in-vehicle noise are recommended, in addition to measuring additional physical symptoms of both drivers and passengers.Implications: While there have been many previous noise-related studies, few have addressed in-vehicle noise. Most studies have focused on the noise that residents have complained about, such as neighborhood traffic noise. As yet, there have been no complaints by drivers that their own in-vehicle noise is too loud. Nevertheless, it is a fact that in-vehicle noise can also result in adverse health effects if it exceeds 85 dB(A). Results of this study show that in-vehicle noise was strongly associated with pavement type and roughness; also, driver heart rate patterns presented statistically significant differences on different types of pavement with different roughness.  相似文献   

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