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191.
植物修复--大面积低剂量放射性污染的新治理技术   总被引:5,自引:0,他引:5  
放射性污染是当今难以治理的环境污染问题,对于大面积低剂量的放射性污染,植物修复是种较适用的新型治理技术.系统阐述了植物修复技术的概念与内容,对放射性污染植物修复技术研究现状与进展、植物修复的优缺点进行了重点评述,并对这技术在未来放射性污染治理中的应用与研究提出了建议.  相似文献   
192.
土壤生物的学习行为是一种综合性的神经高级活动,对土壤中的神经毒性污染物生态风险监测具有重要价值.本研究设计了一套试验装置,基于蚯蚓对白光刺激的厌恶本性,通过振动-白光配对刺激,对蚯蚓进行学习训练,使蚯蚓领会借助加速移动阻止白光刺激的策略,通过蚯蚓到达移动位移阈值的时间测定,对蚯蚓的学习行为进行测试,建立了蚯蚓的学习行为...  相似文献   
193.
An intensive investigation was conducted to study the distribution of polycyclic aromatic hydrocarbons (PAHs), to show firstly the level of pollution in the agricultural areas and analyses specifically the status of soil polluted by these persistent pollutants in some locations of Xiamen region. Soil samples collected from Jiulong agricultural catchment have been analysed for 16 PAH compounds, using gas chromatography flame ionization detection in order to determine the level of selected PAH components and to identify the factors that may control their distribution and persistence in the area. The main PAHs found in soil samples were the low molecular weight. The total PAHs detected in soil samples ranged from 0.50 to 0.95 μg/g soil. The highest values of PAHs were significantly detected in the orange tree leaves, which range from 236.1 to 249.3 μg/g soil showing recent atmospheric inputs of these volatile pollutants. The distribution of PAHs in vegetable were monitored and indicating that the concentration were high and ranged from 8.24 to 58.87 μg/g. Other sediment samples were also collected and analysed from urban sewage (5.26 μg/g dw), aquacultural (0.52 μg/g dw) and industrial areas (from 0.62 to 2.09 μg/g dw), during this investigation. The contamination of Jiulong river estuary and Xiamen Western Sea by PAHs has been then widely justified by wastcwatcr discharges and soil runoffs from these areas. The results, therefore, provide important information on the current contamination status caused by the atmospheric transport and point to the need for urgent actions to stop the release of these hydrocarbons to the environment. The necessity of implementing systematic monitoring of PAHs is also emphasized.  相似文献   
194.
Removal of heavy metals from a contaminated soil using tartaric acid   总被引:9,自引:0,他引:9  
This study reports the feasibility of remediation of a heavy metal (HM) contaminated soil using tartaric acid, an environmentally-friendly extractant. Batch experiments were performed to test the factors influencing remediation of the HM contaminated soil. An empirical model was employed to describe the kinetics of riM dissolution/desorption and to predict equilibrium concentrations of HMs in soil leachate. The changes of HMs in different fractions before and after tartaric acid treatment were also investigated. Tartaric acid solution containing HMs was regenerated by chestnut shells. Results show that utilization of tartaric acid was effective for removal of riMs from the contaminated soil, attaining 50%-60% of Cd, 40%-50% of Pb, 40%-50% of Cu and 20%-30% of Zn in the pH range of 3.5-4.0 within 24 h. Mass transfer coefficients for cadmium (Cd) and lead (Pb) were much higher than those for copper (Cu) and zinc (Zn). Sequential fractionations of treated and untreated soil samples showed that tartaric acid was effective in removing the exchangeable, carbonate fractions of Cd, Zn and Cu from the contaminated soil. The contents of Pb and Cu in Fe-Mn oxide fraciton were also significantly decreased by tartaric acid treatment. One hundred milliliters of tartaric acid solution containing HMs could be regenerated by 10 g chestnut shells in a batch reactor. Such a remediation procedure indicated that tartaric acid is a promising agent for remediation of HM contaminated soils. However, further research is needed before the method can be practically used for in situ remediation of contaminated sites.  相似文献   
195.
Soil properties, microbial communities and enzyme activities were studied in soil amended with replicase (RP)-transgenic or non-transgenic papaya under field conditions. Compared with non-transgenic papaya, significant differences (P〈0.05) were observed in total nitrogen in soils grown with transgenic papaya. There were also significant differences (P〈0.05) in the total number of colony forming units (CFUs) of bacteria, actinomycetes and fungi between soils amended with RP-transgenic plants and non-transgenic plants. Compared with non-transgenic papaya, the total CFUs of bacteria, actinomycetes and fungi in soil with transgenic papaya increased by 0.43-1.1, 0.21-0.80 and 0.46-0.73 times respectively. Significantly higher (P〈0.05) CFUs of bacteria, actinomycetes and fungi resistant to kanamycin (Km) were obtained in soils with RP-transgenic papaya than those with non-transgenic papaya in all concentrations of Km. Higher resistance quotients for Km' (kanamycin resistant) bacteria, actinomycetes and fungi were found in soil planted with RP-transgenic papaya, and the resistance quotients for Km' bacteria, actinomycetes and fungi in soils with transgenic papaya increased 1.6-4.46, 0.63-2.5 and 0.75-2.30 times. RP-transgenic papaya and non-transgenic papaya produced significantly different enzyme activities in arylsulfatase (5.4-5.9x), polyphenol oxidase (0.7-1.4x), invertase (0.5-0.79x), cellulase (0.23-0.35x) and phosphodiesterase (0.16-0.2x). The former three soil enzymes appeared to be more sensitive to the transgenic papaya than the others, and could be useful parameters in assessing the effects of transgenic papaya. Transgenic papaya could alter soil chemical properties, enzyme activities and microbial communities.  相似文献   
196.
Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the present study, laboratory batch experiment of metal solubilization, cress seeds germination were undertaken to investigate the metal-mobilizing capability and the phytotoxicity of organic additives, including ethylene diamine triacetic acid (EDTA), citric acid, acetic acid, oxalic acid, glutamine and monosodium glutamate waste liquid (MGWL) from food industry. Experiments in pots were carried out to study the effects of the additives on Zn and Cd phytoextraction. Furthermore, a leaching experiment with lysimeter was performed to evaluate the environmental risks of additive-induced leaching to underground water. The results showed that EDTA had a strong mobilizing ability for Zn and Cd, followed by mixed reagent (MR) and MGWL. MGWL and acetic acid at 5 mmol equivalent per liter resulted in seed germination index less than 2%. Experiments in pots verified the phytotoxicity of acetic acid and MGWL. Addition of the mixed reagent at 6--10 mmol/kg significantly increased Zn phytoextraction by Thlaspi caerulescens. The same for EDTA and the mixed reagent at 10 mmol/kg by Sedum dfredii. But only mixed reagents could significantly increase Cd phytoextraction by the studied hyperaccumulators. This suggested that the strong chelant was not always the good agent to enhance phytoextraction. S. alfredii combined with 2--10 mmol/kg soil MR was preferred for phytoremediation of Cd/Zn contaminated soils in southern China, this could result in high phytoextraction of Cd/Zn and reduce the leaching risk to underground water than EDTA assisted phytoextration.  相似文献   
197.
为从根本上降低煤矿从业人员实施不安全行为的概率,在充分考虑煤矿从业人员不安全个体状态是诱发其不安全行为的主要原因的基础上,设计开发一套矿工不安全状态智能检测系统。首先,对2007—2022年期间各高危行业安全事故调查报告和专家研究进行归纳,总结得出煤矿从业人员不安全状态的影响因素,构建包括生理状态、心理状态以及个体能力状态在内的3个一级指标和15个二级指标体系;其次,通过相应的表征模型对不安全状态影响因素进行深入剖析;最后,基于构建的从业人员不安全状态倾向数据库,建立煤矿岗前不安全状态智能检测系统。研究结果表明:在下井工作前对从业人员个体状态进行智能检测,能够实现矿工不安全状态“早发现、早干预”,能够有效地降低人因事故发生率,研究结果对煤炭行业安全管理具有重要的参考价值。  相似文献   
198.
城市或沿江化工企业污染带来的影响日益突出,对此类化工企业实行搬迁行动,是目前城市或区域实施环境保护的一个重要手段。做好化工搬迁遗留场地土壤污染调查,及时掌握化工搬迁遗留场地的土壤污染状况,可为此类场地搬迁或再开发利用提供技术支撑。以湖北省某农药厂为例,采用资料审阅、人员访谈、现场踏勘等方式开展该工厂的场地环境摸底调查与评估工作,评价场地的土壤污染状况。结果表明:工厂生产区域的土壤和地下水已受到了历史生产活动的影响,污染物质包括重金属、挥发性有机物、半挥发性有机物、石油烃和有机农药类。  相似文献   
199.
根据《中华人民共和国土壤污染防治法》规定“用途变更为住宅、公共管理与公共服务用地的,变更前应当按照规定进行土壤污染状况调查。”本次以山西省朔州市山阴县万同瑞商住楼项目地块研究对象,开展土壤污染状况初步调查工作,在进行现场踏勘、周边企业及地块利用历史调查等工作基础上,对地块内可能存在的污染物进行全面识别,明确地块土壤和地下水中污染物类型、污染程度和污染范围,为地块的开发利用提供决策支撑。  相似文献   
200.
为进一步探索数据挖据技术在组织事故预防工作中的融入性与适用性,基于24Model构建事故预控基础模型,通过预测准确率数值及接受者操作特性曲线(ROC曲线)对比分析随机森林(RF)、支持向量机(SVM)、决策树(DT)与神经网络(NN)4种方法对组织事故防控效果的预测性能。结果表明:针对事故率控制(Y1)、职业危害预防(Y2)、财产损失3类预测目标(Y3),RF方法均能达到较高的准确率及稳定性,具有较优的预测性能。根据特征重要度(FI)排序,明确对组织事故水平影响最显著的因素为安全实践活动认知(SC5)及安全管理程序文件(SMS3),FI值均大于0.150 0。研究结果可为有效预测组织事故防控效果提供方法依据,同时为企业安全工作的规划设计提供思路。  相似文献   
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