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71.
Dissipation and decontamination of chlorantraniliprole (Coragen 18.5 SC) in brinjal and okra fruits were studied following field application at single and double doses of 30 and 60 g ai ha?1, and the residues of the insecticide was estimated using LC-MS/MS. Initial residues of chlorantraniliprole at single and double doses on the fruits of brinjal were 0.72 and 1.48 mg kg?1, while on okra fruits, the residues were 0.48 and 0.91 mg kg?1, respectively. The residues reached below detectable level of 0.01 mg kg?1 on the 10th day. Half-life of chlorantraniliprole at 30 and 60 g ai ha?1 on brinjal was 1.58 and 1.80 days with the calculated waiting period of 0.69 and 2.38 days, whereas on okra, the values were 1.60 and 1.70 and 0 and 1.20 days, respectively. The extent of removal of chlorantraniliprole using simple decontaminating techniques at 2 h and 3 days after spraying was 40.99–91.37 % and 29.85–89.12 %, respectively, from brinjal fruits and 47.78–86.10 % and 41.77–86.48 %, respectively, from okra fruits.  相似文献   
72.
针对依兰县绿色食品种植面积,种植基地建设,养殖基地建设,山产品采集基地建设,加工基地建设和销售基地建设及经济效益情况,提出了目前依兰县绿色食品开发已初步形成的标准体系框架并进行论述,评价分析了依兰县绿色食品产业的有利条件和制约困素,并提出发展的对策,使之逐步走向依兰县农业经济的主导地位.  相似文献   
73.
野生动物资源作为一种可更新资源,与人类生活密切相关。发展经济使生态环境受到很大破坏,并涉及野生动物的生存环境。阐述野生动物资源对人类社会的科学价值,引起人们对野生动物资源的重视,以便更好地保护和管理野生动物资源。  相似文献   
74.
分光光度法测定雨水中微量过氧化氢的研究   总被引:1,自引:0,他引:1  
本文提出了以钛(IV) 过氧化氢 2 (3,5 二溴 2 吡啶偶氮) 5 二乙氨基苯酚(3,5 diBr PADAP)三元配合物体系光度测定雨水中微量过氧化氢的方法,该方法简便,灵敏度和选择性较高,所得结果令人满意  相似文献   
75.
闽南地区生态环境对酸沉降的临界负荷研究   总被引:3,自引:0,他引:3  
报道了闽南生态环境对酸沉降临界负荷的研究结果。考虑到干、湿2种沉降形式,试用了1种新的酸沉降临界负荷计算方法:用树木和农作物的SO2容量代表酸性干沉降的临界负荷,用土壤酸缓冲容量计算酸性湿沉降的临界负荷。结果表明:闽南的干、湿酸沉降临界负荷均大大高于现实酸沉降负荷   相似文献   
76.
等离子体分解SO2实验   总被引:7,自引:0,他引:7  
介绍了在低温常压条件下,应用等离子体分解有害气体SO2的实验结果,通过实验总结出SO2浓度,气体流量以及烟气温度SO2分解率的影响规律,比较了脉冲叠加正、负直流电压产生的等离子体分解SO2的能耗和分解量。实验结果表明,该项技术耗能低,SO2分解率高。每消耗1kW·h电能可分解1.61-1.97kgSO2气体,分解率达80%以上。  相似文献   
77.
多氯酚QSAR数值模型比较研究   总被引:6,自引:0,他引:6  
应用多元线性回归分析和新近发展起来的人工神经网络方法进行了一类重要环境污染物多氯酚的定量构效关系研究,并用所建立的模型进行毒性预报,计算值与实验值的比较表明,前的相关系数约为0.92,后的相关系数约为0.99.后的百分误差地明显小于前,后的预报能力略好于前,中还讨论了后优于前的的原因。  相似文献   
78.
白爱民 《云南环境科学》1996,15(4):27-28,10
YEP采用了先进的计算机管理技术与电子邮件网络系统,到目前为止,省项目办和英国DRA咨询专家与世界银行和涉及YEP的各有关单位之间及时准确地进行了大量的数据传输工作,保证了YEP工作的顺利进行。  相似文献   
79.
The transport behaviors of a suite of contaminants released from electronic waste (e-waste) recycling operations, including polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and heavy metals, were evaluated by analyzing the contaminant residues in surface soils sampled in the surrounding area of an e-waste recycling site in South China. Concentrations of PBDEs and PCBs in the soil samples ranged from 0.565 to 2908 ng g(-1) dw and from 0.267 to 1891 ng g(-1) dw, respectively, while soil residues were 0.082-2.56, 3.22-287, and 16.3-162 μg g(-1) dw for Cd, Cu, and Pb, respectively. Concentrations of PBDEs and PCBs in soil decreased with increasing distance from the source of pollution, indicating possible PBDE and PCB contamination in the surrounding areas due to the short-range transport of these compounds from the e-waste recycling site. Although no significant difference in the short-range transport potential among PBDE and PCB congeners was observed, reductions in concentrations of the highly-brominated-BDEs and highly-chlorinated-CBs were slightly quicker than those of their less-halogen-substituted counterparts. Conversely, heavy metals showed the lowest transport potential due to their low vapor pressure, and results showed metals would remain near the pollution source instead of diffusing into the surrounding areas. Finally, mass inventories in areas near the e-waste site were 0.920, 0.134, 0.860, 4.68, 757, and 673 tons for BDE209, PBDEs (excluding BDE209), PCBs, Cd, Cu, and Pb, respectively.  相似文献   
80.
Inland lakes are major surface water resource in arid regions of Central Asia. The area changes in these lakes have been proved to be the results of regional climate changes and recent human activities. This study aimed at investigating the area variations of the nine major lakes in Central Asia over the last 30 years. Firstly, multi-temporal Landsat imagery in 1975, 1990, 1999, and 2007 were used to delineate lake extents automatically based on Normalized Difference Water Index (NDWI) threshold segmentation, then lake area variations were detailed in three decades and the mechanism of these changes was analyzed with meteorological data and hydrological data. The results indicated that the total surface areas of these nine lakes had decreased from 91,402.06 km2 to 46,049.23 km2 during 1975?C2007, accounting for 49.62% of their original area of 1975. Tail-end lakes in flat areas had shrunk dramatically as they were induced by both climate changes and human impacts, while alpine lakes remained relatively stable due to the small precipitation variations. With different water usage of river outlets, the variations of open lakes were more flexible than those of other two types. According to comprehensive analyses, different types of inland lakes presented different trends of area changes under the background of global warming effects in Central Asia, which showed that the increased human activities had broken the balance of water cycles in this region.  相似文献   
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