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排序方式: 共有1340条查询结果,搜索用时 531 毫秒
831.
B. K. Goswami Rajesh Kumar Pandey Jaideep Goswami D. D. Tewari 《Journal of environmental science and health. Part. B》2013,48(8):899-904
This investigation was undertaken to compare the percentage response of colonization and development of VA-Mycorrhiza (Glomus fasciculatum) on a number of pulse crops viz. cowpea, chickpea, soybean, pigeonpea and lentil under glasshouse conditions. Among the above-mentioned crops, pigeonpea exhibited the best performance and was selected for further studies. In this host the development and colonization percentage of G. fasciculatum was investigated under two separate substrates i. e. soil amended with FYM and karanj oilseed cake keeping a control treatment of field soil. A third treatment amended with karanj oilseed cake and farm yard manure (FYM) was also kept which responded best in terms of colonization percentage. This treatment showing improved plant health as well as integration with G. fasciculatum was selected as an ideal treatment for the management of disease complex caused by root knot nematode, Meloidogyne incognita and root wilt fungus, Fusarium udum on pigeonpea. Thus the treatment constituting FYM, karanj oilseed cake and VA-Mycorrhiza reduced the disease incidence caused by both maladies to a great extent with the most promising improvement in plant growth parameters as compared to all others. The present investigation, in addition to proposing an ideal eco-friendly treatment for the management of this disease complex also proposed an excellent medium for the proliferation of the obligate bio-protectant, G. fasciculatum. 相似文献
832.
乌鲁木齐市医院污水处理水平现状分析 总被引:4,自引:0,他引:4
乌鲁木齐地区共有29家大中型医院,建立污水处理设施的共有15家,占51.7%,其中处理后达标排放的占31.6%。从处理方法及效果来看,经一级处理的医院排水,主要监测指标仍有不同程度的超标,采用二级处理的效果则比较显著。为确保2000年达标排放,有关部门应采用相应的措施督促大中型医院尽早用二级处理方法处理其排水。 相似文献
833.
A novel differential pulse voltammetry (DPV) method was developed for the simultaneous analysis of herbicides in water. A mixture of four herbicides, atrazine, simazine, propazine and terbuthylazine was analyzed simultaneously and the complex, overlapping DPV voltammograms were resolved by several chemometrics methods such as partial least squares (PLS), principal component regression (PCR) and principal component–artificial networks (PC–ANN). The complex profiles of the voltammograms collected from a synthetic set of samples were best resolved with the use of the PC–ANN method, and the best predictions of the concentrations of the analytes were obtained with the PC-ANN model (%RPET = 6.1 and average %Recovery = 99.0). The new method was also used for analysis of real samples, and the obtained results were compared well with those from the GC-MS technique. Such conclusions suggest that the novel method is a viable alternative to the other commonly used methods such as GC, HPLC and GC-MS. 相似文献
834.
在水溶液中,以微波辅助无极汞灯(Microwave-Assisted Eletrodeless Discharge Mercury Lamp,MW-EDML)降解氯氰菊酯、甲氰菊酯和功夫菊酯等3种拟除虫菊酯农药(Synthetic pyrethroids,SPs),采用固相萃取(Solid Phase Extraction,SPE)富集后,用GC-MS鉴定降解产物,并根据降解产物重点探讨了SPs的降解机理。3种SPs的主要降解产物有6种,其降解途径有:酯键水解、氰基水解、脱羧、醚键断裂、氧化、苯环的羟基化以及与溶剂反应等。实验结果还表明:MW-EDML是个高效、简便的降解SPs类农药手段,可应用于其他有机污染物的降解过程。 相似文献
835.
836.
水污染物排放总量控制方法研究--以无锡城北地区为例 总被引:1,自引:1,他引:0
水环境已经成为整个苏南地区经济发展的制约因素之一,为实现经济效益与环境效益协调发展,对水污染物排放实行总量控制至关重要。在对无锡城北地区水污染物负荷、水环境现状及水环境功能充分调查的基础上,结合该区域的水文特征和排水规划,统计分析出区域内水污染物的排放总量,根据污水集中处理方案,计算出区域水污染物的削减量,然后运用河网水质模型,预测水污染物削减后河流水质改善状况,以改善后水环境质量为本底值,以下游水环境保护目标的环境功能为控制要求,反推该区域在污水实行集中处理后所能接纳的水污染物排放总量。通过科学计算得知区域水环境纳污能力为19.8 t/d,由此确定的经济规模有限,必将制约地方经济的发展,提出了扩大水环境纳污能力的有效途径,并提出了建设无锡地区污水入江通道的设想。 相似文献
837.
我国在工程设计中越来越多地采用共同沟工艺,但尚未有国家层面的标准化的相关规范,因此现阶段的工艺设计在给排水方面需参照国外及国内已兴建的共同管沟,尽可能全面地考虑工程设计中会碰到的问题,由此提出一些设计理念。 相似文献
838.
839.
铁路危险品货场中人体静电放电隐患的测量与评估 总被引:1,自引:0,他引:1
刘明翔 《中国安全科学学报》2006,16(2):114-119
根据人体静电的基本理论,人体的对地静电电位、电容和电阻是静电放电隐患的3个主要评估参数,也是建立静电危害模型的关键参数。笔者结合实际测量数据,对铁路危险品货场中人体静电放电的隐患进行了分析与评估,并探讨了其危害机理,提出了流动人体模型和人体—老虎车模型,给出了模型参数的数值。基于实测数据和放电模型分析的评估结果表明:在铁路危险品货场中,源于人体静电放电的静电电击和静电引爆两个隐患不容忽视;与基于实测数据的直接评估结果相比,人体—老虎车模型得出的评估结论是静电放电隐患,更值得关注。 相似文献
840.
Hiie Hinrikus Ruth Tomson Jaanus Lass Deniss Karai Jaak Kalda Viiu Tuulik 《The Environmentalist》2005,25(2-4):157-163
Summary This study is aimed to investigate dependence of nerve pulse conduction velocity on low-level microwave exposure. The changes
in fiber membrane permeability or myelin sheath, caused by microwave, should affect nerve pulse conduction velocity. Experimental
investigation was carried out for nerve pulse conduction velocity with and without applied microwave field and different orientations
of its polarization to the nerve fiber. Microwave radiation of 450 MHz was applied polarized perpendicular or parallel to
the nerve fiber. The measured field power density at the skin was 0.87 mW/cm2. Special program was developed for calculation of the nerve pulse conduction velocity in LabView environment. The right nervus
medianus motor nerve fibers of 35 young subjects were under the study. The experimental protocol included ten measurements
in every cycle of five different exposure conditions. No changes in average values of the conduction velocities discovered
in different exposure conditions. Theoretical calculations based on Hodgkin-Huxley model confirm only a weak possible effect.
The results showed that low-level microwave radiation did not cause statistically significant change in nerve pulse conduction
velocity in human motor nerve fiber. 相似文献