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31.
三阶段温度控制堆肥接种法对有机氮变化规律的影响 总被引:1,自引:0,他引:1
利用原生生活垃圾,通过三阶段温度控制技术进行堆肥试验,探讨在堆肥过程中有机态氮组分的动态变化规律.结果表明,全氮、酸水解有机态氮、氨基酸态氮均在堆肥的前期呈明显的下降趋势,呈较好的相关性.与CK(对照组)处理相比,在堆肥的后期,三阶段温度控制堆肥酸水解有机态氮、氨基酸态氮、氨基糖态氮及酸解未知态氮含量呈不同程度的上升趋势,增加幅度依次为:10.67%、16.17%、7.17%、22.44%.表明三阶段温度控制技术能减少堆肥中氮素的损失,堆肥产品施入土壤后,可提高土壤的供氮潜力. 相似文献
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常规监测高锰酸盐指数-酸性法,通过对高锰酸盐指数空白测试与检测限、空白质控图、空白加标回收率进行测试研究,可以得到理想的监测结果。 相似文献
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将桉树叶提取液绿色还原氧化石墨烯(G-rGO)电极和微生物还原氧化石墨烯(B-rGO)电极依次作为微生物燃料电池(MFC)阳极,采用红外光谱(FTIR)、X射线衍射(XRD)、扫描电镜(SEM)对所制备的电极进行表征,并采用循环伏安法(CV)、交流阻抗法(EIS)对比2种电极的电化学性能.结果发现,G-rGO阳极的内阻为243.87Ω,应用于MFC时最大功率密度和最大输出电压分别为18.77 W·m~(-3)和760 mV,对照组B-rGO电极的内阻为299.11Ω,将其应用于MFC时最大功率密度和最大输出电压分别为13.16 W·m~(-3)和635 mV,对照组未修饰阳极的内阻为375.21Ω,最大功率密度和最大输出电压分别为8.97 W·m~(-3)和480 mV.研究表明,G-rGO电极电阻更小,导电性能更优越. 相似文献
36.
利用ADINA中的势流体单元对一已建成的深水高墩建模,桥梁上部结构对桥墩的影响以墩顶集中质量的形式体现,分别对不同水深条件下桥墩-水体系的动力特性和地震动响应进行了系统的求解;为了检验Morison方程在深水桥墩动力分析中的有效性,将基于忽略速度力项的Morison方程的计算结果与基于势流体的结果进行了比较.研究结果表... 相似文献
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Paz-Alberto AM Sigua GC Baui BG Prudente JA 《Environmental science and pollution research international》2007,14(7):498-504
Background, Aims and Scope The global problem concerning contamination of the environment as a consequence of human activities is increasing. Most of
the environmental contaminants are chemical by-products and heavy metals such as lead (Pb). Lead released into the environment
makes its way into the air, soil and water. Lead contributes to a variety of health effects such as decline in mental, cognitive
and physical health of the individual. An alternative way of reducing Pb concentration from the soil is through phytoremediation.
Phytoremediation is an alternative method that uses plants to clean up a contaminated area. The objectives of this study were:
(1) to determine the survival rate and vegetative characteristics of three grass species such as vetivergrass, cogongrass
and carabaograss grown in soils with different Pb levels; and (2) to determine and compare the ability of the three grass
species as potential phytoremediators in terms of Pb accumulation by plants.
Methods The three test plants: vetivergrass (Vetiveria zizanioides L.); cogongrass (Imperata cylindrica L.); and carabaograss (Paspalum conjugatum L.) were grown in individual plastic bags containing soils with 75 mg kg−1 (37.5 kg ha−1) and 150 mg kg−1 (75 kg ha−1) of Pb, respectively. The Pb contents of the test plants and the soil were analyzed before and after experimental treatments
using an atomic absorption spectrophotometer. This study was laid out following a 3 × 2 factorial experiment in a completely
randomized design.
Results On the vegetative characteristics of the test plants, vetivergrass registered the highest whole plant dry matter weight (33.85–39.39
Mg ha−1). Carabaograss had the lowest herbage mass production of 4.12 Mg ha−1 and 5.72 Mg ha−1 from soils added with 75 and 150 mg Pb kg−1, respectively. Vetivergrass also had the highest percent plant survival which meant it best tolerated the Pb contamination
in soils. Vetivergrass registered the highest rate of Pb absorption (10.16 ± 2.81 mg kg−1). This was followed by cogongrass (2.34 ± 0.52 mg kg−1) and carabaograss with a mean Pb level of 0.49 ± 0.56 mg kg−1. Levels of Pb among the three grasses (shoots + roots) did not vary significantly with the amount of Pb added (75 and 150
mg kg−1) to the soil.
Discussion Vetivergrass yielded the highest biomass; it also has the greatest amount of Pb absorbed (roots + shoots). This can be attributed
to the highly extensive root system of vetivergrass with the presence of an enormous amount of root hairs. Extensive root
system denotes more contact to nutrients in soils, therefore more likelihood of nutrient absorption and Pb uptake. The efficiency
of plants as phytoremediators could be correlated with the plants’ total biomass. This implies that the higher the biomass,
the greater the Pb uptake. Plants characteristically exhibit remarkable capacity to absorb what they need and exclude what
they do not need. Some plants utilize exclusion mechanisms, where there is a reduced uptake by the roots or a restricted transport
of the metals from root to shoots. Combination of high metal accumulation and high biomass production results in the most
metal removal from the soil.
Conclusions The present study indicated that vetivergrass possessed many beneficial characteristics to uptake Pb from contaminated soil.
It was the most tolerant and could grow in soil contaminated with high Pb concentration. Cogongrass and carabaograss are also
potential phytoremediators since they can absorb small amount of Pb in soils, although cogongrass is more tolerant to Pb-contaminated
soil compared with carabaograss. The important implication of our findings is that vetivergrass can be used for phytoextraction
on sites contaminated with high levels of heavy metals; particularly Pb.
Recommendations and Perspectives High levels of Pb in localized areas are still a concern especially in urban areas with high levels of traffic, near Pb smelters,
battery plants, or industrial facilities that burn fuel ending up in water and soils. The grasses used in the study, and particularly
vetivergrass, can be used to phytoremediate urban soil with various contaminations by planting these grasses in lawns and
public parks.
ESS-Submission Editor: Dr. Willie Peijnenburg (wjgm.peijnenburg@rivm.nl) 相似文献
39.
小麦在与水杨酸诱导的应答过程中PGIP的积累 总被引:7,自引:1,他引:6
以SW89-2589小麦品系为材料,利用自制的小麦抗PGIP血清和dot-immunobinding assay,并结合PGIP粗提液对endo-PG的抑制实验,研究了小麦内源多聚半乳糖醛酸酶抑制蛋白(PGIP)水平与水杨酸之间的应答关系。发现用水杨酸处理过的PGIP粗提液在NC膜上的显色斑点颜色均较H2O处理的PGIP粗提液深,而且对en-do-PG的抑制程度也高于未用水杨酸处理的PGIP粗提液 相似文献
40.
Result-oriented approaches to the management of drinking water catchments in agricultural landscapes
Alexander Wezel Maria Zipfer Christine Aubry Fabienne Barataud Alois Heißenhuber 《Journal of Environmental Planning and Management》2016,59(2):183-202
Management of water quality in drinking water catchments is of ongoing, high importance as nitrate concentrations are often still very high. We analysed the Augsburg catchment in Germany, a unique example where a result-oriented approach has been implemented. We investigated the historical evolution of the water protection programme, the result-oriented payment contracts with farmers, and farmer satisfaction with the contracts, based on interviews with the water utility and farmers as well as an analysis of the literature. Today, the water protection programme has been successfully implemented, and a significant reduction of nitrate concentration was achieved due to the following factors: (1) investment of non-negligible amounts of money for high compensation and remuneration payments, (2) different contract options, (3) farmers’ participation in the negotiation process for result-oriented payment contracts, (4) involvement of “outside” people and institutions in negotiation processes, (5) anticipation of starting a programme when nitrate levels were still far below legislative thresholds, and (6) a political and legislative framework allowing direct decisions by a water supplier. 相似文献