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1.
通过洗脱实验评价了工业废弃物赤泥、矿井废水对二氧化硫(SO2)的吸收能力,并将两者联合制成脱硫剂.实验结果表明,对于SO2含量为20000 mg·m-3的模拟烟气,当赤泥-矿井废水脱硫剂中固体投加浓度从0 mg·L-1提高到800 mg·L-1时,其对SO2的吸收量从372 mg·L-1提高到978 mg·L-1.矿井废水与赤泥的联合使用具有较高的脱硫效率,较低的脱硫成本,可实现以废治废的目的.  相似文献   

2.
烟气脱硫菌株的筛选与烟气脱硫效率的影响因素   总被引:2,自引:0,他引:2  
为了寻找烟道气中SO2的微生物转化方法,为微生物脱硫技术的工业化应用提供一定的技术依据,进行了烟气脱硫菌株的筛选和影响烟气脱硫效率有关因素的实验研究,结果表明,单一菌株中,5-2-1菌株的脱硫效率最高.培养12 d后,脱硫率达67.20%,与单一菌株相比,混合菌株有更好的脱硫能力;重金属、有机物、氟化物质对菌株脱硫能力的影响结果表明,在菌液中添加Fe3 、Mn2 不仅能促进菌株生长,还能提高生物菌株的脱硫能力;通过正交实验得出,影响生物菌株脱硫能力大小的因素顺序为:Fe3 >Mn2 >联苯>SO2 浓度>Cr3 >pb2 >pH,通过F显著性检验得知,Fe3 、Mn2、联苯的作用是显著的.  相似文献   

3.
生物氧化再生脱硫液的影响因素研究   总被引:1,自引:0,他引:1  
化学-生物法脱硫中使用的脱硫液一般采用生物法氧化再生.探讨了pH、初始Fe3 浓度、硫磺、硫酸钠浓度等因素对生物氧化再生Fe3 的影响.结果表明,生物氧化再生脱硫液的最适初始pH为1.8;Fe3 对细菌生长有抑制作用,初始浓度低于1.5gL-1时对细菌抑制作用较小;硫磺的存在对Fe2 的生物氧化有很大的影响,当硫磺浓度低于2gL-1时,对细菌的影响较小;硫酸钠浓度低于15gL-1时,对生物氧化Fe2 几乎没有影响,通过驯化后,细菌可以耐受更高的硫酸钠浓度.图4表3参10  相似文献   

4.
一步法烟气浸锰-脱硫的工艺参数及机理   总被引:1,自引:1,他引:0  
应用一步法烟气浸锰-脱硫的新工艺,考察烟气流量、烟气SO2浓度、吸收时间、液固比及浸出时间等工艺参数对烟气氧化脱硫效果的影响,并运用溶液化学原理,对SO2及Mn2 在溶液中的组分进行了计算,研究Mn2 液相催化氧化烟气脱硫的机理.在吸收液pH值5-6时,锰主要以Mn2 形态存在,Mn2 的存在强化了从HSO-3开始发生的SO2氧化反应.采用菱锰矿为原料,能有效地脱除含SO2烟气中的硫,在实现烟气脱硫的同时自动调节溶液的pH值,并可从浸出液中回收高价值的硫酸锰.在最佳的工艺条件下,仅一步吸收过程,取得了锰浸出率85%,含SO2烟气脱硫率70%以上的效果.  相似文献   

5.
采用人工配制的高硫酸盐有机废水模拟青霉素废水,研究其经过EGSB反应器厌氧处理后的出水,在厌氧条件下采用生物法将其转化为单质硫的脱硫工艺.当保持S2-/NO3-在1.7—1.8时,S2-保持高去除率且不会进一步生成硫酸盐.脱硫反应器与EGSB反应器联合运行,处理系统运行参数为:进水COD浓度为6000 mg·L-1,硫...  相似文献   

6.
韩粉女  钟秦 《环境化学》2012,31(4):533-538
采用MnO2/H2SO4溶液作为吸收液,以Fe3+作为催化剂在自制的鼓泡反应器内,对模拟烟气进行同时脱硫脱硝的实验研究,主要考察MnO2浓度、Fe3+浓度、pH值、反应温度、NO浓度、SO2浓度、氧含量、烟气流量等因素对SO2和NO脱除效率的影响.实验结果表明,MnO2浓度、Fe3+浓度、烟气流量、反应温度、NO浓度、SO2浓度对脱硝率影响显著,pH值、氧含量对脱硝率影响不大.在整个实验范围内脱硫效率总是保持在98%以上,脱硝效率最高达到70.9%.  相似文献   

7.
德氏假单胞R-8菌脱硫的“硫饥饿”诱导机理   总被引:1,自引:0,他引:1  
以专一性脱硫菌德氏假单胞菌(Pseudomonas delafieldii)R-8为出发菌株,构建了含有重组质粒pRT-D的重组菌株R-8-D.在不同硫酸盐浓度条件下,研究了R-8和R-8-D脱硫的"硫饥饿"诱导机理.结果表明,在充足的Na2SO4(>0.023 mmol L-1)条件下,R-8菌首先利用硫酸盐生长,脱硫酶的合成受阻遏,DBT不被利用,而R-8菌处于"硫饥饿"状态(Na2SO4浓度≤0.023 mmol L-1)时,诱导了脱硫酶的合成,能利用DBT生长;Na2SO4在临界浓度以上时,R-8-D菌阻遏了脱硫基因的报告基因lacZ的表达,低于临界浓度时不抑制lacZ表达.本实验结果从细胞和分子水平上证实了R-8菌脱硫属"硫饥饿"诱导类型,并首次确定了脱硫微生物"硫饥饿"诱导的硫酸盐临界浓度为0.023 mmol L-1,为构建高活性的、不受硫酸盐抑制的脱硫工程菌提供了理论依据和技术支持.图10表1参14  相似文献   

8.
提出了一种有机胺吸收二氧化硫的烟气脱硫工艺.采用填充柱常压吸收常压再生操作流程,以解吸率和有效吸收SO2容量为评价指标,研究了哌嗪水溶液的脱硫性能,并将其与甲基二乙醇胺(MDEA)和乙二胺(EA)溶液作了比较.实验表明,0.3-0.5m01.1-1的哌嗪水溶液在30℃的温度下能达到较佳的吸收效果,而在85℃的温度下解吸能有效地减少富液挥发损失并达到95%以上的解吸率.哌嗪水溶液的单位有效脱硫容量达到了3.49g·g-1,远高于MDEA和EA.  相似文献   

9.
以黄花菜根为试材,研究不同浓度水浸提液对不同品种大白菜种子萌发和幼苗生长的影响,对黄花菜根化感物质的作用进行研究.试验结果表明:不同浓度黄花菜根水浸提液对不同品种大白菜(精选83-1和迷你黄)种子萌发和幼苗生长的作用效果不同.当浓度为10 mg/m L,15 mg/m L,20 mg/m L时,对于精选83-1和迷你黄的化感作用不同,有的表现为促进作用,有的表现抑制作用.高浓度(25 mg/m L)对于精选83-1和迷你黄则全部表现为抑制作用,且浓度越高抑制作用越明显.图5,表2,参12.  相似文献   

10.
UASB反应器处理COD/SO4^2—=0.5有机废水试验   总被引:1,自引:0,他引:1  
本文对使用UASB反应器处理COD/SO42-=0.5有机废水(温度为35±1℃)进行了较系统的研究。试验结果表明:(1)UASB反应器可以较好地处理COD/SO42-=0.5的有机废水,COD去除负荷与SO42-去除负荷之比(ΔCOD/ΔSO42-)在1.0左右。当COD和SO42-的进水负荷分别为1.036g/L/d和2.086g/L/d时,其去除率可达70%和30%以上;而当COD和SO42-的进水负荷分别为2.489g/L/d和4.977g/L/d时,去除率仍可达50%和30%。(2)反应器中的细菌主要是硫酸盐还原菌和发酵性细菌,而产甲烷菌含量很少。(3)反应器中硫化物的抑制浓度为300mg/L,相应的硫化氢浓度为129mg/L。  相似文献   

11.
A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.  相似文献   

12.
Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.  相似文献   

13.
Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.  相似文献   

14.
Summary The adaptation of defensive secretions to their target organisms was examined for the abdominal gland secretions ofBledius furcatus, B. spectabilis andB. arenarius. Therefore the target organisms of the secretion of theseBledius species (i.e. their predators) had to be identified. At the collection sites examined these were the earwigLabidura riparia, the antCataglyphis bicolor, the flyLispe candicans, different carabids of the generaPogonus, Dichirotrichus, Dyschirius, Bembidion andCalathus and the wading birdsHaematopus ostralegus andCalidris alba. The secretion of the abdominal glands contains the toxin ptoluquinone dissolved in either-dodecalactone and 1-undecene (B. furcatus andB. spectabilis) or in octanoic acid and octyloctanoate (B. arenarius). The ratio of these solvents is species-specific. Application experiments using some of the natural insect predators (L. riparia, C. bicolor, Pogonus, Di. gustavii, Dyschirius) revealed that these solvent ratios provided a more effective deterrent than other possible ratios. Thus by combining the solvents in certain ratios, the capability of cuticular penetration and therefore the effectiveness of the defensive secretions are adapted to their natural targets.  相似文献   

15.
The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest.  相似文献   

16.
An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.  相似文献   

17.
As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.  相似文献   

18.
Abstract: In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies—recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)—differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in‐migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.  相似文献   

19.
How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.  相似文献   

20.
Summary Acanthoscelides obtectus (Say) is one of the most damaging pests of kidney beans,Phaseolus vulgaris L. worldwide. However, aromatic plants from the families Lamiaceae, Lauraceae, Myrtaceae and Poaceae can protect kidney beans by direct or delayed insecticidal effect, through increased adult mortality and inhibition of beetle reproduction (both oviposition and adult emergence). The efficiency of hydrodistillated and intact plants fromThymus vulgaris andT. serpyllum, Mentha piperata, Rosmarinus officinalis, Satureia hortensis, Eucalyptus globulus, Laurus nobilis, Origanum vulgare, andCymbopogon nardus was compared. For both extracts,Origanum vulgare had the best effect. The insecticidal effect was induced by more than the essential oils because no significant difference was noticed between distilled and intact plants extract. Inhibition of reproduction was particularly important. These results suggest that lipidic as well as non lipidic, allelochemicals, such as phenolics, or non-protein amino-acids, or flavonoids may be involved in the toxicity of aromatic plants to this beetle.  相似文献   

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