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101.
利用高铝粉煤灰预脱硅液作为载体原料,通过使用胺基化合物对载体改性制备低温CO_2吸附剂.应用6 sigma中的工具,对制备工艺进行优化,得到理想的吸附剂,并对吸附剂样品进行表征.结果表明制备的CO_2吸附剂表现出良好的CO_2吸附性能.此类CO_2吸附剂具有吸附容量高(160 mg·g~(-1))、吸附速率快、对设备腐蚀低、成本低廉等特点,是一种极具工业应用潜力的CO_2吸附剂.  相似文献   
102.
通过研究高炉炉顶煤气中CO_2、H_2O和炉尘对低温钙基脱氯剂脱除HCl的影响发现:高炉炉顶煤气中,CO_2和H_2O含量增加,脱氯效果不同程度地变差;在不同位置的高炉炉顶煤气含炉尘范围内,重力灰含量增加,脱氯效果急剧变差;布袋灰含量低于10mg/m3时,布袋灰的含量增加脱氯剂的脱氯效果在一定程度上略有改善。  相似文献   
103.
分别以MDEA溶液和MDEA-TETA混合液为吸收剂对电厂烟气中的CO_2进行捕集.在相同的实验条件下,研究了吸收时间、吸收液浓度配比和反应温度对CO_2吸收率的影响,并对两种吸收剂的吸收效果进行对比分析.结果表明:吸收效率随着温度的升高而下降,温度低于45℃时,混胺吸收剂MDEA-TETA的吸收效率受温度的影响显著,温度高于45℃时,单一吸收剂MDEA的活化性能大幅度增强.MDEA-TETA混合液中两种胺的配比为6∶1,反应温度在25~65℃内,反应时间在5~20 min内时CO_2的吸收效果较佳,吸收率达90%以上,不同配比的混胺吸收剂的吸收效果均优于MDEA的吸收效果.  相似文献   
104.
二氧化碳捕集技术发展动态研究   总被引:3,自引:0,他引:3  
介绍了近年来新兴的二氧化碳捕集技术路线和国内外的有关研究项目。通过研究由清洁发展机制延伸出来的碳交易及其市场表明,在未来的几十年中,碳交易将成为最大的贸易商品,并且能够减少环境污染和产生较高的利益。  相似文献   
105.
在此对自制脱氯剂GH1与高温煤气中的氯化氢反应等温动力学与高温脱氯过程反应动力学进行了研究。等温动力学得出反应的反应级数为1,表观活化能为10.9kJmol。基于固定床反应器恒定模式行为,采用化学反应控制、产物层扩散控制及两种混合控制对脱氯过程的研究结果表明:自制脱氯剂GH1与高温煤气中的氯化氢气体的反应主要受化学反应控制,同时产物层的扩散控制是不容忽视的。  相似文献   
106.
Ecological distance-based spatial capture–recapture models (SCR) are a promising approach for simultaneously estimating animal density and connectivity, both of which affect spatial population processes and ultimately species persistence. We explored how SCR models can be integrated into reserve-design frameworks that explicitly acknowledge both the spatial distribution of individuals and their space use resulting from landscape structure. We formulated the design of wildlife reserves as a budget-constrained optimization problem and conducted a simulation to explore 3 different SCR-informed optimization objectives that prioritized different conservation goals by maximizing the number of protected individuals, reserve connectivity, and density-weighted connectivity. We also studied the effect on our 3 objectives of enforcing that the space-use requirements of individuals be met by the reserve for individuals to be considered conserved (referred to as home-range constraints). Maximizing local population density resulted in fragmented reserves that would likely not aid long-term population persistence, and maximizing the connectivity objective yielded reserves that protected the fewest individuals. However, maximizing density-weighted connectivity or preemptively imposing home-range constraints on reserve design yielded reserves of largely spatially compact sets of parcels covering high-density areas in the landscape with high functional connectivity between them. Our results quantify the extent to which reserve design is constrained by individual home-range requirements and highlight that accounting for individual space use in the objective and constraints can help in the design of reserves that balance abundance and connectivity in a biologically relevant manner.  相似文献   
107.
In the developing world, the exploitation of threatened species jeopardizes their permanence in the wild. Because not all captures are intentional, for instance when capture methods have low selectivity, pressure on these species may be lessened by releasing living incidentally caught animals. However, it is often unrealistic to expect people to voluntarily do so because it means foregoing the benefits of resource extraction. Financial incentives for such animal release may foster conservation objectives. Reducing human–animal conflicts, protecting natural habitat, and conserving nests of threatened species are examples of conservation benefits that can be built on financial reward systems. However, incentives aiming to protect unintentionally captured threatened species are scarce. We considered pay for release, a type of ecosystem-service payment designed to foster the release of incidentally captured threatened species. We aimed to determine the best conditions to implement this scheme, its potential benefits (e.g., incentivizing the release of threatened species), and pitfalls and priority research needs (e.g., required conditions for pay for release to work) to show that its global applicability is possible. Given that approaches solely based on education and law enforcement may be ineffective under some circumstances, we argue that pay for release can protect incidentally captured endangered species if used under conditions conducive for its success. When local participants’ intrinsic motivation for conservation is weak, but the release of incidentally live-caught animals into their habitats is readily achievable, pay-for-release schemes could jump start urgently needed conservation efforts against indiscriminate animal harvesting.  相似文献   
108.
As human history is changing on many fronts, it is appropriate for us to understand the different perspectives of major global challenges, of which, water is a major priority. The water resources in urban areas are either approaching or exceeding the limits of sustainable use at alarming rates. Groundwater table depletion and increasing flood events can be easily realized in rapidly developing urban areas. It is necessary to improve existing water management systems for high-quality water and reduced hydro-meteorological disasters, while preserving our natural/pristine environment in a sustainable manner. This can be achieved through optimal collection, infiltration and storage of stormwater. Stormwater runoff is rainfall that flows over the ground surface; large volumes of water are swiftly transported to local water bodies and can cause flooding, coastal erosion, and can carry many different pollutants that are found on paved surfaces. Sustainable stormwater management is desired, and the optimal capture measure is explored in the paper. This study provides commentary to assist policy makers and researchers in the field of stormwater management planning to understand the significance and role of remote sensing and GIS in designing optimal capture measures under the threat of future extreme events and climate change. Community attitudes, which are influenced by a range of factors, including knowledge of urban water problem, are also considered. In this paper, we present an assessment of stormwater runoff management practices to achieve urban water security. For this purpose, we explored different characteristics of stormwater runoff management policies and strategies adopted by Japan, Vietnam and Thailand. This study analyses the abilities of Japanese, Vietnamese and Thai stormwater runoff management policies and measures to manage water scarcity and achieve water resiliency. This paper presents an overview of stormwater runoff management to guide future optimal stormwater runoff measures and management policies within the governance structure. Additionally, the effects of different onsite facilities, including those for water harvesting, reuse, ponds and infiltration, are explored to establish adaptation strategies that restore water cycle and reduce climate change-induced flood and water scarcity on a catchment scale.  相似文献   
109.
The present study shows a new approach in modelling the hard coal fired Oxyfuel Cycle on the whole. The static process model comprises an Oxyfuel combustion principle applied to an existing state-of-the-art hard coal power plant located in Rostock, Germany. It includes the air separation unit and the flue gas liquefaction unit, which are modelled in detail. As one of the main advances to previous work, the closed simulation of all components in one model delivers a coherent solution with a significantly reduced number of assumptions. The model needs no interfaces between different stand alone simulation tools or manual iteration and transfer of internal variables. Results from a thermodynamic and economic feasibility study on this process are shown and areas relevant for future research are identified.

The present study shows the feasibility and prospective key figures of the technology under realistic, comparable and reproducible assumptions and boundary conditions. The basic engineering of the process with a detailed study of the necessary gas separation and flue gas handling technologies is undertaken in the effort to a first stage optimisation of the process.

The flowsheet tool Aspen Plus (TM) was used to simulate the overall process. This particular tool was chosen because it offers an advanced data library on chemical substances and allows the calculation of phase equilibria and real gas behaviour during air separation and flue gas liquefaction. Emissions, coal consumption and investment costs of the Oxyfuel power plant are compared to those of the original state-of-the-art hard coal power plant which is used as the reference case.  相似文献   
110.
为改善施工安全标识警示效果,减少盲视发生,探究不同位置特征下施工安全标识引发的自动化注意行为,采用改进的注意捕获试验范式,使用E-prime 2.0平台记录当事人的反应时长和判断正误,通过注意捕获量和判断正确率度量自动化注意效果,并进一步构建施工安全标识自动化注意加工模型,剖析自动化注意加工过程及机理。研究结果表明:初次视认发生时,安全标识引发的自动化注意受位置因素影响,具有正中最优、正方向加强、右侧抑制等特点;对标识的自动化注意由启动和加工2个环节构成,与共同作用于视觉通道的控制加工串行发生,在启动阶段受位置特征提供的有效刺激强度影响,在加工阶段消耗较少认知资源。  相似文献   
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