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51.
用氟离子电极测定土壤溶液中无机单核铝的实验验证   总被引:7,自引:0,他引:7  
本文在Al-F体系中、验证了氟离子电极直接电位法测定和区分溶液中无机单核铝结果的可靠性。研究结果表明,氟离子电极直接电位法测定结果的相对误差在±5%以内。在非25℃上,采用校正温度影响的平衡常数进行计算,结果与25℃条件下无明显差别。  相似文献   
52.
《Ambio》2022,51(9):1978
Blue Carbon Ecosystems (BCEs) help mitigate and adapt to climate change but their integration into policy, such as Nationally Determined Contributions (NDCs), remains underdeveloped. Most BCE conservation requires community engagement, hence community-scale projects must be nested within the implementation of NDCs without compromising livelihoods or social justice. Thirty-three experts, drawn from academia, project development and policy, each developed ten key questions for consideration on how to achieve this. These questions were distilled into ten themes, ranked in order of importance, giving three broad categories of people, policy & finance, and science & technology. Critical considerations for success include the need for genuine participation by communities, inclusive project governance, integration of local work into national policies and practices, sustaining livelihoods and income (for example through the voluntary carbon market and/or national Payment for Ecosystem Services and other types of financial compensation schemes) and simplification of carbon accounting and verification methodologies to lower barriers to entry.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01723-1.  相似文献   
53.
Permeation of Cu(II) from its aqueous solution through a supported liquid membrane (SLM) containing di(2-ethylhexyl)phosphoric acid (D2EHPA) carrier dissolved in coconut oil has been studied. The effects of Cu(II), pH (in feed), H2SO4 (stripping) and D2EHPA (in membrane) concentrations have been investigated. The stability of the D2EHPA-coconutoil has also been evaluated. High Cu(II) concentration in the feed leads to an increase in flux from 4.1 × 10-9 to 8.9 × 10-9 mol/(m2·s) within the Cu(II) concentration range 7.8×10-4-78.6×10-4 mol/L at pH of 4.0 in the feed and 12.4 × 10-4 mol/L D2EHPA in the membrane phase. Increase in H2SO4 concentration in strip solution leads to an increase in copper ions flux up to 0.25 mol/L H2SO4, providing a maximum flux of 7.4 × 10-9 mol/(m2·s). The optimum conditions for Cu(II) transport are, pH of feed 4.0, 0.25 mol/L H2SO4 in strip phase and 12.4 × 10-4 mol/L D2EHPA (membrane) in 0.5 (m pore size polytetrafluoroethylene (PTFE) membrane. It has been observed that Cu(II) flux across the membrane tends to increase with the concentration of copper ions. Application of the method developed to copper plating bath rinse solutions has been found to be successful in the recovery of Cu(II). rane. It  相似文献   
54.
干旱区的生态环境,特别是绿洲的开发,改变了地-气系统的能量交换。几年来对绿洲气候的研究、气候资料的分析和实地考察表明,新疆南部干旱区最近几年的戈壁绿洲开发已改变了整个地州的气候变化,使其变为有利于人类的生存和发展。在戈壁绿洲的开发利用与环境变化之间,存在着2种截然相反的反馈作用:环境变好→绿洲发展→环境更好→绿洲再发展;环境恶化→绿洲退化→环境更坏→绿洲再退化,甚至消失。决定这2种反馈作用的是大环境的变迁和绿洲开发利用中是否合理利用资源和按自然规律办事。本文针对此问题进行了论述。  相似文献   
55.
随着农村经济的快速发展,农村环境污染日益严重,生态环境日益恶化,严重制约了农村经济的可持续发展。本文就农村环境污染的现状、环境污染问题分析和解决对策方面进行了探讨。  相似文献   
56.
白洋淀湿地有"华北之肾"的称号,是京津冀地区的重要水源地之一.近年来白洋淀湿地显现出了生态退化的趋势,生态修复工作正在开展但成效不稳固.从生态系统整体性的角度全面评估白洋淀湿地的基本情况、生态修复工作开展情况,在此基础上提出生态修复过程中将会面临的问题,并提出解决路径.  相似文献   
57.
Territorial user rights for fisheries are being promoted to enhance the sustainability of small‐scale fisheries. Using Chile as a case study, we designed a market‐based program aimed at improving fishers’ livelihoods while incentivizing the establishment and enforcement of no‐take areas within areas managed with territorial user right regimes. Building on explicit enabling conditions (i.e., high levels of governance, participation, and empowerment), we used a place‐based, human‐centered approach to design a program that will have the necessary support and buy‐in from local fishers to result in landscape‐scale biodiversity benefits. Transactional infrastructure must be complex enough to capture the biodiversity benefits being created, but simple enough so that the program can be scaled up and is attractive to potential financiers. Biodiversity benefits created must be commoditized, and desired behavioral changes must be verified within a transactional context. Demand must be generated for fisher‐created biodiversity benefits in order to attract financing and to scale the market model. Important design decisions around these 3 components—supply, transactional infrastructure, and demand—must be made based on local social‐ecological conditions. Our market model, which is being piloted in Chile, is a flexible foundation on which to base scalable opportunities to operationalize a scheme that incentivizes local, verifiable biodiversity benefits via conservation behaviors by fishers that could likely result in significant marine conservation gains and novel cross‐sector alliances. Incentivar la Conservación de la Biodiversidad con Comunidades de Pesca Artesanal por medio de Derechos de Uso Territorial y la Innovación de Modelos de Negocio  相似文献   
58.
本文分析了21世纪城市环境发展所面临的各种挑战,并进一步指出了水资源短缺和水环境污染是21世纪城市环境的最大挑战者和威胁者。在此基础上,提出了解决的对策措施。  相似文献   
59.
A semiempirical mathematical model is proposed for estimating the dermal absorption of chemicals from dilute aqueous solutions, such as bath water. Absorption depends on the concentration of the chemical in water, the area of skin exposed, the time of exposure, and a permeation coefficient that depends importantly on the relative solubility of the material in lipids and water, among other factors not so easily modeled.  相似文献   
60.
通过对呼伦贝尔市自然条件、资源储备、生态环境的调查,分析该市在水环境、大气环境、固体废物排放以及生态环境等方面的污染现状,指出该市在环境保护方面所面临的问题,并选择适当的预测方案,预测在未来五年各类环境污染所带来的压力;探讨该市在水、大气、固废、生态环境等方面的优势及劣势,并在此基础上提出了解决对策。在环境规划中应该把握好经济发展与环境保护并重的方向,明确地方环境问题,有针对性地开展规划工作,重点地解决环境污染问题,因地制宜地开展环境保护与规划工作。  相似文献   
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