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离子色谱法测定植物中的氯离子的方法初探 总被引:1,自引:0,他引:1
本文对离子色谱法测定植物中氯离子的可行性以及前处理方法进行了介绍,通过一定的前处理方法,减少了植物体系组份复杂对测定的干扰和对色谱柱的污染,并对氯离子进行了测定. 相似文献
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植物叶片中氟的测定一般采用离子选择电极法,离子色谱法对其测定还鲜见报道,本文对用离子色谱方法测定植物叶片中的氟进行了探讨。 相似文献
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采用微波消解法和国标回流法对同一标准样品和污水样品进行COD的测定,结果表明,微波消解法可大大缩短COD的测定时间,且操作简便,对标准样品的测定值与回流法基本一致,均在样品误差的正常范围内,适合批量样品监测.水样中的悬浮物会影响COD的测定准确度. 相似文献
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资源型城市的高质量发展具有重大的战略意义。为清晰认识中国资源型城市转型存在的问题以及高质量发展的路径,邀请来自不同领域的十位专家就当前资源型城市高质量发展的主要困境与突破路径等研究前沿进行访谈,访谈结果表明:中国资源型城市转型取得了巨大成绩,但距离高质量发展的要求仍有较大距离,突出表现在经济发展仍未能摆脱资源依赖的发展路径、推动高质量发展的新要素集聚偏弱和碳减排目标下资源型城市的内、外部均面临着巨大的压力;新时期需要重新认识资源型城市的作用和地位,提升资源型城市保障国家资源能源安全的能力;在深刻把握传统资源禀赋概念内涵基础上实现对新资源体系的再认知,注意挖掘新资源,充实资源型城市研究的新知识体系;要针对不同类型的资源型城市的发展条件,分类施策,因地制宜推动资源型城市的创新发展;要继续提高经济增长的就业弹性,增强经济发展拉动就业的能力,并充分重视就业机会的创造和培育;要加快探索绿色、高效的转型发展道路,同步实现“存量”的绿色化和“增量”的绿色性;要综合考虑资源型城市开发基础和要素资源条件,从传统的“增长和扩张型”转变为“高效增长与精明收缩结合型”发展模式;要整合新数据与新技术方法科学/智... 相似文献
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There have been many calls in policy and academia for more inclusiveness in science-policy interfaces, but there is as yet insufficient clarity as to what such inclusiveness means and how to achieve it in the context of international organisations. This paper analyses how inclusive the IPCC is across geographies and stakeholders. Building on the distinction between access and active participation, it examines the involvement of developing countries and NGOs in the Panel’s assessment process.The analysis shows that more inclusive institutional set-ups in international science-policy organisations do not automatically lead to greater credibility, salience and legitimacy of knowledge production processes (Mitchell et al., 2006). For instance, inclusive access does not per se guarantee active participation as the latter depends on a variety of factors including resources and the capacity of actors to engage. Furthermore, in institutional contexts the idea of inclusiveness is necessarily subject to operational interpretations. How these interpretations relate to the representativeness of those who participate in the process affects the relevance of knowledge to its users’ needs. Finally, there are political elements to inclusiveness as more powerful actors may be unwilling to renegotiate the balance of power to expand access to stakeholders.The paper concludes that these nuances should be taken into account in the IPCC and other international science-policy institutions. It also urges the Panel to address the developing country participation gap and explore institutional avenues for expanding access to non-state stakeholders in order to increase the credibility, salience and legitimacy of its processes and shift to solutions-oriented assessments. 相似文献
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The rains are disappointing us: dynamic vulnerability and adaptation to multiple stressors in the Afram Plains, Ghana 总被引:3,自引:0,他引:3
Lisa Westerhoff Barry Smit 《Mitigation and Adaptation Strategies for Global Change》2009,14(4):317-337
This paper builds on work on the dynamics of vulnerability and multiple stressors through a case study in the Afram Plains
of the Eastern region in Ghana. A vulnerability framework is applied in the community of Mimkyemfre to identify and explain
the multiple underlying political, socioeconomic and environmental forces that influence the ways in which people are exposed
and sensitive to climate, and their capacities to adapt to changing conditions. The results of the study indicate that the
community experiences a range of biophysical and socioeconomic conditions that contribute to its vulnerability. Vulnerability
was found to change over time and in some cases was cyclical, in that certain actions taken for the purposes of adaptation
were found to exacerbate existing vulnerabilities. Processes of vulnerability were also found to occur at several scales and
were experienced unevenly at the community level. The findings of this assessment have important implications for the design
and implementation of successful adaptation initiatives, both in Africa and elsewhere. In particular, they demonstrate the
need to understand the social, economic and institutional challenges to development as a basis for any contemplation of adaptation
to climate change. 相似文献
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为了探讨生物质燃烧过程中正构烷烃化学组成及其碳同位素的变化规律,对4种玉米秸秆进行了室内焚烧实验,用GC-MS和GC/C/IRMS方法对燃烧前后的样品进行测定.结果表明,秸秆中正构烷烃的碳数为C13~C35,分布形态为单峰型,主峰碳数为C31.正构烷烃的碳优势指数(CPI)值为1.1~5.3,平均碳链长度(ACL)为25.1~28.8.明火烟尘中正构烷烃的碳数为C14~C35,呈双峰型分布,2个主峰碳数分别是C18和C31.其CPI值为1.0~2.4,ACL值为23.0~26.8.正构烷烃单体碳同位素比值为-20.1‰~-33.5‰.闷烧烟尘中正构烷烃的碳数是C12~C35,CPI值为2.2~4.8,ACL值为26.6~28.9.其含量呈双峰式分布,2个主峰碳数分别是C22/C23、C31.正构烷烃单体碳同位素比值为-21.5‰~-32.5‰.在明火烟尘和闷烧烟尘中,正构烷烃的单体碳同位素组成与原秸秆中同碳数正构烷烃的差值分别为-13.8‰~5.4‰、-6.7‰~ -5.1‰.2种烟尘中正构烷烃的化学组成与碳同位素分布都与原玉米秸秆有着显著的差别. 相似文献
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为了改善ABR反应器的设计和运行,在实验室条件下,通过CFD(computational fluid dynamics,计算流体力学)技术和RTD(停留时间分布)曲线测试技术,分析不同结构参数下ABR反应器的流动和混合特性. 在此基础上,结合理论分析,确定ABR的最佳隔室数量. 结果表明:在反应器有效容积不变的情况下,随着ABR反应器内隔室数量由3个增至6个,ABR反应器内死区容积所占比例由15.51%降至1.87%,Pez(Peclet准数)由8.47升至16.67,N(串联数)由4.80升至8.88;隔室数量由3个增至4个、4个增至5个、5个增至6个时,死区容积所占比例的降幅分别为44.00%、74.50%、15.40%,Pez的增幅分别为36.88%、42.17%、32.57%,而N的增幅则分别为36.07%、1.95%、1.67%. 与5个隔室的ABR反应器相比,6个隔室的ABR反应器在死区容积所占比例、Pez和N等指标上尽管有所改善,但改善幅度已显著降低. 通过理论分析与混合参数模拟结果相结合,共同确定ABR反应器的最佳隔室数量为4个或5个. 相似文献
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The three basic principles of sustainable development, relating to ecology, economy and society, have long been embedded within national and international strategies. In recent years we have augmented these principles by a further seven considerations giving rise to the so-called 10-tenets of sustainable management. Whilst theoretically appealing, discussion of the tenets to date has been largely generic and qualitative and, until the present paper, there has been no formal and quantitative application of these tenets to an actual example. To promote the concept of successful and sustainable environmental management there is the need to develop a robust and practical framework to accommodate value judgements relating to each of the tenets. Although, as originally presented, the tenets relate specifically to management measures, they may also be applied directly to a specific development or activity. This paper examines the application of the tenets in both of these contexts, and considers their incorporation into an assessment tool to help visualise and quantify issues of sustainability. 相似文献
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结合鞍山市在创建国家环保模范城市工作过程中建设环境噪声达标区的工作实际,针对鞍山市区(建成区)的噪声达标区的划分、监测布点、监测方法和验收等创建过程中遇到的具体问题进行了分析,提出了相应的解决方法,并就创建过程中的不成功经验进行了总结.鞍山市的噪声达标区建设基本上符合国家和省关于环境噪声达标区的技术要求,虽然达标区的划分、现状调查、各种噪声数据监测和分析、噪声污染源的治理以及达标区的验收和噪声源的抽测等工作较为复杂,但仍可以为其他城市噪声达标区的创建提供借鉴. 相似文献
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人类为了满足生活和生产的需求,对森林资源的过度索取,已造成森林植被的毁坏及生态系统的自动调节能力的破坏,引起了生态失调甚至造成生态系统崩溃.森林植被破坏对人类社会发展造成了气候异常、温室效应等恶果.为此提倡中国的森林植被保护与可持续发展要从法制和管理方面入手,达到改善生态环境和森林资源持续发展及利用的目的. 相似文献
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中国人不会使世界挨饿 总被引:12,自引:0,他引:12
本文通过对中国国土资源食物生产潜力的比较全面、系统的分析,认为中国只要举国上下支持、保护和发展农业,强化国家对农业的主导作用,建立食物安全保障体系,认真执行"米袋子"省长负责制,加大对农业特别是对科技的投入力度,面向国土,开发国土,充分、合理利用国土,并相应地建立起具有中国特色的包括耕地、草地、林地、海洋和野生生物资源的食物来源的五大生产体系、符合中国国情的、具有浓厚东方色彩的消费体系、节粮体系以及推行人口计划控制政策,虽农业发展具有艰巨性,但前景依然是光明的。跨越新世纪,中国人定能养活中国人,中国人不会使世界挨饿。 相似文献
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Dickens JC 《Die Naturwissenschaften》2007,94(10):847-852
Chemical signals emitted by insects and their hosts are important for sexual communication and host selection. Plant volatiles
facilitate the location of suitable hosts for feeding and oviposition, and may moderate responses to sex and aggregation pheromones.
While mating has been shown to moderate behavioral responses to pheromones in a number of insects, little is known about the
effects of mating on behavioral responses of insects to plant attractants, and even less is known about the mechanisms involved.
In this study, mating was shown to decrease behavioral responses of the Colorado potato beetle to a host kairomone within
24 h, and attraction to the kairomone recovers only after 72 h. This decrease in responsiveness also occurs when only contact
with the opposite sex is allowed; the effect is not observed with contact among individuals of the same sex. Peripheral olfactory
responses to a component of the kairomone correlate with the observed behavioral responses and suggest involvement of antennal
receptors in the behavioral change. 相似文献