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生物多样性保护法律的有效执行,应立足于具体规制工具的设计。生物多样性保护立法涉及三个主要法律领域——物种保育法、自然保护地法和生物安全法,从法律规范层面分析,这三个法律领域对规制工具的偏好与选择呈现出"硬者极硬,刑罚优先,软者无力"的整体格局。本文以生物多样性保护原理对现行规制工具进行检验,物种保育法和自然保护地法应以规制领域的去极端化为导向进行规制工具更新,一方面要软化甚至去除极硬规制,与此同时应建立完善行政合同、行政指导、行政奖励等柔性规制工具,赋予其可操作性,使之柔而有力。 相似文献
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目的基于压电陶瓷的逆压电效应,以试验和仿真分析的方法研究压电陶瓷对某柔性板试验件振动控制的时效性能,为压电陶瓷如何保持长时间有效参与振动控制提供参考。方法搭建振动主动控制系统,实现柔性板的振动控制,以压电陶瓷驱动电压的降低模拟时效损伤。建立该结构的动力学有限元模型,并进行响应分析,以压电陶瓷产生的驱动力变小来模拟时效损伤。通过测定不同损伤程度的压电陶瓷参与振动控制前后的动响应,得到多种条件下的振动控制效率。结果当所有压电陶瓷的时效损伤程度均达到80%时,对某柔性板试验件的振动控制率降低为初始振动控制率的60.4%。基于试验与分析结果,评估多种条件下的振动控制率,得到了压电陶瓷时效损伤对柔性板振动控制的影响规律。结论压电陶瓷时效损伤对柔性板振动控制的影响可以用有限元仿真来模拟,压电陶瓷的时效损伤程度可通过调节它的驱动电压来进行测试。 相似文献
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循环经济产业体系论纲 总被引:9,自引:0,他引:9
循环经济的核心是物质在产业间和产业与环境间的循环流动。发展循环经济要落实到具体的产业和企业上。需搞清具有物质循环利用关系的产业及其间的关系。为区别传统经济产业间的关系,避免走入用传统产业理论指导循环经济建设的误区,本文提出产业体系和循环经济产业体系的概念。并将若干与某种生产要素有关的产业相互联系、相互制约而构成的整体称为产业体系。以物质要素循环利用关系为纽带的产业体系称为循环经济产业体系。根据物质在环境社会系统中的流动模式。将循环经济产业体系中的产业分成物资产业、人的产业和环境产业三大类。要在传统(线性)经济的基础上发展循环经济。需理性地按生态学原理规范经济活动。重点强化废弃物再生和回用的环境产业。使之同物资产业和人的产业相协调。产业体系是对产业结构概念的发展。循环经济产业体系是循环经济理论和建设的重要内容。构建循环经济理论体系、出台有关法律法规和产业政策。是循环经济建设工作的重点。 相似文献
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Machine-tools have been identified as one of the main energy-using products to be analyzed in an Ecodesign perspective, targeting the reduction of their environmental impact. Following this, machine-tool manufacturers are committed to anticipate eminent regulations and are looking for guidelines to improve their products on an effective and low-cost manner. This paper describes part of the energy consumption study followed in the frame of the Ecodesign of a commercial press-brake. All-hydraulic and all-electric commercially available systems, of different capacities and working in real production scenarios, have been included. From this study, a preliminary version of an LCI dataset for the bending process is proposed, structured in technology, machine capacity and usage mode categories, and using the bending cycle as the reference unit. The energy consumption per category was estimated based on a specific process energy model built as a function of the referred parameters. The contribution of the respective machine-tool structure to the environmental impact of the machining process is to be included, targeting the completion of such machining unit process dataset. The full LCA of an all-hydraulic system revealed the significant contribution of the machine-tool structure to the global life-cycle environmental impact of the machine (about 40%), while electricity during use phase contributes with about 46% to the total impact. This contradicts the general results published for other metal and non-metal forming processes, and is understood to be related with the discrete loading character of such forming processes here discussed. 相似文献
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Ashutosh Bahugun Madhuri K. Lily Ashok Munjal Ravindra N. Singh Koushalya Dangwal 《环境科学学报(英文版)》2011,23(6):975-982
A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene (DBT) was isolated from diesel contaminated
soil. The DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7 (NCBI GenBank Accession No. GQ496620)
using 16S rDNA gene sequence analysis. The desulfurized product of DBT, 2-hydroxybiphenyl (2HBP), was identified and
confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis respectively.
The desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr, exponentially
increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the DBT. However, further growth
resulted into DBT degradation. The induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase
within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization
pathway of DMT-7. In addition, Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole
source of sulfur such as benzothiophene, 3,4-benzo DBT, 4,6-dimethyl DBT, and 4,6-dibutyl DBT. Therefore, Lysinibacillus sphaericus
DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol. 相似文献
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