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181.
我国再生资源产业发展初具规模,回收体系发生很大变化,形成一些区域性集散地和交易市场,技术水平有所提高。再生资源产业发展成为资源供应的重要补充,有助于实现“十一五”节能降耗减排目标,提供大量就业机会,带动地方经济发展。但也存在监管不到位,市场秩序混乱,回收环节多,企业规模小,技术水平低,一次污染问题突出,废物进口配额管理不完善,法规不健全,认识不到位等问题。 相似文献
182.
183.
本文分析了我国环保产业的现状及存在的问题 ,从环保产业市场的培育、实现环保产业的升级和跨越式发展提出了发展对策的建议 相似文献
184.
Axel Hochkirch Michael J. Samways Justin Gerlach Monika Böhm Paul Williams Pedro Cardoso Neil Cumberlidge P. J. Stephenson Mary B. Seddon Viola Clausnitzer Paulo A. V. Borges Gregory M. Mueller Paul Pearce-Kelly Domitilla C. Raimondo Anja Danielczak Klaas-Douwe B. Dijkstra 《Conservation biology》2021,35(2):502-509
Measuring progress toward international biodiversity targets requires robust information on the conservation status of species, which the International Union for Conservation of Nature (IUCN) Red List of Threatened Species provides. However, data and capacity are lacking for most hyperdiverse groups, such as invertebrates, plants, and fungi, particularly in megadiverse or high-endemism regions. Conservation policies and biodiversity strategies aimed at halting biodiversity loss by 2020 need to be adapted to tackle these information shortfalls after 2020. We devised an 8-point strategy to close existing data gaps by reviving explorative field research on the distribution, abundance, and ecology of species; linking taxonomic research more closely with conservation; improving global biodiversity databases by making the submission of spatially explicit data mandatory for scientific publications; developing a global spatial database on threats to biodiversity to facilitate IUCN Red List assessments; automating preassessments by integrating distribution data and spatial threat data; building capacity in taxonomy, ecology, and biodiversity monitoring in countries with high species richness or endemism; creating species monitoring programs for lesser-known taxa; and developing sufficient funding mechanisms to reduce reliance on voluntary efforts. Implementing these strategies in the post-2020 biodiversity framework will help to overcome the lack of capacity and data regarding the conservation status of biodiversity. This will require a collaborative effort among scientists, policy makers, and conservation practitioners. 相似文献
185.
深水水下分离器服役过程中由于腐蚀、地质灾害和环境高压作用,存在失效泄漏风险。针对2 000 m超深水水下分离器可能存在的失效泄漏问题,基于计算流体动力学CFD方法,建立分离器失效泄漏后果数值仿真分析模型,对分离器泄漏场景进行模拟与分析,研究2 000 m水深条件下分离器泄漏油气扩散规律,并考虑不同泄漏位置对油气扩散行为的影响。结果表明:水下分离器泄漏包括压力扩散和自由扩散两个阶段,压力扩散阶段历时极短,自由扩散阶段耗时较长;泄漏口位置对泄漏结果有较为明显的影响,分离器上部泄漏,油气全部溢出,分离器中下部泄漏,大部分油气保留于分离器内部,最终形成分明的油气水界面;分离器内部压力随时间迅速上升,t=0.25 s左右接近于20 MPa,后期在20 MPa左右呈极微小波动,泄漏速率随分离器内部压力增大迅速减小,达到最低点之后,呈微小波动状变化。 相似文献
186.
Ram B. Jain 《毒物与环境化学》2016,98(1):137-148
National Health and Nutrition Examination Survey (NHANES) uses two tobacco use surveillance questionnaires. One is administered during an at-home interview (HI) and the other, during an examination session at a mobile examination center (MEC). NHANES data for the years 1999–2012 were used to evaluate the consistency of responses to tobacco surveillance questions in HI and MEC interview. In addition, accuracy of self-reported smoking status was evaluated. Of those who reported to be daily cigarette smokers during HI, 18.7% reported to be either some-day smokers or nonsmokers during MEC interview. Of those who reported to be some-day cigarette smokers during HI, 22.1% reported to be daily smokers and 17.5% reported to be nonsmokers. Also, 4.1% of those who reported to be nonsmokers during HI reported to be either daily or some-day smokers during MEC interview. Using serum cotinine measurements taken during MEC interview, 27.1% were found to be smokers and 72.9% were found to be nonsmokers. In general, a moderate to high agreement, as measured by the κ statistic, was found between the self-reported responses to tobacco use questions during the home and MEC interviews as well as between smoking statuses based on self-reported and serum cotinine measurements. 相似文献
187.
为研究蒲河中致嗅类VOSCs(挥发性有机硫化物)的污染水平、空间分布及其影响因素,采用吹扫捕集(P&T)与气相色谱(GC)/火焰光度检测器(FPD)联用方法,测定水样中14种致嗅类VOSCs的质量浓度,采用相关性分析确定水质因子〔ρ(DO)、ρ(NH3-N)、ρ(CODCr)、ρ(BOD5)〕对ρ(∑VOSCs)空间分布的影响. 结果表明:所调查的27个采样点中各目标化合物均有检出,ρ(∑VOSCs)的范围为85.82~1 766.04 ng/L;DMS(甲硫醚)为最主要的污染物,ρ(DMS)平均值为114.29 ng/L,检出率为96.30%,变异系数为0.42. ρ(DO)与ρ(∑VOSCs)显著相关,Pearson相关系数为-0.751,对ρ(∑VOSCs)的空间分布影响最大;其次是ρ(NH3-N),Pearson相关系数为0.441;ρ(CODCr)和ρ(BOD5)与ρ(∑VOSCs)不相关. 相似文献
188.
Cristina Munari 《Chemistry and Ecology》2014,30(7):653-665
We gathered water and macrobenthic data over a 5-year period in the Valli di Comacchio, the largest lagoons in the Po River Delta (northern Adriatic), to evaluate the response of ecological indices and to test their sensitivity against environmental variables. Of 84 sampling points, only 12 exhibited a good/high ecological quality status according to the BITS and 28 according to the M-AMBI. Environmental variables representative of eutrophication did not correlate with the indices. The impacts experienced by the Valli during the last 30 years seem to have led to disruption of the pelagic–benthic food web. Eel fisheries, whose management is traditionally characterised by long water residence time, thus seem inconsistent with restoration purposes. 相似文献
189.
The consequence modelling package Phast examines the progress of a potential incident from the initial release to the far-field dispersion including the modelling of rainout and subsequent vaporisation. The original Phast discharge and dispersion models allow the released substance to occur only in the vapour and liquid phases. The latest versions of Phast include extended models which also allow for the occurrence of fluid to solid transition for carbon dioxide (CO2) releases.As part of two projects funded by BP and Shell (made publicly available via CO2PIPETRANS JIP), experimental work on CO2 releases was carried out at the Spadeadam site (UK) by GL Noble Denton. These experiments included both high-pressure steady-state and time-varying cold releases (liquid storage) and high-pressure time-varying supercritical hot releases (vapour storage). The CO2 was stored in a vessel with attached pipework. At the end of the pipework a nozzle was attached, where the nozzle diameter was varied.This paper discusses the validation of Phast against the above experiments. The flow rate was predicted accurately by the Phast discharge models (within 10%; considered within the accuracy at which the BP experimental data were measured), and the concentrations were found to be predicted accurately (well within a factor of two) by the Phast dispersion model (UDM). This validation was carried out with no fitting whatsoever of the Phast extended discharge and dispersion models. 相似文献
190.
《Process Safety and Environmental Protection》2014,92(1):3-16
This paper discusses the validation of discharge and subsequent atmospheric dispersion for both unpressurised and pressurised carbon dioxide releases using the consequence modelling package Phast.The paper first summarises the validation of the Phast dispersion model (UDM) for unpressurised releases. This includes heavy gas dispersion from either a ground-level line source (McQuaid wind-tunnel experiments) or an area source (Kit-Fox field experiments). For the McQuaid experiments minor modifications of the UDM were made to support line sources. For the Kit Fox experiments steady-state and 20-s finite-duration releases were simulated for both neutral and stable conditions. Most accurate predictions of the concentrations for finite duration releases were obtained using the UDM Finite Duration Correction method.Using experiments funded by BP and Shell and made available via DNV's CO2PIPETRANS JIP, the paper secondly summarises the validation of the Phast discharge and dispersion models for pressurised CO2 releases. This modelling accounted for the possible presence of the solid CO2 phase following expansion to atmospheric pressure. These experiments included both high-pressure steady-state and time-varying cold releases (liquid storage) and high-pressure time-varying supercritical hot releases. Both the flow rate and the concentrations were found to be predicted accurately.The above validation was carried out with no fitting whatsoever of the Phast extended discharge and dispersion models. 相似文献