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61.
Previous comparative studies on environmental policies in the East and West mainly focused on relating differing features of environmental management to different political, social/economic, and ideological conditions in both systems. The present article attempts to identify common experiences. In this respect, an obvious similarity can be seen in the fact that environmental management in the East and West emerged as a regulatory “command and control” approach, which was supplemented later by economic incentives. The 1988 USSR Resolution “On the Radical Transformation of the System of Natural Conservation” introduces a set of economic instruments as one of its main elements. This is less a radical change of environmental policy than a determined acceleration of previous approaches. Existing and newly designed economic methodologies provoke a comparison with similar approaches in market economies. The economic methods designed in the 1988 resolution include charges for the use of natural resources and the emission of pollutants, which are notable for their firm commitment to reduce emissions even below set regulatory standards. While experiences with this approach may be of great interest for Western countries, liability regulations of the United States can be of great use for designing relevant provisions implementing the USSR resolution. A number of bilateral treaties have demonstrated already the political relevance of an East-West exchange of experience in environmental management.  相似文献   
62.
Increasing population and urbanization necessitate very large investments in municipal water supply. These investments could be more efficiently deployed if the impact of policy variables such as marginal pricing, metering, by-laws on lawn watering and plumbing fixtures, and higher summer charges were known. The paper in particular advocates the replacement of the present declining block rate by an increasing block rate. In order to know the impact of policy variables, a multiple regression model is built; the fitted model is tested against some data not included in calibrating the model. Next the impact of selected policy variables on the target variable (residential water demand during summer) is worked out for a new urban community of 200,000 people. The investment requirements may decrease appreciably as a result of a price increase when marginal (or commodity) charges are low but the impact of price changes when commodity charges are already high is less evident and non-price policy variables may be more effective in maintaining high quality water and also satisfying the constraint of limited budgets for municipal services.  相似文献   
63.
介绍了电除尘器在公路长隧道中的应用,对隧道电除尘器在隧道中的安装位置和台数进行了公式推导,并给出了应用实例。  相似文献   
64.
A novel polycyclodextrin-modified magnetic cationic hydrogel (PCD-MCH) was developed and its performance, kinetics and mechanism for the removal of reactive brilliant red X-3B (X-3B) were studied. The results showed that the zeta-potential of PCD-MCH was 32.8 to 16.7 mV at pH 3.0–10.5. The maximum X-3B adsorption capacity of PCD-MCH was 2792.3 mg/g. The adsorption kinetics could be well-described by the Weber–Morris model and the homogeneous surface diffusion model (HSDM). Diffusion stages corresponding to surface or film diffusion, intra-particle or wide mesopore diffusion, and narrow mesopore/micropore diffusion occurred at 0–120, 120–480 and 480–1200 min, respectively. The latter two diffusion stages were rate-controlling for X-3B adsorption kinetics. At the initial X-3B concentration of 600 mg/L, the diffusion coefficient (Ds) and external mass transfer coefficient in the liquid phase (kF) were 3 × 10?11 cm2/min and 4.68 × 10?6 cm/min, respectively. X-3B approaching the center of PCD-MCH particles could be observed at 360 min. At the end of the third diffusion stage, the Cp at q/qe = 0 was 45.20 mg/L, which was close to the homogeneous Cp value of 46 mg/L along the radius of PCD-MCH particles. At pH 3.0–10.0, PCD-MCH showed stable X-3B adsorption capacities. After five regeneration-reuse cycles, the residual adsorption capacity of regenerated PCD-MCH was higher than 892.7 mg/g. The corresponding adsorption mechanism was identified as involving electrostatic interactions, cyclodextrin cavities and hydrogen bonds, of which cyclodextrin cavities showed prominent capture performance towards dye molecules through the formation of inclusion complexes.  相似文献   
65.
普通电除尘器的控制采用固定的火花频率控制方式以及低压控制,不能随工况变化而改变,所以能耗大,效果差。新型电除尘器控制器采用火花电平跟踪、间隙供电、降功率振打等技术,有利于提高电除尘器收尘效率,降低粉尘排放,大幅度降低电能消耗。通过对某发电机组电除尘器40台高压控制柜进行控制技术及节能改造,证明新型电除尘器控制技术在保证效率的基础上可节电60﹪左右。  相似文献   
66.
试论环境保护投资与环保产业的发展   总被引:5,自引:0,他引:5  
本文针对国内学术界和政府部门在环境保护产业投资和环境保护投资方面的模糊认识,明确区分了环保投资与环保产业投资,阐释了狭义的环保投资概念和环保投资与环保产业市场化的关系,论述了环保投资对环保产业市场化的作用,并强调只有坚持以市场为导向,环保产业才能健康发展,本文还论述了在拓展市场业务的过程中,受需求牵引,环保产业必然会由以末端治理服务为主转向为企业生产全过程的服务为主,最终融于生产过程而转化为清洁生产行为或产品生命周期管理。  相似文献   
67.
提高电除尘器除尘效率措施的研究进展   总被引:1,自引:0,他引:1  
高军凯  黄超  田莉 《环境污染与防治》2007,29(10):763-766,780
电除尘器在粉尘治理领域发挥着极其重要的作用.简要介绍了影响电除尘器除尘效率的主要因素.综述了近年来提高电除尘器效率措施的研究进展.着重介绍了几种新型电除尘器的除尘机制及除尘试验结果,评论了其除尘性能和应用前景,并对进一步的研究方向提出了看法.  相似文献   
68.
燃煤电厂烟气降温过程中多环芳烃分布特征   总被引:1,自引:1,他引:0  
分别以燃用褐煤与烟煤无烟煤的2个电厂为例,研究2个电厂烟气降温过程中多环芳烃的分布及转化特征。研究表明,萘、菲、苯并[a]蒽和苯并[a]芘4种多环芳烃在烟气降温过程中呈过渡分子状态,在适当的条件下,存在相互转化的可能性;萘、菲、苯并[a]蒽和苯并[a]芘在不同的电厂随飞灰粒径变化所表现出来的吸附特性不同,颗粒的粒度影响多环芳烃的形成与吸附。在烟气降温过程中飞灰表面吸附的萘、菲、苯并[a]蒽和苯并[a]芘含量随着飞灰粒径的变小呈现出逐渐增加的趋势。  相似文献   
69.
Experiments have been conducted to gain insight into the credibility of sparging aqueous solutions as an electrostatic ignition hazard for sensitive hydrogen/air or fuel/oxygen mixtures (Minimum Ignition Energies of ∼0.017 mJ and ∼0.002 mJ, respectively, compared to ∼0.25 mJ for hydrocarbon/air mixtures). Tests performed in a 0.5 m3 ullage produced electric field strengths between 125 and 560 V m−1 for air flows of 5–60 l min−1, respectively, comprised of 2–4 mm diameter bubbles. Field strength can be related to the space charge and fitting to an exponential accumulation curve enabled the charge generation rate from the air flows to be estimated. This was observed to be directly proportional to the air flow and its magnitude was consistent with literature data for bubble bursts. The charge accumulation observed at laboratory scale would not be a cause for concern. On the basis of a simple model, the charge accumulation in a 27 m3 ullage was predicted for a range of air flows. It is apparent from such calculations that ignition of hydrocarbon/air mixtures would not be expected. However, it would seem possible that field strengths might be sufficient to cause a risk of incendive spark or corona discharges in moderately sized vessels with sensitive flammable mixtures.  相似文献   
70.
介绍了球团竖炉的烟尘排放特性,分析研究了影响静电除尘器工作性能的主要因素,总结了静电除尘改造工程中技术改进经验和运行管理所取得的经验。  相似文献   
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