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1.
各种霉菌污染着墙面、物品及食品,尘螨则以其排泄物、蜕皮及螨尸微粒折磨着90%的儿童及青年哮喘病患者,传染性疾病的患者散发的细菌、病毒则在通风不良的室内为患众人.因此,冬季室内的生物性传染,关系到千家万户的生活及健康水平,已经引起人们日益广泛的关注.本文通过对生物性污染的分析,提出了预防及治理冬季室内环境污染的必要性及可行的预防措施.仅供环境保护及建筑设计工作者参考.  相似文献   

2.
叙述环境教育的产生及发展,介绍目前环境保护及环境教育还存在的问题,讨论了开展环境教育的必要性及有利条件,及在县级开展环境教育的基本作法。  相似文献   

3.
文中主要论述了我国标准体系框架和分类及军用标准体系,研究了航天器环境工程标准体系及航天器动力学环境标准的发展及其与国外标准体系的关系,探讨了航天器动力学环境试验验证系统及验证标准的发展及作用,阐述了航天器力学环境试验标准与国外同行业的差距及发展方向。  相似文献   

4.
《环境保护》2017,45(6)
正面对机遇及瞬息万变的市场环境,不同城市及地区皆致力寻求可持续发展及绿色经济的增长,传统及新派的建筑模式在环境保护及减排上皆存在不少挑战。踏入十周年的2017澳门国际环保合作发展论坛及展览(2017 MIECF)特别举办绿色建筑行业交流会。绿色展览—绿色建筑展区与会者可掌握不少有关的资讯,包括有效减少能耗的建筑方法、适合都市  相似文献   

5.
云南高原湖泊污染底泥环境疏浚工程设计要点问题探析   总被引:1,自引:0,他引:1  
主要阐述了云南5个湖泊底泥环境疏浚与其它疏浚方式的区别以及与环境疏浚相关的技术参数,并指出在湖泊底泥环境疏浚工程设计及施工过程中应着重考虑的技术要点及措施,包括疏挖及输送方式的选择、疏浚设备类型的选择、疏浚区域的确定、挖泥厚度确定及精度要求、底泥处置及防渗处理、余水处理及排放等方面.  相似文献   

6.
电磁辐射污染危害浅析   总被引:2,自引:0,他引:2  
本文从电磁学及电动力学的角度,分析了电磁辐射对人体及金属仪器设备可能产生的危害及干扰,研究产生危害及干扰的机理,且简要提出对电磁辐射的防护方法.  相似文献   

7.
此文介绍了快辗技术的基本概念及特点,所用的实验设备的参数及实验结果。以及对实验结果的分析。最后就该技术的应用前景及所用设备的较佳参数做了简要的子测及设想。  相似文献   

8.
规划管制下农田生态补偿的研究进展分析   总被引:7,自引:0,他引:7  
基于特殊的土地基本国情,我国实施严厉的管制制度及措施强化对优质农田的保护及管理。然而,采取禁止性或限制性强的规划管制制度,严格限制或剥夺管制区域内相关群体使用资源和空间的权利,如未提供相应的补偿或经济援助,将侵害建设区和保护区内群体的发展机会及利益,导致不同分区利益群体福利非均衡,违背环境公平。论文从农田保护的政策绩效评价、发展受限制地区实施农田生态补偿制度的机理、农田外部效益及补偿标准的测度、农田管制损失补偿及外部效益产权界定、农田生态补偿制度实施绩效及福利效应研究等方面梳理总结了国内外关于规划管制下农田生态补偿的相关研究进展及发展动态,并提出在国家实施生态补偿机制及推进主体功能区划形成与落实等政策契机下,制定基于主体功能区划框架下的农田生态补偿机制及政策,有重要的理论及实践意义。  相似文献   

9.
介绍密闭电石炉炉气的利用及治理装置及技术。论述了直接燃烧法的电石炉气利用技术的工艺流程及设计炉气除尘系统过程。并讨论评估了直接燃烧法技术的优势及环境、经济和社会效果。  相似文献   

10.
浅析低气压对装备及元器件的影响   总被引:1,自引:1,他引:0  
总结了低气压对装备及元器件的影响研究情况,低气压对装备及元器件的影响主要分为五个方面,低气压对装备及元器件密封性能、散热性能、电性能、力学性能的影响,进而使得装备及元器件的整体使用效果受到影响,以及与其他环境因素综合作用对装备及元器件的影响。低气压环境因素降低了装备及元器件的使用效能,无法发挥应有的效能。研究分析结果将为相关论证、研制、生产、使用部门提供借鉴。  相似文献   

11.
Taihu Lake is one of the five biggest lakes in China. Surface water samples from 26 sampling sites of Taihu Lake were collected. Furthermore wet chemical analysis (CODCr and BOD5) and measurement of three dimensional excitation-emission matrix (3DEEM) spectra in the laboratory have been conducted. Using parallel factor analysis (PARAFAC) model, three components of colored dissolved organic matter (CDOM) have been identified successfully, based on the analysis of 3DEEM data. The characteristics of the three components also have been described by comparing them to some components of CDOM, identified in earlier researches. Meanwhile, spatial variations of concentration for the three components in Taihu Lake have been analyzed, and the result indicates that the concentration of component 1 depends more on the situation of wastewater pollution and can be used as the indicator of wastewater pollution. The relationship between the concentrations of the three components and results of the wet chemical analysis show that none of the three components can be used as indicators of gross organic matter in water. However, the concentrations of all the three components have obvious linear relationships with the BOD5 value, especially for component 1 (r = 0.72878). Finally, the potential applications of the composition analysis based on 3DEEM and PARAFAC model in water quality monitoring have been illuminated.  相似文献   

12.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

13.
The mechanism of flow turbulence, sediment supply conditions, and sediment transport patterns that affect the adsorption of cadmium ions onto sediment particles in natural waters are experimentally simulated and studied in this study both in batch reactors and in a turbulence simulation tank. By changing the agitation conditions, the sediment transport in batch reactors can be categorized into bottom sediment-dominated sediment and suspended sediment-dominated sediment. It is found that the adsorption rate of bottom sediment is much less than that of suspended sediment, but the sediment transport pattern does not affect the final (equilibrium) concentration of dissolved cadmium. This result indicates that the parameters of an adsorption isotherm are the same regardless of the sediment transport pattern. In the turbulence simulation tank, the turbulence is generated by harmonic grid-stirred motions, and the turbulence intensity is quantified in terms of eddy diffusivity, which is equal to 9.84F(F is the harmonic vibration frequency) and is comparable to natural surface water conditions.When the turbulence intensity of flow is low and sediment particles stay as bottom sediment, the adsorption rate is significantly low, and the adsorption quantity compared with that of suspended sediment is negligible in the 6 h duration of the experiment. This result greatly favors the simplification of the numerical modeling of heavy metal pollutant transformation in natural rivers. When the turbulence intensity is high but bottom sediment persists, the rate and extent of descent of the dissolved cadmium concentration in the tank noticeably increase, and the time that is required to reach adsorption equilibrium also increases considerably due to the continuous exchange that occurs between the suspended sediment and the bottom sediment.A comparison of the results of the experiments in the batch reactor and those in the turbulence simulation tank reveals that the adsorption ability of the sediment, and in particular the adsorption rate, is greatly over-estimated in the batch reactor.  相似文献   

14.
With 110-d incubation experiment in laboratory,the responses of microbial quantity,soil enzymatic activity,and bacterial community structure to different amounts of diesel fuel amendments were studied to reveal whether certain biological and biochemical characteristics could serve as reliable indicators of petroleum hydrocarbon contamination in meadow-brown soil,and use these indicators to evaluate the actual ecological impacts of 50-year petroleum-refining wastewater irrigation on soil function in Sbenfu irrigation area.Results showed that amendments of≤1000 mg/kg diesel fuel stimulated the growth of aerobic beterotrophic bacteria,and increased the activity of soil dehydrogenase,hydrogenperoxidase,polypbenol oxidase and substrate-induced respiration.Soil bacterial diversity decreased slightly during the first 15 d of incubation and recovered to the control level on day 30.The significant decrease of the colony forming units of soil actinomyces and filamentous fungi can be taken as the sensitive biological indicators of petroleum contamination when soil was amended with≥5000 mg/kg diesel fuel.The sharp decrease in urease activity was recommended as the most sensitive biochemical indicator of heavy diesel fuel contamination.The shifts in community structure to a community documented by Sphingomonadaceae withinα-subgroup of Proteobacteria could be served as a sensitive and precise indicator of diesel fuel contamination.Based on the results described in this paper,the soil function in Shenfu irrigation area was disturbed to some extent.  相似文献   

15.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

16.
Predicting long-term potential human health risks from contaminants in the multimedia environment requires the use of models. However,there is uncertainty associated with these predictions of many parameters which can be represented by ranges or probability distributions rather than single value.Based on a case study with information from an actual site contaminated with benzene,this study describes the application of MMSOILS model to predict health risk and distributions of those predictions generated using Monte Carlo techniques.A sensitivity analysis was performed to evaluate which of the random variables are most important in producing the predicted distributions of health risks.The sensitivity analysis shows that the predicted distributions can be accurately reproduced using a small subset of the random variables.The practical implication of this analysis is the ability to distinguish between important versus unimportant random variables in terms of their sensitivity to selected endpoints.This directly translates into a reduction in data collection and modeling effort.It was demonstrated that how correlation coefficient could be used to evaluate contributions to overall uncertainty from each parameter.The integrated uncertainty analysis shows that although drinking groundwater risk is similar with inhalation air risk,uncertainties of total risk come dominantly from drinking groundwater route.Most percent of the variance of total risk comes from four random variables.  相似文献   

17.
The contribution of aliphatic-rich plant biopolymer to sorption of hydrophobic organic compounds is significantly important because of their preservation and accumulation in the soil environment,but sorption mechanism is still not fully understood.In this study, sorption of 1-naphthol by plant cuticular fractions was examined to better understand the contributions of respective fraction.Toward this end,cuticular materials were isolated from the fruits of tomato by chemical method.The tomato cuticle sheet consisted of waxes (6.5 wt%),cuticular monomer (69.5 wt%),and polysaccharide (24.0 wt%).Isotherms of l-naphthol to the cuticular fractions were nonlinear (N value (0.82-0.90)) at the whole tested concentration ranges.The KodKow ratios for bulk cuticle (TC1),dewaxed cuticle (TC2),cutin (TC4),and desugared cuticle (TC5) were larger than unity,suggested that tomato bulk cuticle and cutin are much powerful solption medium.Sorption capability of cutin (TC4) was 2.4 times higher than the nonsaponifiable fraction (TC3).The 1-naphthol interactions with tomato cuticular materials were governed by both hydrophobic-type interactions and polar (H-bonding) interactions. Removal of the wax and polysaccharide materials from the bulk tomato cuticle caused a significant increase in the sorption ability of the cuticular material.There was a linear negative trend between K_(oc) values and the amount of polysaccharides or fraction's polarities ((N O)/C);while a linear positive relationship between K_(oc) values and the content of cutin monomer (linear R~2=0.993) was observed for present in the cuticular fractions.Predominant sorbent of the hydrophobic organic compounds (HOCs) in the plant cuticular fraction was the cutin monomer,contributing to 91.7% of the total sorption of tomato bulk cuticle.  相似文献   

18.
The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter (NOM). A relatively higher molecular weight (MW) of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.  相似文献   

19.
Two novel polymers (NJ-1 and N J-2) were synthesized by chemically modified a hypercrosslinked polymer NJ-0 with dimethylamine and trimethylamine, respectively. The comparison of the adsorption properties of the three polymers toward phenol, resorcin and phloroglucin was made. The study focused on the static equilibrium adsorption behaviors and the adsorption thermodynamics. Freundlich equation was found to fit the adsorption results well. The effect of amino groups introduced onto the surface of the resin and the structure of phenolic compounds on the adsorption were also studied. The hydrogen-bonding interaction and electrostatic interaction could happen between the amino groups and the adsorbates. The adsorption impetus increased as quantity of hydroxyl groups increased, but the adsorption capacity decreased due to the drop of the matching degree of the aperture of resins and the diameter of adsorbate molecules.  相似文献   

20.
Anatase TiO2 films were successfully prepared on foam nickel substrates by sol-gel technique using tetrabutyl titanate as precursor. The characteristics of the TiO2 films were investigated by XPS, XRD, FE-SEM, TEM and UV-Vis absorption spectra. The photocatalytic activities of TiO2 films were investigated by photocatalytic degradation reactions of gaseous acetaldehyde, an indoor pollutant, under ultraviolet light irradiation. It was found that Ni^2+ doping into TiO2 films due to the foam nickel substrates resulted in the extension of absorption edges of TiO2 films from UV region to visible light region. The pre-heating for foam nickel substrates resulted in the formation of NiO layer, which prevented effectively the injection of photogenerated electrons from TiO2 films to metal nickel. The TiO2 films displayed high photocatalytic activity for the degradation of acetaldehyde, and were enhanced by calcining the substrates and coating TiO2 films repeatedly. The high activity was mainly attributed to the improvement of the characteristics of substrate surface and the increase of active sites on photocatalyst.  相似文献   

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