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1.
《环境工作通讯》2010,(4):I0007-I0013,I0006
全国农村环境保护暨生态建设示范工作现场会就要结束了。两天半会议期间,大家听取了周生贤部长的重要讲话,对浙江省宁波市农村环境综合整治和生态示范建设情况进行了实地考察,交流了各自的经验和做法,提出了建设性的意见和建议。大家认为,这次会议学习了经验,领会了精神,受到了鼓舞,增强了信心,明确了方向,强化了责任。在大家的共同努力下,会议达到预期目的,取得圆满成功。  相似文献   

2.
为了进一步提高HSE管理水平,切实加强采油队在施工中的风险管理,我们在采油队推行了HSE作业指导书,实施以来,增强了职工的HSE意识,规范了HSE管理,有效地防范了作业风险,取得了良好效果.  相似文献   

3.
介绍了饮料制造业实施清洁生产的途径和措施,提出了清洁生产的实施要体现"开源节流"的战略思想;以清洁生产理论为依据,制定和实施了36条清洁生产方案,最大限度地提高原物料的利用率,降低了能耗,提高了产品质量,减少了污染;获取了额外的成本降低,增强了产品市场竞争力,实现了企业经济效益和环境效益的统一。  相似文献   

4.
多媒体技术的发展使小学数学教学模式发生了根本性变化。课堂体现了学生的主体性原则,多媒体的应用丰富了教学内容,灵活了教学方式,点燃了学生思维的火花,提高了学生听课效率,有效解决了数学教学中的重难点,多媒体是小学数学教学的得力助手。  相似文献   

5.
随着我国经济的高速发展,带来了一系列的环境问题,其中,农村水环境的污染矛盾日益突出,制约了新农村的建设.针对乡村污染现状,本文综述了当前我国农村水体污染现状,分析了其主要原因,提出了相应的对策,并对未来进行了展望.  相似文献   

6.
应用故障树分析法,对潜射武器通道可靠性进行了分析,建立了该系统的故障树,并在此基础上计算了武器通道的可靠性参数.讨论了部件的概率重要度和关键重要度,结合所建的故障树给出了相应的结果.通过重要度分析,找到了提高系统可靠性的途径.  相似文献   

7.
2006年起,广西壮族自治区地震局把做好政务信息工作摆上了重要议事日程,安排了专人负责,落实了措施,落实了专项经费,政务信息工作发生了质的飞跃.特别是信息管理员制度和激励机制从根本上改观了政务信息往日的面貌.本文介绍了广西壮族自治区地震局电子政务信息工作在事业发展中的定位、主要做法、成效和经验,意在抛砖引玉,加强学习和交流.  相似文献   

8.
沸石的投加,降低了污泥的比阻,提高了污泥的水通量,改善了污泥膜分离效果,钝化了污水中的重金属,吸附了污水中的难降解有机物,但同时降低了污泥的体积压缩性能,改变了污泥的成分,显著增加了Si、Al、K、Na等无机组分,并对污泥的资源化途径带来了影响。  相似文献   

9.
基于粗糙集的有机涂层腐蚀损伤综合评定模型   总被引:1,自引:0,他引:1  
运用粗糙集理论对评定涂层腐蚀损伤的9个单项指标进行了约简,消除了冗余信息,提高了评定效率,并依据粗糙集的属性重要性确定了相应评定指标的权重,消除了传统方法计算权重的主观性,增强了综合评定结果的可靠性,最终建立了有机涂层腐蚀损伤综合评定模型。通过对不同防护涂层的飞机典型结构试验件加速腐蚀试验的结果分析,验证了模型的可行性,并定量得到了不同涂层腐蚀损伤的综合评定等级。  相似文献   

10.
介绍了近年来生物絮凝剂的研究和应用现状,详细总结了几种生物絮凝剂的絮凝机理,并对生物絮凝剂的分类进行了阐述,列举了生物絮凝剂的应用情况,文中还提到了近年来的研究新进展,特别是提到了复合型生物絮凝剂的研制情况,最后文章对未来生物絮凝剂的发展趋势进行了叙述.  相似文献   

11.
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   

12.
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   

13.
To evaluate the influence of lactic acid on the methanogenesis, anaerobic digestion of kitchen wastes was firstly conducted in a two-phase anaerobic digestion process, and performance of two digesters fed with lactic acid and glucose was subsequently compared. The results showed that the lactic acid was the main fermentation products of hydrolysis-acidification stage in the two-phase anaerobic digestion process for kitchen wastes. The lactic acid concentration constituted approximately 50% of the chemical oxygen demand (COD) concentration in the hydrolysis-acidification liquid. The maximum organic loading rate was lower in the digester fed with lactic acid than that fed with glucose. Volatile fatty acids (VFAs) and COD removal were deteriorated in the methanogenic reactor fed with lactic acid compared to that fed with glucose. The specific methanogenic activity (SMA) declined to 0.343 g COD/(gVSS-d) when the COD loading were designated as 18.8 g/(L-d) in the digester fed with lactic acid. The propionic acid accumulation occurred due to the high concentration of lactic acid fed. It could be concluded that avoiding the presence of the lactic acid is necessary in the hydrolysis-acidification process for the improvement of the two-phase anaerobic digestion process of kitchen wastes.  相似文献   

14.
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   

15.
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   

16.
Black carbon (BC) can strongly adsorb hydrophobic organic compounds (HOCs).The HOC sorption to coated BC could be attenuated in soil and sediment compared with that of the parent BC.To study the potential causes of the sorption attenuation,humic acid (HA) and BC were isolated.Phenanthrene (PHE) was selected as the representative of HOCs.BC was coated with the precipitated HA.The PHE sorption to the HA-coated BC was determined.The HA coatings on BC could result in the significant sorption attenuation of PHE to BC.The attenuation varied in different HA origin and was positively correlated to the aromaticity of HA.The attenuation could be explained by the direct competition between HA and PHE for the available sorption sites on BC and the reduction of the available sorption sites as a result of the pore blockage of BC caused by the HA coatings.Therefore,the HA coatings on BC was one potential cause of the attenuation of HOC sorption to BC in soil and sediment.  相似文献   

17.
Actual textile wastewater and synthesized wastewater containing various textile dyes were photocatalytic degraded by the UVH2O2Fs-TiO2 process in an aimular-flow photocatalytic reactor. In this process, a photon kinetic-measure was adopted to obtain constant rates of dyes decomposition. It was theorized that, by illumination at different UV frequencies, the electrons within the semiconductor were excited from the valence band to the conduction band, yielding the formation of electron-hole pairs which are the pre-requisites for photocatalysis. CPT (critical photonic time) exposure required to cause 90% of vibrations between the double and single bonds along the molecular chain of the dyes to be oxidized, was taken to measure the photocatalytic activities. The CPTs varied with the frequencies of the UV spectral areas. The derivatization of CPT from the first-order kinetic law was presented.  相似文献   

18.
This paper presents the experimental investigations of the emissions of SO2, NO and N2O in a bench scale circulating fluidized bed combustor for coal combustion and co-firing coal and biomass. The thermal capacity of the combustor is 30 kW. The setup is electrically heated during startup. The influence of the excess air, the degree of the air staging, the biomass share and the feeding position of the fuels on the emissions of SO2, NO and N2O were studied. The results showed that an increase in the biomass shares resulted in an increase of the CO concentration in the flue gas, probably due to the high volatile content of the biomass. In co-firing, the emission of SO2 increased with increasing biomass share slightly, however, non-linear increase relationship between SO2 emission and fuel sulfur content was observed. Air staging significantly decreased the NO emission without raising the SO2 level. Although the change of the fuel feeding position from riser to downer resulted in a decrease in the NO emission level, no obvious change was observed for the SO2 level. Taking the coal feeding position R as a reference, the relative NO emission could significantly decrease during co-firing coal and biomass when feeding fuel at position D and keeping the first stage stoichiometry greater than 0.95. The possible mechanisms of the sulfur and nitrogen chemistry at these conditions were discussed and the ways of simultaneous reduction of SO2, NO and N2O were proposed.  相似文献   

19.
中西部地区的改革发展与沿海要素西移   总被引:2,自引:0,他引:2  
邹蓝 《自然资源学报》1998,13(3):267-272
沿海企业因成本全面上升和资源分布格局的变化开始向西转移扩张。这对于缺乏投资而改革与发展滞后的内陆地区有促进发展和改革的双重意义。沿海由此为新产业发展让出空间,调整自己的产业结构;中西部则因要素注入而得以加速企业改革和发展,缩小中国区域发展差距。中央和地方政府政策和角色均应作调整,以方便和鼓励产业向西转移。  相似文献   

20.
The adsorption behavior of p-aminobenzoic acid and o-aminobenzoic acid onto the different polymeric adsorbents was systematically investigated as a function of the solution concentration and temperature.Experimental results indicated that the equilibrium adsorption data of the four polymeric adsorbents fitted well in the Freundlich isotherm.The adsorption capacity of multi-functional polymeric adsorbent NJ-99 was the highest,which might be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of aminobenzoic acid.The adsorption capacity of o-aminobenzoic acid onto any adsorbent was higher than p-aminobenzoic acid.Thermodynamic studies suggested the exothermic,spontaneous physical adsorption process.Adsorption kinetics results showed that the adsorption followed the pseudo-second-order kinetics model and the intraparticle mass transfer process was the rate-controlling step.  相似文献   

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