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1.
研究用壳聚糖、聚铝和助剂A复合制备出一种成本低、絮凝效果好、出水Al3 含量少的新型自来水处理絮凝剂,并确定其最佳配比(体积比)为:0.1%壳聚糖:2%聚合氯化铝:0.1%助剂A=1:6:5.与传统聚铝类絮凝剂相比,其出水浊度和Al3 含量分别下降了2.97%和10.7%,并且药剂成本下降6.25%,有明显的经济和环境效益.  相似文献   

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介绍了水刺复合工艺的优点,分析了新型水刺复合滤料的三种先进形式—针刺与水刺、纺粘与水刺、机织与水刺的特点及其市场应用领域,为滤料研究提出了新的方向。  相似文献   

4.
通过实验室水培试验研究不同浓度处理水平下Cu、Cd、Hg单一及其复合污染对少根紫萍叶绿素及脯氨酸浓度的影响。经观察分析,培养4天后,各处理组均呈现出不同程度的受害症状。同一浓度处理水平下,单一重金属污染对少根紫萍叶绿素的生态毒性效应为Cd>Cu>Hg。复合污染中Cu+Cd和Hg+Cu+Cd对叶绿素的影响则表现为协同作用;Cd+Hg复合浓度≤6.0+4.0mg/L时表现为拮抗作用,复合浓度>6.0+4.0mg/L时表现为协同作用;Cu+Hg复合浓度≤0.4+4.0mg/L时表现为协同作用;复合浓度>0.4+4.0mg/L时表现为拮抗作用。随处理浓度的递增,脯氨酸含量均表现出一显著抗性峰,而后下降。  相似文献   

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清灰周期与阻力是除尘器的主要技术性能指标。本文研究了粉尘浓度及荷电粉尘对清灰周期与阻力的影响,总结了影响电袋复合除尘器性能的主要因素,介绍了电袋复合除尘器的应用实例,并分析了电袋复合除尘器的适用性。  相似文献   

6.
我国粉煤灰和铝、铁片固体废物产量日益增多,危害越来越严重。在高温加热、搅拌条件下,用强酸浸渍粉煤灰和易拉罐碎片,使粉煤灰和废旧铝、铁片资源化,制得废旧铝、铁片粉煤灰复合混凝剂,并用所制得的废旧铝、铁片粉煤灰复合混凝剂处理屠宰废水。在一定条件下,经混凝试验处理后的屠宰废水pH值在7左右,COD去除率为92.0%,SS去除率为98.7%,浊度去除率为98.4%,色度去除率为96.6%。结果表明,粉煤灰和废旧铝、铁片资源化和在废水处理中的应用具有可行性。  相似文献   

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在无机高分子絮凝剂聚合氯化铝(PAC)中引入有机高分子水解聚丙稀酰胺(PHP),制备出一种复合絮凝剂JX-3。PAC和PHP在其中可起到电性中和及絮凝桥架的的双重作用,使絮团紧密结合,提高絮凝效果,室内评价试验表明JX-3处理含轻油污水效果优于PAC和聚丙稀酰胺(PAM)。  相似文献   

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超积累植物在修复土壤重金属污染中起着重要的作用,但由于重金属复合污染的存在,许多植物并未能完全适用于实际修复中。本文通过阐述土壤重金属复合污染,参考近年来国际上对超积累植物富集机理的研究,从土壤重金属复合污染自身的交互作用,超积累植物根系活化机理,吸收和运输通道机制,金属配位体的运输与解毒作用,以及细胞分室化现象等各个阶段探讨与展望土壤重金属复合污染修复研究问题。  相似文献   

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主要利用珙桐叶的抗癌、防癌、抗氧化等特性,结合传统中医理论,将其与绿茶、余甘子、甜叶茶进行科学配伍,对珙桐叶的复方袋泡茶加工工艺进行研究,期望通过对珙桐资源的开发来促进珙桐由被动保护向主动保护转变,从而达到生态效益与经济效益双赢的目的。  相似文献   

10.
本文较系统地研究了提钛后的残渣、矿渣、熟料、激化剂等因素对复合水泥与少熟料水泥强度的影响;找出了利用提钛后的残渣生产复合水泥与少熟料水泥生产的最佳条件,并对复合水泥和少熟料水泥的性能进行了初步探索。试验数据表明,利用提钛后残渣可生产525^#复合水泥和425^#少熟料水泥,工业废渣利用率可达70%。  相似文献   

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通过对华东主要饮料市场的调研,结合国内外的相关报道,就饮料植物在人民生活中的地位、饮料植物种类、开发利用现状进行了综述,并提出利用前景.  相似文献   

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干旱胁迫下壳聚糖对花生幼苗生理特性的影响   总被引:1,自引:0,他引:1  
为了研究壳聚糖对花生幼苗抗旱言的影响,以花生品种“花育23号”为材料,在干旱胁迫下,用不同浓度的壳聚糖溶雍处理花生幼苗,连续处理5d后测定叶绿素、可溶性蛋白、MDA和脯氨酸的含量变化。结果表明,花生幼苗在干旱条件下喷施壳聚糖与蒸馏水相比,在干旱第10天叶绿素含量提高了42.2%,MDA含量降低了36.2%;在干旱第6天,可溶性蛋白含量提高了129.0%;在干旱第8天,脯氨酸含量提高了257.0%。喷施壳聚糖溶液的最适宜浓度为0.10g/L,喷施该浓度壳聚糖可促进植物生长,增强抗旱性。  相似文献   

13.
以高抗黄曲霉花生品种J11、中抗品种HY22和敏感性品种JH1012为材料进行黄曲霉侵染,在不同时间段取样测定各品种花生种皮和籽仁的毒素含量,并同时测定籽仁中脂肪酸和亚油酸、油酸含量。结果表明,各花生品种的种皮内毒素含量随侵染时间增加而升高,到最大值后保持稳定;而籽仁中的毒素含量较低,不同品种花生受侵染后毒素含量大小表现为高抗品种〈普通品种〈高感品种。亚油酸和脂肪含量与黄曲霉毒素含量呈显著正相关,而油酸呈显著负相关,说明高油酸含量和低脂肪、亚油酸含量的花生品种对黄曲霉毒素的侵染有一定抵抗作用。  相似文献   

14.
分析了我国餐饮产业的特点与面临的问题,提出了餐饮业集群发展的战略选择.以安徽省芜湖市凤凰美食街为例,从餐饮产业集群发展形成的背景、区位依托、构成要素以及竞争优势等方面对餐饮业的集群发展进行了实证分析.  相似文献   

15.
钛白废液直接排放会严重危害附近居民的生活及工农业的生产和发展,造成资源的严重浪费,应针对钛白废液的不同特性进行分类处理。总结了近年来国内外钛白液的各种治理、回收及综合利用等方法。  相似文献   

16.
流域复合系统可持续发展的评价研究   总被引:5,自引:0,他引:5  
本文以水文循环的基本单元“流域”为研究空间,以流域中人和自然构成的复合系统为研究对象,建立了流域复合系统可持续发展的评价指标体系及指标体系的基本结构,并对 江上中持续发展进行了定量评价 。  相似文献   

17.
兰州市生态环境与可持续发展初探   总被引:2,自引:0,他引:2  
虎陈霞 《青海环境》2001,11(1):27-29,32
文章在分析兰州市生态环境现状的基础上,探讨了导致兰州市生态环境恶化的原因与危害,提出了兰州市生态环境治理的思路与治理对策。  相似文献   

18.
Preliminary surveys are used to prioritize between contaminated sites to select those to be investigated more thoroughly. The data-gathering steps are almost identical between countries; however, the assessment procedures differ significantly. In this study, we have investigated 21 contaminated sites assessed as belonging to the high-risk or the very high-risk class using the Swedish Methods for Inventories of Contaminated Sites (MICS). We then applied the US Preliminary Assessment (PA) method to the same sites and compared the results and conclusions from the two screening procedures. In both cases, all sites were recommended for further investigation and the two approaches seem to corroborate one another; however, the PA assessment scores and the preliminary MICS classifications did not correlate. The results obtained with the PA method were easier to explain than the final MICS classification. The PA method also seems more transparent and easier to standardize, although objections could be made regarding the weighting scheme, because the outcome in this study was entirely dependent on the surface exposure pathway. However, to examine this in greater detail, it is necessary to include sites with less contamination: The importance of preliminary surveys in the overall risk management process gives a strong motivation for such an evaluation. Generally, the lack of research and scientific support for the various assessment procedures in use suggests that there is a need for method development, standardization, and validation.  相似文献   

19.
Sustainable use of military training lands requires understanding and prediction of the effects of military vehicles on vegetation. We examined the initial impacts of an 8-wheeled, light armored vehicle (LAV) on grassland vegetation at Fort Lewis, Washington. The LAV drove replicate spiral paths at two starting velocities, 10.3 and 5.1 m s(-1). The disturbed width (width of ground impacted by the tires) increased as turning radius decreased, but was unaffected by vehicle velocity. An inverse-exponential model predicted disturbed width (r(2)=0.68) at all turning radii for both velocities combined. In low-velocity spirals, and for straight tracking (turning radius>40 m) and moderate turns (radius 20-40 m) in high-velocity spirals, all vegetation damage was imprint (plants flattened by wheels). During sharp (radius <20 m), high-velocity turns, most or all of the disturbed width was scraped free of surface vegetation and soil, which was piled to the outside of each tire track. Total plant cover (all species) was not affected by track curvature in low-velocity spirals, but decreased in the order straight tracking>moderate turns>sharp turns in high-velocity spirals. In low-velocity spirals, post-tracking cover of several plant growth forms (non-native species, perennial species, sod-forming grasses) was similar to pre-tracking cover, but in high-velocity spirals, post-tracking cover of these growth forms decreased in the order straight > or =moderate=sharp. Cover of native species and forbs decreased more in high- than in low-velocity spirals, but was unaffected by curvature. Pre- and post-tracking cover of annual species, bunchgrasses, and shrubs was < or =3%. The most severe vegetation damage caused by operation of wheeled LAVs on grasslands is associated with sharp, high-velocity turns.  相似文献   

20.
Two disciplines claim to provide justification of action. Ethics gives you moral reasons to act upon, whereas economics exploits the concept of rationality. The paper discusses two theories of interdisciplinarity of ethics and economics in order to clarify the relationship. The traditional view of a hierarchical ordering of ethics and economics is rejected, and it is claimed that there are substantial economic contributions to ethical justification.  相似文献   

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