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311.
邓安 《环境工程学报》2009,3(11):1931-1937
废铸砂是铸造工业在金属制品的生产过程中次生出来的一种细颗粒固体废弃物。研究其作为一种资源进行合理再利用是当前处置废铸砂、保护生态环境的良好对策。本文对废铸砂的环境特征、物理性质及废铸砂作为建筑材料在多种建筑制品及工程中的资源化再利用进行了综述研究,涉及的再利用领域包括混凝土、热拌沥青混合料、低强度填料、水泥、路基、路堤、阻水帷幕(屏障)和衬垫。调查发现,次生于黑色金属(铁和钢)铸造生产线的废铸砂是一种无害固体废弃物,正确处置和科学利用,对环境不会产生二次污染,在以上建筑制品及工程中的应用能满足相关技术、性能要求,可以替代相关的材料进行资源化再利用。  相似文献   
312.
四川旱涝灾害时间分布序列的分形特征研究   总被引:12,自引:2,他引:12  
李祚泳  邓新民 《灾害学》1994,9(3):88-90,66
本文采用分形理论计算了四川旱涝灾害时间分布序列的分数维,其结果初步证实了四川旱涝灾害时间分布在一定区间范围内的无标度性。无标度区的跨度及相应的分形维数可作为四川旱涝灾害自组织程度的量度。  相似文献   
313.

CoFe2O4/ordered mesoporous carbon (OMC) nanocomposites were synthesized and tested as heterogeneous peroxymonosulfate (PMS) activator for the removal of rhodamine B. Characterization confirmed that CoFe2O4 nanoparticles were tightly bonded to OMC, and the hybrid catalyst possessed high surface area, pore volume, and superparamagnetism. Oxidation experiments demonstrated that CoFe2O4/OMC nanocomposites displayed favorable catalytic activity in PMS solution and rhodamine B degradation could be well described by pseudo-first-order kinetic model. Sulfate radicals (SO4 ·) were verified as the primary reactive species which was responsible for the decomposition of rhodamine B. The optimum loading ratio of CoFe2O4 and OMC was determined to be 5:1. Under optimum operational condition (catalyst dosage 0.05 g/L, PMS concentration 1.5 mM, pH 7.0, and 25 °C), CoFe2O4/OMC-activated peroxymonosulfate system could achieve almost complete decolorization of 100 mg/L rhodamine B within 60 min. The enhanced catalytic activity of CoFe2O4/OMC nanocomposites compared to that of CoFe2O4 nanoparticles could be attributable to the increased adsorption capacity and accelerated redox cycles between Co(III)/Co(II) and Fe(III)/Fe(II).

  相似文献   
314.
龙口市海水入侵动态系统分析与防治对策   总被引:2,自引:0,他引:2  
海水入侵已成为全球普遍关注的地下水环境问题,它不仅严重地威胁着人类淡水资源,而且破坏生态环境平衡,制约着社会经济可持续发展。以山东省龙口市为靶区,通过分析研究衡量海水入侵重要因子-氯离子浓度时空分布规律及其影响因素,探索海水入侵动态系统规律,提出防治海水入侵的措施和对策。  相似文献   
315.
螺旋藻的应用价值及环境保护功能   总被引:8,自引:0,他引:8  
本文综述了螺旋藻的基本特性,营养价值,药用价值及开发利用现状,着重讨论了螺旋藻的能源价值和在环境污染净化中的作用,展望了应用发展前景。  相似文献   
316.
天然沸石具有较大的孔隙率和比表面积,对氨氮有较强的选择性离子交换能力.运用天然沸石曝气生物滤池处理城市污水厂二级生化出水,结果表明,曝气生物滤池有良好的去除效果.在气水比为3∶1,水力负荷为1 m/h,温度>20℃情况下,沸石曝气生物滤池对城市污水厂二级生化出水COD去除率为12.7%,NH3-N去除率为96.6%;试验系统沿程微生物活性和微生物量呈现逐渐下降趋势,而单位生物量的生物活性沿程分布则与此相反;曝气生物滤池对水中污染物的去除主要集中在底部进水端部分,当水流达到距进水端上方105 cm时,曝气生物滤池对水中NH3-N的去除率已达86.8%(占氨氮总去除率的90%),COD的去除率为13.3%(占COD总去除率的67%).  相似文献   
317.
Deng  Yan-Ling  Yang  Pan  Wang  Yi-Xin  Liu  Chong  Luo  Qiong  Shi  Tian  Zeng  Jia-Yue  Lu  Ting-Ting  Chen  Pan-Pan  Miao  Yu  Zhang  Min  Cui  Fei-Peng  Lu  Wen-Qing  Zeng  Qiang 《Environmental science and pollution research international》2022,29(54):81749-81759
Environmental Science and Pollution Research - Previous studies have reported that exposure to phthalates and polycyclic aromatic hydrocarbons (PAHs) is individually associated with altered semen...  相似文献   
318.
Fertility of lateral spikelets determines the two-rowed or six-rowed spikes of barley (Hordeum vulgare L.), which results in significantly different grain yields. The change in row type from two-rowed to six-rowed shows remarkable domestication characteristics. The Qinghai-Tibet plateau has abundant resources of wild and cultivated barley, and is considered one of the centers of domestication and genetic diversity of cultivated barley. In order to obtain a primary understanding of the genetic basis of lateral spike development regulation and the domestication process in cultivated Tibetan barley, an F2 segregation population was constructed by crossing the two-rowed wild barley accession ZYM0083 with the six-rowed landraces Linzhiheiliuleng. Genetic analysis showed that the row type was controlled by a single gene. Using the specific-locus amplified fragment sequencing (SLAF-seq) technology and bulked segregant analysis (BSA), two DNA pools from 22 two-rowed spike individuals and 22 six-rowed spike individuals of the F2 population were constructed and sequenced. A total of 456 691 SLAF tags were obtained. By adopting the ED and SNP index for association analysis, three candidate regions with a 53.84-Mb interval and containing 536 genes were obtained. Four-hundred thirteen, 189, and 160 annotated genes were acquired by GO, KEGG, and COG libraries, respectively. Loci that control lateral spike development in Tibetan barley were primarily mapped by SLAF-seq, and the results presented in this study will facilitate the fine mapping and cloning of target genes. © 2018 Science Press. All rights reserved.  相似文献   
319.
The ethnic communities of Lugu Lake have experienced the rapid development of tourism because of the attractions of their culture and traditional customs as well as their beautiful environment. Tourism and other economic activities have a variety of socio-cultural effects on host communities. Based on a survey of 105 Mosuo families, statistic correlation analysis was used to examine the local people's viewpoints regarding marriage, language, traditional dress, diet, and factors which could lead to changes in people's opinions. The results show that although Mosuo people are more open to the outside world, Axia relationships and matrilineal families still dominate their life. More than 50% of interviewees have Axia relationships and live in matrilinear families. Tourism income, education and age are three important factors that impact on local people's viewpoints regarding their culture and life. People who are more educated and earn more money from tourism prefer traditional culture and customs. The younger generation is more likely to be affected by tourism because they have contact with the outside world more often in their everyday life. Further research is needed on how to protect the local culture from the boom in tourism, as well as how to minimise its influence on local residents.  相似文献   
320.
交联菌丝体吸附剂的制备及其对Cr^3+的吸附特性   总被引:1,自引:0,他引:1  
深入研究了交联菌丝体吸附剂的制备工艺及其对Cr^3+的吸附特性。交联菌丝体吸附剂制备工艺简单,但在制备过程中,活化剂NaOH和交联剂的用量对吸附特性影响较大。与纯菌丝体吸附剂相比,交联菌丝体吸附剂表观吸附容量提高48%,达到49.83mg/g(pH=2.53,水溶液中的Cr^3+浓度为600mg/L),同时其机械强度明显增强。交联菌丝体吸附剂对Cr^3+的吸附特点是将沉淀法与吸附法相结合,将沉淀与吸附两过程合二为一,从而简化了处理工艺,降低了处理成本。  相似文献   
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