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91.
小型炭素焙烧炉沥青烟气净化技术初探   总被引:5,自引:2,他引:5  
阐述了颗粒层吸附技术在小型炭素焙烧沥青烟气净化中的应用。  相似文献   
92.
采用溶胶-凝胶法,在瓷砖釉面上制备了良好光催化活性TiO2薄层材料,研究结果表明瓷砖釉面TiO2薄层材料对甲基橙的光催化反应遵循一级动力学规律,光催化降解率与液层厚度符合指数关系。在太阳光照射下,釉面瓷砖TiO2薄层材料能对甲基橙有效地降解。  相似文献   
93.
Subsidence is a primary factor governing marsh deterioration in Mississippi River deltaic plain coastal marshes. Marsh surface-water level relationships are maintained primarily through soil organic matter accumulation and inorganic sediment input. In this study we examined the role of soil organic matter accumulation in maintaining marsh elevation in a brackish Spartina patens marsh. Measured rates of soil organic accumulation were compared to plant biomass production and soil respiration (carbon dioxide and methane emission) at the study sites. The study demonstrated the importance of plant biomass production to soil organic carbon accumulation in maintaining viable Spartina patens marshes in sediment-deficient coastal environments. The role of Mississippi River freshwater reintroduction in maintaining conditions for organic accretion is discussed.  相似文献   
94.
ABSTRACT: Ground water contamination by excess nitrate leaching in row‐crop fields is an important issue in intensive agricultural areas of the United States and abroad. Giant cane and forest riparian buffer zones were monitored to determine each cover type's ability to reduce ground water nitrate concentrations. Ground water was sampled at varying distances from the field edge to determine an effective width for maximum nitrate attenuation. Ground water samples were analyzed for nitrate concentrations as well as chloride concentrations, which were used as a conservative ion to assess dilution or concentration effects within the riparian zone. Significant nitrate reductions occurred in both the cane and the forest riparian buffer zones within the first 3.3 m, a relatively narrow width. In this first 3.3 m, the cane and forest buffer reduced ground water nitrate levels by 90 percent and 61 percent, respectively. Approximately 40 percent of the observed 99 percent nitrate reduction over the 10 m cane buffer could be attributed to dilution by upwelling ground water. Neither ground water dilution nor concentration was observed in the forest buffer. The ground water nitrate attenuation capabilities of the cane and forest riparian zones were not statistically different. During the spring, both plant assimilation and denitrification were probably important nitrate loss mechanisms, while in the summer nitrate was more likely lost via denitrification since the water table dropped below the rooting zone.  相似文献   
95.
活性污泥吸附重金属Cr6+的研究   总被引:8,自引:0,他引:8  
以活性污泥为材料,采用不同时间、温度、pH进行吸附重金属Cr^6 的研究。实验结果表明,当吸附时间为15min,吸附温度为28℃,吸附pH=7时具有较好吸附效果。在此条件下,当重金属Cr^6 浓度为50mg/L,其吸附率可达97.2%。  相似文献   
96.
范广裕 《化工环保》1996,16(3):156-161
以球形活性炭为吸附剂,用吸附法处理黑索金(RDX)废水,出水能够达到国家排放标准,球形活性炭的动态饱和吸附量为0.123-0.140g/g,吸附带长为2m。吸附饱和的球形活性炭,可用碱液以复再生。笔者还提出了数学模型,导出了处理实验数据公式,此公式可推广应用于同类吸附实验数据处理。  相似文献   
97.
闫光绪  张洪林 《化工环保》1996,16(5):263-268
对抚顺石化公司化工塑料厂苯乙烯废水活性炭吸附装置的预处理设施、活性炭吸附及再生性能进行了评价,分析了出水水质超标的主要原因,用混凝沉淀-砂滤流程改进了原处理工艺,使出水水质得到了显著改善。  相似文献   
98.
Starch-PVOH cast films were prepared with and without crosslinking agent (hexamethoxymethylmelamine) in the absence of plasticizer. Moisture absorption in films without crosslinking agent at a low relative humidity was similar to that of PVOH and increased as the relative humidity increased. Films with crosslinking agent showed moisture absorption linearly proportional to the relative humidity. Significant improvement in resistance to water disintegration for crosslinked starch-PVOH films was observed. While the tensile strength decreased with increased relative humidity, crosslinking significantly improved the tensile strength. Increased PVOH content improved elongation of films even when the relative humidity was 80% or higher. Biodegradation studies revealed that the degradation rate was negatively correlated with the PVOH content in films and crosslinking generated more converged degradation curves. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.  相似文献   
99.
活性炭膜处理工业废水的试验研究   总被引:2,自引:0,他引:2  
将活性炭膜与常规弹性材料同时作为生物接触氧化处理工艺的填料,分别加装在相同条件的两套接触氧化池中,采用生物接触氧化处理工艺,在同样的条件下处理工业废水,经过对试验数据的对比分析得出:以活性炭膜为填料,处理废水的能力更强,净化效果更好。  相似文献   
100.
低温烟气脱氮活性炭基催化剂   总被引:3,自引:0,他引:3  
梁锦平  华坚  尹华强  刘中正 《四川环境》2006,25(2):99-104,110
活性炭基催化剂是低温烟气脱氮的优良催化剂。本文探讨了活性炭基催化荆的低温脱氮机理,分析了催化荆性能的影响因素,比较了各种催化荆的脱氮机理和性能,在此基础上指出了今后的研究方向。  相似文献   
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