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11.
酒精废醪液浓缩法是一种资源化处理技术。将废醪液用石灰乳中和后,经多效蒸发加以浓缩,然后或者直接干燥为干粉,或者与干蔗髓混匀后干燥成蔗髓干粉,或者直接用作复合肥原料。此技术已在广东、广西和云南的部分糖厂使用,均取得较好的环境、社会和经济效益。 相似文献
12.
H. Cuckle N. Wald J. D. Stevenson H. M. May M. A. Ferguson-Smith A. Milford Ward H. M. Barbour K. M. Laurence B. Norgaard-Pedersen 《黑龙江环境通报》1990,10(2):71-77
Data on maternal serum alpha-fetoprotein (AFP) levels at 13–24 weeks' gestation in 46 twin pregnancies with open neural tube defects (22 with anencephaly, 24 with open spina bifida) and 169 unaffected twins were used to estimate the detection and false-positive rates associated with different cut-off levels. Using the conventional cut-off level of 2·5 multiples of the median (MoM) for unaffected singleton pregnancies of the same gestation and laboratory, the detection rate in twins was 99 per cent for anencephaly and 89 per cent for open spina bifida, with a false-positive rate of 30 per cent. Using a 5·0 MoM cut-off level to maintain a similar false-positive rate to that found among singleton pregnancies at 16–18 weeks' gestation (about 3 per cent), the detection rate was 83 per cent for anencephaly and 39 per cent for open spina bifida. Estimates are provided of the odds of having an affected twin pregnancy given a positive AFP result as well as the odds for individual women with a raised AFP level. 相似文献
13.
阐述了人类在不同阶段所面临的不同环境问题和未来新技术革命对环境的可能影响,介绍了环境科学随着环境问题的变化而不断发展变化的过程,指出在新技术革命时代环境科学所面临的未来研究课题及任务。 相似文献
14.
酞酸酯对人与环境的危害 总被引:32,自引:1,他引:32
酞酸酯是一种增塑剂,随着时间的推移,可由塑料中转移到外环境,现已成为地球上最为广泛存在的环境污染物。该文较系统地介绍了酞酸酯的理化性质,毒性和致癌作用,以及其对环境的影响,环境行为,动物的吸收,分布、代谢和排泄等等,最后还对酞酸酯的有关毒性评价作了部分介绍。 相似文献
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16.
采用生态系统健康理论分析开发区生态环境问题具有较强的理论意义和现实意义。着重构建了开发区生态系统健康评价的指标体系和模糊评价模型,提出评价标准。并对苏州高新区生态系统健康进行评价。进而指出制约因子并提出相应的诊断方案,为其优化生态系统结构和完善系统功能提供科学依据。 相似文献
17.
Lee Benda Marwan A. Hassan Michael Church Christine L. May 《Journal of the American Water Resources Association》2005,41(4):835-851
Headwater streams comprise 60 to 80 percent of the cumulative length of river networks. In hilly to mountainous terrain, they reflect a mix of hillslope and channel processes because of their close proximity to sediment source areas. Their morphology is an assemblage of residual soils, landslide deposits, wood, boulders, thin patches of poorly sorted alluvium, and stretches of bedrock. Longitudinal profiles of these channels are strongly influenced by steps created by sediment deposits, large wood, and boulders. Due to the combination of small drainage area, stepped shallow gradient, large roughness elements, and cohesive sediments, headwater streams typically transport little sediment or coarse wood debris by fluvial processes. Consequently, headwaters act as sediment reservoirs for periods spanning decades to centuries. The accumulated sediment and wood may be episodically evacuated by debris flows, debris floods, or gully erosion and transported to larger channels. In mountain environments, these processes deliver significant amounts of materials that form riverine habitats in larger channels. In managed steepland forests, accelerated rates of landslides and debris flows resulting from the harvest of headwater forests have the potential to seriously impact the morphology of headwater streams and downstream resources. 相似文献
18.
ABSTRACTThe present study was carried out to investigate the effect of three organic matters (stalk powder, microbial fertilizer, and manure) on Leymus chinensis germination, growth, and urease activity and available nitrogen (N) in coastal saline soil. The study was conducted in a completely randomized design with eight treatments: J0V0Y0, J1V0Y0, J0V1Y0, J0V0Y1, J1V1Y0, J1V0Y1, J0V1Y1, J1V1Y1. The notations were based on the quantities of each agent added to 1 kg of coastal saline soil: J0 – no straw powder, J1 – 0.2 kg straw powder, Y0 – no manure, Y1 – 0.3 kg manure, V0 – no microbial fertilizer, V1 – 0.2 L microbial fertilizer, each in quantic repeat. L. chinensis was sown as 50 seeds per pot. Results indicated that addition of organic agents exerted a significantly enhanced germination, increase in fresh weight and elevated soil urease activity. Soil available N levels were significantly positively correlated with soil urease activity and fresh weight, but not with germination rate. It is noteworthy that the halophyte L. chinensis showed improved characteristics when grown in coastal saline soil with addition of organic amendments. 相似文献
19.
Mao Guanghua Liu Hongyang Ding Yangyang Zhang Weijie Chen Hui Zhao Ting Feng Weiwei Wu Xiangyang Yang Liuqing 《Environmental science and pollution research international》2020,27(9):9318-9326
Environmental Science and Pollution Research - In this study, the immature mice were taken to assess the potential neurological toxicity of lead (Pb) and di (n-butyl) phthalates (DBP) combination... 相似文献
20.
Bin-Jumah May N. AL-Huqail Arwa Abdulkreem Abdelnaeim Noha Kamel Mohamed Fouda Maged M A Abulmeaty Mahmoud M A Saadeldin Islam M. Abdel-Daim Mohamed M. 《Environmental science and pollution research international》2021,28(21):26653-26663
Environmental Science and Pollution Research - Acrylamide (AA) is a hazardous chemical that is widely used in industrial practices. Spirulina platensis (SP) is a blue green alga that is rich in... 相似文献