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991.
礼仪是一种文化,也是一种艺术.面对社会对高职学生素质问题的指责,面对高职院校教师对学生素质现状的忧虑,要充分发挥礼仪在推行素质教育中的桥梁作用.在高职院校实施礼仪教育可以从两个方面进行:一是重视礼仪的学习,挖掘礼仪的魅力;二是根据高职学生的特点,改革礼仪教学.  相似文献   
992.
ABSTRACT: The potential for detecting the concentration and type of soils suspended in surface water through remote sensing techniques was investigated by studying the spectral reflectance of two types of soils in suspension. In a large tank filled with 7510 liters of water, 20 levels of suspended sediment (soil) concentration (SSC), ranging from 50 to 1000 mg/l were prepared. A high resolution spectroradiometer was used to measure the reflectance at each SSC level. The reflectance spectra of two contrasting soils were distinct in the visible and near infrared (NIR) portions of the electromagnetic spectrum. The wavelength range between 580–690 nm (visible) was found to be optimal for indicating the type of soil, whereas, the wavelength range between 714–880 (NIR) was found to be appropriate for estimating the concentration of sediment suspended in surface waters.  相似文献   
993.
Structure design of a photosynthetic-based biofuel cell and the fabrication processes to make it have been explored and developed. Novel nanostructure and modified polyaniline have been used to enhance the performance of the biofuel cell. The mechanism of the electron transfer process and the electrocatalysis of polyaniline have been investigated. Photosynthetic-based biofuel cells with a mA/cm2 current density have been demonstrated.  相似文献   
994.
This study aims to identify key environmental risk sources contributing to water eutrophication and to suggest certain risk management strategies for rural areas. The multi-angle indicators included in the risk source assessment system were non-point source pollution, deficient waste treatment, and public awareness of environmental risk, which combined psychometric paradigm methods, the contingent valuation method, and personal interviews to describe the environmental sensitivity of local residents. Total risk values of different villages near Taihu Lake were calculated in the case study, which resulted in a geographic risk map showing which village was the critical risk source of Taihu eutrophication. The increased application of phosphorus (P) and nitrogen (N), loss vulnerability of pollutant, and a lack of environmental risk awareness led to more serious non-point pollution, especially in rural China. Interesting results revealed by the quotient between the scores of objective risk sources and subjective risk sources showed what should be improved for each study village. More environmental investments, control of agricultural activities, and promotion of environmental education are critical considerations for rural environmental management. These findings are helpful for developing targeted and effective risk management strategies in rural areas.  相似文献   
995.
川西地区压裂返排液破胶处理工艺研究   总被引:1,自引:0,他引:1  
吕宝  王晗  彭波 《四川环境》2013,32(2):118-121
油田压裂返排液是油气田开发中产生的一种复杂的多项分散稳定体系,需进行破胶预处理后才能进行下一步处理。文章以川西地区压裂返排液为研究对象,选用次氯酸钠(NaCIO)、过氧化氢(H2O3)、高锰酸钾(KMnO4)为破胶剂进行化氧化破胶剂实验研究,结果表明:高锰酸钾(KMnO4)的破胶效果最好,工艺条件简单,运输、保存方便。COD去除率达77%以上,破胶后水色最好。  相似文献   
996.
Using SPOT/VGT NDVI time series images (2002–2009) and MODIS/LST images (2002–2009) smoothed by a Savitzky–Golay filter, the land surface phenology (LSP) and land surface temperature (LST), respectively, are extracted for six cities in the Yangtze River Delta, China, including Shanghai, Hangzhou, Nanjing, Changzhou, Wuxi, and Suzhou. The trends of the averaged LSP and LST are analyzed, and the relationship between these values is revealed along the urban–rural gradient. The results show that urbanization advances the start of the growing season, postpones the end of the growing season, prolongs the growing season length (GSL), and reduces the difference between maximal NDVI and minimal NDVI in a year (NDVIamp). More obvious changes occur in surface vegetation phenology as the urbanized area is approached. The LST drops monotonously and logarithmically along the urban–rural gradient. Urbanization generally affects the LSP of the surrounding vegetation within 6 km to the urban edge. Except for GSL, the difference in the LSP between urban and rural areas has a significant logarithmic relationship with the distance to the urban edge. In addition, there is a very strong linear relationship between the LSP and the LST along the urban–rural gradient, especially within 6 km to the urban edge. The correlations between LSP and gross domestic product and population density reveal that human activities have considerable influence on the land surface vegetation growth.  相似文献   
997.
本文从营销管理信息系统的构成、营销管理信息系统与企业营销过程的关系、营销管理信息系统的作用、内部记录系统、营销决策支持系统等几个方面对企业的营销管理信息系统进行了浅显的讨论。  相似文献   
998.
The Horqin sandy rangeland of northern China is a seriously desertified region with a fragile ecology. The sandy alluvial and aeolian sediments have a coarse texture and loose structure and are therefore vulnerable to damage caused by grazing animals and wind erosion. We investigated whether grazing exclusion could enhance ecosystem carbon (C) and nitrogen (N) storage and thereby improve overall soil quality. We compared soil properties, C and N storage in biomass (aboveground and below-ground), and the total and light fraction soil organic matter between adjacent areas with continuous grazing and a 12-year grazing exclosure. The soil silt?+?clay content, organic C, total Kjeldahl N, available N and K, and cation-exchange capacity were significantly (P?相似文献   
999.
以二甲胺、氯丙烯等为原料合成二甲基二烯丙基氯化铵(DMDAAC),再与丙烯酰胺(AM)共聚生成共聚物。利用胶体滴定法测定共聚物的阳离子度、一点法测定特性粘数,并利用充气浮选法对阳离子共聚物进行浮选效果评价。结果表明,当产品的阳离子度在30%~40%的范围内除油效果最好,其效果明显优于阳离子聚丙烯酰胺(CPAM),与复配的聚合铝加聚丙烯酰胺(PAC+PAM)相当。  相似文献   
1000.
以黑龙江垦区八五七农场小城镇建设为出发点,分析了八五七农场在小城镇建设中生态环境保护的实践经验,从环境规划、环保基础设施建设、污染防控、环境教育和环境监督管理方面,提出了小城镇建设中应注意的生态环境保护问题及建议。  相似文献   
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