交际教学法在大学英语教学中的应用

交际法已经发展成为一种世界规模的外语教学理论和教学方法,成为当今世界各国外语教学界普遍承认和接受的基本原则.通过对交际教学法的进一步研究分析,叙述了什么是交际教学法,阐述了运用交际教学法组织大学英语教学的模式和交际教学法在大学英语教学中的运用,指出教师应充分运用交际教学法的基本原理更好地来提高中国英语教学水平.     

基层环境执法中环境行政强制问题的探讨

环境行政强制包括环境行政强制措施和环境行政强制执行.在基层环境执法实践中,环境行政强制措施尤其是环境行政强制执行存在许多困惑和问题,拓展环境行政强制措施,给予环保部门一定的行政强制执行权是提高基层环境执法效率和遏制环境污染的有效途径.     

高职教育考试方法改革的探索与实践

根据高职教育教学的要求和课程特点,尤其是为适应培养应用型人才的教学模式,打破“高分低能”的现象,充分发挥考试在高职教育中的指导性作用,本文以食品质量与安全专业的课程为例,对考试考核方法的改革进行了探索与实践。高职教育的考试应突出应用能力考核,加强实践技能检验,坚持在实践中学习、在实践中考核,全面推行操作技能考核,施行“考教分离”,考试形式多样化的原则。     

Seasonal variations of monoterpene emissions from Pinus densiflora in East Asia

The emission rates and compositions of monoterpene from Pinus densiflora were investigated in the Gumsung (GM) and Worak (WM) mountains. The standard emission rates (ERs: ERs is the monoterpene emission rate at standard temperature, 30 degrees C) from P. densiflora ranged from 0.817 to 1.704 (mugC/gdw-h). The ERs and beta-values of total monoterpene were measured at the two study sites (GM and WM). In the spring and summer, the ERs were the highest, while relatively low values (<0.058mugC/gdw-h) were measured in the autumn and winter. In GM and WM sites the beta-value obtained for the different seasons ranged from 0.047 to 0.179, with an average of 0.09. The major monoterpene compounds from P. densiflora were alpha-pinene, myrcene, beta-phellandrene, d-limonene and alpha-terpinene. The fractional compositions of individual monoterpene compounds were significantly different between the two test sites in the summer and winter. The ERs of the older group (31-40 years) were higher than those in the younger group (21-30 years). However, the monoterpene compositions were similar between the two age groups.     

应用D412螯合树脂治理含镍电镀废水的研究

本文研究了Ｄ４１２螯合树脂对Ｎｉ（Ⅱ）离子静态和动态的吸收性能,并且研究了使用Ｄ４１２树脂除去和回收电镀废水中镍的最佳条件。     

有机膨润土对苯胺的吸附性能及应用研究

以溴化十六烷基三甲铵为改性剂制备有机膨润土,利用正交实验研究了有机膨润土吸附垃圾渗滤液中极性有机污染物苯胺的性能、条件及改性条件对吸附效果的影响。结果表明,有机改性膨润土对苯胺有很好的吸附效果,实验条件下对苯胺的去除率可达90％以上,绘制了有机膨润土吸附苯胺的吸附等温线,通过与吸附苯酚效果的比较,总结了有机膨润土吸附极性有机污染物的一般规律。     

苯甲酰苯胺类化合物溶解度和分配系数的测定及定量结构—性质相关研究

本文采用摇瓶法测定了１４各甲酰苯胺类化合物的溶解度及正辛醇／水分配系数,二者之间具有较好的相关性,应用线性溶剂化相关方法获得的相关方程,能更好地预测测苯甲酰苯胺类化合物的的水溶解度和正辛醇／水分配系数。     

Migration of natural estrogens around a concentrated dairy-feeding operation

Concentrated animal feeding operations have been recognized as one of the most important contributors of natural estrogens which show significant endocrine-disrupting properties in aquatic environments. In this study, the concentrations of 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), estrone (E1), and estriol (E3) in several matrices, including soils (surface and deep), sediments (surface and deep), and groundwaters, around a typical dairy farm were surveyed using gas chromatography/mass spectrometry. Of the two farmlands, surface and subsurface sediments in waste lagoon and along effluent drainage drench, the concentrations of 17α-E2, 17β-E2, and E1 ranged from below detection limit to the highest level of 6.60 μg/kg, except that E3 was not detectable. Three estrogens of 17α-E2, 17β-E2, and E1 with the concentrations of 3.18-31.61 ng/L were observed in two groundwater samples. The results clearly demonstrated the vertical migration and horizontal transport of estrogens in the investigated area. Within 750-m distance, it was observed the attenuation of 17α-E2, 17β-E2, and E1 along the effluent route and the horizontal migration of estrogens was less than 1,350 m in this survey.     

Chemical compositions and sources of atmospheric PM10 in heating, non-heating and sand periods at a coal-based city in northeastern China

Mass concentrations and chemical components (18 elements, 9 ions, organic carbon [OC] and elemental carbon [EC]) in atmospheric PM(10) were measured at five sites in Fushun during heating, non-heating and sand periods in 2006-2007. PM(10) mass concentrations varied from 62.0 to 226.3 μg m(-3), with 21% of the total samples' mass concentrations exceeding the Chinese national secondary standard value of 150 μg m(-3), mainly concentrated in heating and sand periods. Crustal elements, trace elements, water-soluble ions, OC and EC represented 20-47%, 2-9%, 13-34%, 15-34% and 13-25% of the particulate matter mass concentrations, respectively. OC and crustal elements exhibited the highest mass percentages, at 27-34% and 30-47% during heating and sand period. Local agricultural residuals burning may contribute to EC and ion concentrations, as shown by ion temporal variation and OC and EC correlation analysis. Heavy metals (Cr, Ni, Zn, Cu and Mn) from coal combustion and industrial processes should be paid attention to in heating and sand periods. The anion/cation ratios exhibited their highest values for the background site with the influence of stationary sources on its upper wind direction during the sand period. Secondary organic carbon were 1.6-21.7, 1.5-23.0, 0.4-17.0, 0.2-33.0 and 0.2-21.1 μg m(-3), accounting for 20-77%, 44-88%, 4-77%, 8-69% and 4-73% of OC for the five sampling sites ZQ, DZ, XH, WH and SK, respectively. From the temporal and spatial variation analysis of major species, coal combustion, agricultural residual burning and industrial emission including dust re-suspended from raw material storage piles were important sources for atmospheric PM(10) in Fushun at heating, non-heating and sand periods, respectively. It was confirmed by principal component analysis that coal combustion, vehicle emission, industrial activities, soil dust, cement and construction dust and biomass burning were the main sources for PM(10) in this coal-based city.