多功能膨胀渗透仪的研制及压实膨润土的渗透性试验

报道多功能膨胀渗透仪的研制及压实膨润土的渗透测试结果。该装置可用于土壤的固结、渗透、膨胀等实验,具有一物多用的特点,特别适合于难渗透的高压实膨润的研究。     

Mine rescuers’ heat load during the expenditure of physical effort in a hot environment,using ventilated underwear and selected breathing apparatus

Mine rescuers’ heat load under the same physical effort load (25% of the maximal oxygen uptake), using three types of breathing apparatus, in newly developed heat-removing underwear and outerwear was assessed for typical work conditions of mine rescuers, under milder and harsher ambient conditions of 32 and 38?°C, respectively, both at relative humidity of 85% and air velocity of 1.0?m/s. Expending physical effort at the same load while using different kinds of breathing apparatus resulted in a similar heat load. Under both milder and harsher ambient conditions, heat storage and sweating intensity were greater than the average limit value recommended by hygienic standards, which indicates that the use of breathing apparatus significantly hinders heat exchange with the environment. The developed clothing for mine rescuers was highly rated, and was considered by most people to be better than that used currently.     

危险废物回转式流化冷渣多段焚烧系统焚烧特性研究

危险废物的处理和处置是摆在我国各级市政府面前的紧迫任务。然而我国已经运行的危险废物焚烧装置普遍存在回转窑挂壁结渣、热灼减率偏高和污染排放超标等问题,作者通过将回转窑和流化床特点相结合的方法提出了一种新型危险废物回转式流化冷渣多段焚烧处置装置。该装置采用回转窑(一燃室)、二燃室和流化床结合的热解-流化焚烧工艺,特别是采用控制窑头温度避免了回转窑挂壁结渣;采用流化冷渣装置延长未燃烬渣的焚烧时间,解决了热灼减率偏高问题;水冷式烟气急冷装置可以将烟气温度从1 100℃降到200℃,防止了二恶英的尾部低温再生成。该系统运行稳定可靠,可以处理医疗垃圾和大多数的固态和液态危险废物,实现了烟气污染物尤其是二恶英排放达到国家标准的目标。同时对该系统运行时窑头温度分布、二燃室炉膛出口氧量变化、回转窑和炉膛升温特性、燃烧室外壁温度分布等几方面运行数据都进行了详细的介绍,为危险废物焚烧炉的运行提供了宝贵的经验数据。     

转鼓铁碳微电解法预处理液晶废水

采用转鼓铁碳微电解法预处理液晶生产废水,优化了工艺参数,并进行了装置连续运行试验。结果表明：保持转鼓转速2 r/min,在废水pH=2.0、铁碳比（m（铸铁屑）∶m（活性炭））1∶1.5、填料装填率（填料体积与反应器有效容积之比）1∶10、HRT=3 h的优化工艺条件下,废水BOD₅/COD由处理前的0.181提高到0.265;电解装置连续运行30 d,COD去除率稳定在40.1%~43.2%之间,且填料未出现板结现象。     

DDT residue contamination in sediments from Lake Sibaya in northern KwaZulu-Natal,South Africa: Implications for conservation in a World Heritage Site

Maputaland in northern KwaZulu-Natal is a biodiversity hotspot and host to a number of ecologically important systems, including Lake Sibaya, southern Africa’s largest natural freshwater lake. The region is malaria endemic and this study reports the presence of DDT and its metabolites in the sediments of Lake Sibaya that have resulted from the widespread and continued use of DDT in the region. DDT residues (p,p′-DDT, p,p′-DDD, and p,p′-DDE) were detected at all 11 sites sampled, with total concentrations ranging from 0.8 to 123 ng g⁻¹. Total DDT concentrations at Lake Sibaya represent some of the highest levels reported in South Africa, with most samples exceeding sediment quality guideline values. The findings from this study raise concerns and indicate that urgent further work is needed to investigate the potential for bioaccumulation, which could adversely affect breeding fish, bird, and crocodile populations in the region. While this study represents the first report on DDT contamination in Lake Sibaya, results have important implications for a number of other aquatic ecosystems within the Maputaland ecoregion, as well as the many local people who depend on them.     

Urinary dialkyl phosphate levels before and after first season chlorpyrifos spraying amongst farm workers in the Western Cape,South Africa

The study investigated urinary levels of dialkyl phosphates resulting from pesticide exposure amongst 40 farm workers. Workers were tested (urinary dialkyl phosphate levels, anthropometry, short exposure questionnaire) before and after the first day of seasonal chlorpyrifos spraying. Median baseline urinary dialkyl phosphates was high amongst both non-applicators (1587.5 μg/g creatinine, n = 8) and applicators (365.6 μg/g creatinine, n = 9). There was not much evidence of an increase in post-spray dialkyl phosphates levels from pre-spray levels amongst both applicators and non-applicators. Hours mixing, spraying, driving a tractor and hours worked by non-applicators were not significantly associated with an increase in post-spray dialkyl phosphate levels, adjusting for age, height, weight, gender, use of empty pesticide containers and self-reported kidney problems. Past applicator status was weakly positively associated with pre-spray dialkyl phosphate levels adjusting for age, height, weight, and gender, self-reported kidney problems, smoking and alcohol (β= 1019.5, p = 0.307, R²= 0.28). The high dialkyl phosphate levels call for an epidemiological investigation into the health effects of organophosphorous pesticides.     

滚筒式生物反应器的设计及应力分析

针对城市生活垃圾好氧堆肥的处理工艺,设计一种用于好氧堆肥的滚筒式生物反应器。滚筒式生物反应器的设计主要包括主体结构设计,及反应器主体结构强度模拟分析。应用赫兹接触理论对支承装置中滚圈与托轮之间的接触应力进行计算。同时,结合ANSYS中不分离的接触方式模拟分析支承装置的接触应力,得出支承装置接触应力的分布规律,并将理论计算结果与ANSYS模拟结果进行对比。     

Weed Seedbank Evaluating Method to Generate Spatial Distribution Maps

Abstract

The objective of this work was to develop a fast and practical method of weed seedbank evaluation to generate spatially distributed maps for use in site-specific weed management. Soil cores were collected at 0.20 m depth, air-dried, and then submitted to seedling growth in greenhouse. The sampling grid of 20 by 20 m was georeferenced by Global Positioning System, obtaining 73 soil cores with three replicates. During the greenhouse trial, there were two peaks of weed seedling growth: one in 119 days after water irrigation and another after KNO₃ application. Weeds seedbank maps were obtained at different stages of seedling growth. The Pearson correlation was 0.99 for Brachiaria plantaginea seedbank map, 0.95 for Commelina benghalensis, and 0.85 for Cyperus rotudus generated at 119 days compared with 392 days after seedling growth in the greenhouse. The Brachiaria plantaginea seedbank map evaluated at 35 days presented correlation of 0.97 with 392 days. It was concluded that, for site-specific weed seedbank management, the evaluation of seedling growth in greenhouse until the first emergence peak is enough to generate weed seedbank maps.     

医疗废物回转窑焚烧线中二恶英的生成

通过采集医疗废物回转窑焚烧生产线不同部位的烟气的二恶英样品,研究了医废焚烧过程二恶英在焚烧线200～600℃区间不同烟道断面烟气中分布变化情况。研究结果表明,医疗废物焚烧后烟气中二恶英的发生浓度要高于一般的生活垃圾焚烧烟气的浓度,大致在5～23.3 ng TEQ/m3的范围,锅炉出口到脱酸塔入口段的管道和设备为烟气中二恶英重新合成的高发区域,医废焚烧烟气中二恶英(TEQ)主要是以气态污染物的形态存在。     

弧叶型旋转窑烧制污泥陶粒实验研究

实验选取污水污泥、粉煤灰和港口淤泥为原辅材料,采取正交实验设计物料质量配合比与烧制工艺参数,遴选出最佳物料配比和优化的烧制工艺;依照选定物料配比和工艺参数采用弧叶型旋转窑烧制污泥陶粒并测定产品的1 h吸水率,软化系数,堆积密度,表观密度,颗粒级配,粒型系数以及产品浸出毒性等技术指标,选取制得陶粒产品替代全部天然石料配制...