热压机防火问题探讨

针对企业在热压机防火 方面的薄弱环节，具体分析着火原因，从多方面提出了防范措施。     

固定化微生物制备技术及生物脱氮研究

利用载体经干燥后机械强度得到提高的特性,建立一种低胶体浓度固定化微生物制备技术:包埋剂为5.5%PVA、0.45%SA,固定液为饱和硼酸与0.6%硫酸铝的混合液,包菌量为0.4g/mL包埋剂。小球硬化24 h后洗净并放入30℃鼓风干燥箱干燥3.5 h后备用。制备出的固定化微生物氨氧化速率为24.3 mg/(L·h),相对活性为77.7%。     

黄河水质监测的分析方法研究

随着对黄河水的治理工作的逐渐深入,关于黄河水质的监测事业都取得了快速的发展并有着不小的进步,当然仍然存在着一些问题,比如监测的条件较为单一且技术落后、监测的断面也不够多、资料信息缺乏等.随着时代的发展,现有的一些关于水质监测的方法已经不能满足监测的要求,所以本文对于黄河水质监测的分析方法做了一定得研究,希望对于水质监测方面有一定的帮助.     

Characterization of heavy metal desorption from road-deposited sediment under acid rain scenarios

Road-deposited sediments(RDS) on urban impervious surfaces are important carriers of heavy metals.Dissolved heavy metals that come from RDS influenced by acid rain,are more harmful to urban receiving water than particulate parts.RDS and its associated heavy metals were investigated at typical functional areas,including industrial,commercial and residential sites,in Guangdong,Southern China,which was an acid rain sensitive area.Total and dissolved heavy metals in five particle size fractions were analyzed using a shaking method under acid rain scenarios.Investigated heavy metals showed no difference in the proportion of dissolved fraction in the solution under different acid rain pHs above3.0,regardless of land use.Dissolved loading of heavy metals related to organic carbon content were different in runoff from main traffic roads of three land use types.Coarse particles(150 μm) that could be efficiently removed by conventional street sweepers,accounted for 55.1%-47.1%of the total dissolved metal loading in runoff with pH 3.0-5.6.The obtained findings provided a significant scientific basis to understand heavy metal release and influence of RDS grain-size distribution and land use in dissolved heavy metal pollution affected by acid rain.     

分子印迹技术在环境痕量有机物中的应用

分子印迹技术（MolecularImprintingTechnique,NIT）是一种新型的识别技术,其核心是制备对目标分子具有高度识别的分子印迹聚合物（MolecularlyImprintedPolymers,MIPs）。MIPs具有特异选择性、稳定性等特点,为分离和去除环境中的痕量有机物提供有效的途径。文章综述了MIT在痕量环境有机物的分析、检测和处理中的研究进展,并对存在的问题进行了探讨。     

超细水雾抑制酒精火有效性实验研究

为了研究超细水雾对酒精火的抑制效果,通过搭建超细水雾抑制受限空间酒清火燃烧的小尺寸实验平台,利用基于质量损失速率的热释放速率计算方法,研究超细水雾与酒精火焰相互作用时,酒精火火焰的变化规律及酒精火的热释放速率,与此同时,采用高速摄像仪对火焰进行拍摄,利用Matlab图像处理程序对采集的火焰图片剖面进行处理.研究发现:施...     

建筑行业职业工装的应用设计

本文通过对建筑行业工作特点及其安全性的要求分析,研究建筑行业职业工装的款式结构、服装安全色彩的选择以及服装加工过程中的规范,对建筑行业职业工装提出了具体的设计方法,总结出了较系统的思路,以期为建筑行业安全生产提供必要的保障。     

新一代更安全婴儿床标准——美国消费品安全委员会对标准实旋相关闻题解答

本文主要介绍新婴儿床标准的内容和要求,以及美国消费品安全委员对消费者、儿童保育中心、医院、生产商、进口商和零售商所关心的问题的解答。     

Natural attenuation of arsenic in the wetland system around abandoned mining area

Mechanisms of natural attenuation of arsenic (As) by wetland plants may be classified by plant uptake and adsorption and/or co-precipitation by iron (oxy)hydroxide formed on the root surface of plants or in rhizosediment. A natural Cattail (Typha spp.) wetland impacted by tailings containing high levels of As from the Myungbong abandoned Au Mine, South Korea was selected, and the practical capability of this wetland to attenuate As was evaluated. The As concentrations in the plant tissues from the study wetland were several-fold higher than those from control wetland. SEM-EDX analyses demonstrated that iron plaques exist on the rhizome surface. Moreover, relatively high As contents bonded with hydrous iron oxides were found in the rhizosediments rather than in the bulk sediments. It was revealed through the leaching and sequential extraction analyses that As existed as more stable forms in the wetland sediment compared with adjacent paddy soil, which is also contaminated with As due to input of mine tailings. The As concentration ratios of extracted solution to sediment/soil represented that the wetland sediment showed significant lower values (10-fold) rather than the paddy soil with indicating high As stability. Also, As in the wetland sediment was predominantly bonded with residual phases on the basis of results from sequential extraction analysis. From these results, it is concluded that transformation of As contaminated agricultural field to wetland environment may be helpful for natural attenuation until active remediation action.     

Integrative trophic network assessments of a lentic ecosystem by key ecological approaches of water chemistry, trophic guilds, and ecosystem health assessments along with an ECOPATH model

The objective of this study was to describe the trophic structure and energy flow in a lentic ecosystem in South Korea. Physicochemical water conditions were evaluated along with the reservoir ecosystem health using a multimetric IBI model. Nutrient analyses of the reservoir showed a nutrient rich and hypereutrophic system. Guild analysis revealed that tolerant and omnivorous species dominated the ecosystem. Tolerant fish, as a proportion of the number of individuals, were associated (R² > 0.90, p < 0.01) with TN and TP, the key indicators of trophic state in lentic ecosystems. The mean Reservoir Ecosystem Health Assessment (REHA) score was 19.3 during the study, which was judged as in ‘fair to poor’ condition. A trophic analysis of the reservoir estimated by the ECOPATH model shows that most activity in terms of energy flow occurred in the lower part of the trophic web, where there was intensive use of primary producers as a food source. Consequently, of the 10 consumer groups, nine fell within trophic levels <2.8. Trophic levels (TL) estimated from the weighted average of prey trophic levels varied from 1.0 for phytoplankton, macrophytes, and detritus to 3.25 for the top predator, Pseudobagrus fulvidraco. Our integrated approach to trophic network analysis may provide a key tool for determining the effects of nutrient influx on energy flow pathways in lentic ecosystems.