Human chorionic β-mannosidase: Comparison with β-mannosidase from human cultured fibroblasts

The conditions for assay of β-mannosidase activity in human chorionic villi (CV) were studied using the fluorogenic substrate 4-methylumbelliferyl-β-D-mannopyranoside. A comparison of the biochemical properties of the CV β-mannosidase with those of the enzyme from human cultured fibroblasts showed their similarity. Like the enzyme from skin fibroblasts, the CV β-mannosidase had rather high activity. Both enzymes had virtually the same pH optimum (4.2-4.7) and K_m value. The data presented suggest that chorion biopsy specimens can be used for prenatal determination of β-mannosidase activity at an early stage of development.     

煤矸石在高速公路建设中利用的环境可行性分析

以平顶山至临汝段高速公路工程建设为例，对煤矸石在公路建设中应用的环境可行性进行了分析论证。     

我国胭脂鱼资源现状及其资源恢复途径的探讨

胭脂鱼为我国特有鱼类 ,已知仅分布于长江和闽江。目前胭脂鱼在长江水系中的资源量明显减少 ,数量已较国家一类水生野生保护动物中华鲟和达氏鲟为少 ;闽江胭脂鱼种群几近绝迹。造成胭脂鱼资源下降的原因主要与其自身繁殖力低 ,发育时间长 ,以及过度捕捞和水域污染等因素有关。人工放流是恢复长江胭脂鱼资源的重要手段。     

复合表面活性剂对燃煤陶瓷窑炉黑烟润湿作用的研究

为了有效控制燃煤陶瓷窑炉黑烟的污染，根据理论和实验研究的结果，选择合适的润湿剂和助剂，研究了阴离子表面活性剂Y1、非离子表面活性剂F1与无机盐Z1复配后溶液表面张力的变化，筛选出了表面张力较小的配比。利用所选配比对燃煤陶瓷窑炉黑烟的润湿作用进行了Walker实验研究和理论分析。实验结果表明，0．5mmol／L Y1＋50mmol／L Z1＋0．03mmol／L F1的配比对黑烟的润湿作用较好。并对其润湿机理进行了探讨。     

土壤资源信息共享的WEBGIS实现

如何使用和共享现有的土壤科学数据一直是一个重要问题。为提高土壤资源信息的共享和利用效率,文章阐述了在因特网环境下实现土壤资源信息发布的体系结构及关键技术,讨论了其实现方法。采用WebGIS技术,以ARCIMS为平台,以广东省土壤系列图件为基础,构建土壤信息共享系统,通过WEBGIS进行土壤资源信息的发布和共享,并介绍了系统的主要功能。     

植物对水溶液中乐果的降解及影响因素分析

通过气相色谱分析,建立浓度换算标准曲线,研究了三种水生植物水葱、香蒲和石菖蒲对水溶液中乐果的降解效果,并进一步探讨了水葱对乐果降解的动力学过程和各因素对乐果去除的贡献。结果表明,三种植物对乐果去除能力由大到小依次为:水葱,香蒲,石菖蒲。水葱10天内对乐果的去除率为58%,香蒲和石菖蒲组对乐果的去除率分别为39%和33%。乐果的自然降解和挥发、植物吸收和微生物降解作用对乐果去除的贡献率约为:20%、40%、30%。水体的pH升高能够加速乐果的降解,营养盐质量浓度的下降不利于植物去除乐果。     

Structural characteristic and ammonium and manganese catalytic activity of two types of filter media in groundwater treatment

Two types of filter media in groundwater treatment were conducted for a comparative study of surface structure and catalytic performance. Natural filter media was adopted from a conventional aeration–filtration groundwater treatment plant, and active filter media as a novel and promising filter media was also adopted. The physicochemical properties of these two kinds of filter media were characterized using numerous analytical techniques,such as X-Ray diffraction(XRD), scanning electron microscope(SEM), energy dispersive X-ray(EDX), X-ray photoelectron spectroscopy(XPS) and Zeta potential. The catalytic activities of these filter media were evaluated for ammonium and manganese oxidation.XRD data showed that both active filter media and natural filter media belonged to birnessite family. A new manganese dioxide(Mn O2) phase(PDF#72-1982) was found in the structure of natural filter media. The SEM micrograph of natural filter media showed honeycomb structures and the active filter media presented plate structures and consisted of stacked particle. These natural filter media presented lower level of some trace elements such as calcium and magnesium, lower degree of crystallinity, lower Mn(III) content and lattice oxygen content than that of active filter media, which were associated with its poor ammonium and manganese catalytic activities. In addition, some γ-Fe2 O3 and Mn CO3 were found in the coating which may hinder the ammonium and manganese catalytic oxidation. This study provides a thorough and comprehensive understanding about the most commonly used filter media in water treatment, which can provide a theoretical guide to practical applications.