四川省珙县地质灾害特征及其防治措施分析

本文从珙县地质灾害的分布特征、影响因素、防治措施等方面作了较为深入的分析和探讨，以期对地质灾害区划和防治有所借鉴和参考。     

The influence of degree of substitution on blend miscibility and biodegradation of cellulose acetate blends

In this account, we report our findings on blends of cellulose acetate having a degree of substitution (DS) of 2.49 (CA2.5) with a cellulose acetate having a DS of 2.06 (CA2.0). This blend system was examined over the composition range of 0–100% CA2.0 employing both solvent casting of films (no plasticizer) and thermal processing (melt-compressed films and injection molding) using poly(ethylene glycol) as a common plasticizer. All thermally processed blends were optically clear and showed no loss in optical quality after storage for several months. Thermal analysis and measurement of physical properties indicate that blends in the middle composition range are partially miscible, while those at the ends of the composition range are miscible. We suggest that the miscibility of these cellulose acetate blends is influenced primarily by the monomer composition of the copolymers. Bench-scale simulated municipal composting confirmed the biodestructability of these blends and indicated that incorporation of a plasticizer accelerated the composting rates of the blends.In vitro aerobic biodegradation testing involving radiochemical labeling conclusively demonstrated that both the lower DS CA2.0 and the plasticizer significantly enhanced the biodegradation of the more highly substituted CA2.5.While this work was in progress, Robert Gardner was struck with cancer and died on June 6, 1995. This paper is dedicated to his memory and to his contributions as a friend and colleague.     

钻井液化学剂可生物降解性评定方法

介绍研究钻井液化学剂生物降解性的必要性及开发可生物降解钻井液的进展。阐述了常用的评定有机物生物降解性的试验方法。推荐采用BOD_5／COD_Cr比值来评定我国石油行业钻井液化学剂及油田化学剂的可生物降解性，规范石油行业生物降解研究工作，保证评定结果的可靠性和可比性。     

钻井液化学剂可生物降解性研究

实验测定了16种钻井液化学剂的BOD_5和COD_cr，并计算其BOD_5／COD_cr比值。提出了以BOD_5／COD_cr的比值划分钻井液化学剂可生物降解性的分级标准，并对16种钻井液化学剂的可生物降解性进行分级，为其应用提供依据。     

Starch- polyvinyl alcohol crosslinked film— performance and biodegradation

Starch-PVOH cast films were prepared with and without crosslinking agent (hexamethoxymethylmelamine) in the absence of plasticizer. Moisture absorption in films without crosslinking agent at a low relative humidity was similar to that of PVOH and increased as the relative humidity increased. Films with crosslinking agent showed moisture absorption linearly proportional to the relative humidity. Significant improvement in resistance to water disintegration for crosslinked starch-PVOH films was observed. While the tensile strength decreased with increased relative humidity, crosslinking significantly improved the tensile strength. Increased PVOH content improved elongation of films even when the relative humidity was 80% or higher. Biodegradation studies revealed that the degradation rate was negatively correlated with the PVOH content in films and crosslinking generated more converged degradation curves. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.     

硫酸盐还原菌生理特性及其在废水处理中的应用

硫酸盐还原菌(SRB)是一类利用硫酸盐或者其他氧化态硫化物作为电子受体来异化有机物质的严格厌氧菌.介绍了SRB的生理特性及检测方法,在阐明SRB降解水中污染物原理的基础上,充分探讨了SRB在处理重金属废水、无机和有机废水中的应用现状及研究进展,指出SRB固定化技术是其发展的必经之路.     

影响脱硫塔性能的因素分析与研究

湿法烟气脱硫是成熟且具有较好发展前景的工艺,其中关键是对脱硫塔的选择及通过各项参数的控制达到良好的脱硫效率.通过对脱硫塔酸碱度(PH)、气液比(L/G)、流场特性、结垢等各种性能进行分析研究,对脱硫塔的选择和实际运行具有一定的指导意义.     

高活性萘降解细菌Hydrogenophaga Palleronii LHJ38的研究

为了研究微生物对多环芳烃的降解和转化规律,以萘作为研究对象,从餐厨油烟污染土壤中筛选到一株萘降解活性较高的细菌菌株,经菌种鉴定,定名为帕氏氢噬胞菌(H ydrogenophaga Palleronii)LH J38。测定了该菌的生长曲线和萘降解曲线,建立了菌株对萘的降解活性的定量测定方法,并研究了其最适生长条件。结果表明,在28℃、初始pH6.6、碳氮摩尔比为4的最适培养条件下,LH J38对初始质量浓度为2 000m g/L的萘在96h内的降解率可达98%以上;处于对数生长期的LH J38对萘的降解活性可达47.3nm o l/(m g.m in)。     

乌鲁木齐市东南部荒山植被类型及其特征

采用典型样地法对乌鲁木齐市东部荒山植被进行了调查.依据中国植被和新疆植被分类的原则,遵循群落学-生态学原则,用重要值优势度分类方法确定各层片优势种.将此地区自然植被划分为5个植被型,8个植被亚型、20个群系和24个群丛.并对植被型的基本特征进行了分析和描述.     

渭河径流特性研究

由于工农业的快速发展,渭河径流逐年减少,污染加重,河道淤积不断发展,洪涝灾害时有发生,对中下游人民生产生活造成严重影响.为了减少洪害,减轻污染,必须保证渭河常年径流稳定.