超声波处理剩余活性污泥促进厌氧消化

用超声波处理剩余活性污泥(简称污泥),考察了污泥絮体结构、污泥中溶解性化学需氧量(SCOD)的变化规律及超声波处理对污泥厌氧消化的影响。实验结果表明,声强大于1 040W/m2时,用超声波处理污泥30m in以上,污泥絮体被打碎,污泥絮体结构遭到严重破坏,污泥中SCOD迅速增加,加速了污泥中有机质的水解反应;声强为2 000W/m2时,用超声波处理污泥60m in,中温((37±1)℃)厌氧消化10d,COD去除率为41%;厌氧消化25d的总产气量比未经超声波处理的污泥总产气量提高了53%;将发酵罐容积放大10倍,经超声波处理的污泥25d累积的总产气量比未经超声波处理的污泥总产气量提高了约25%。     

Life Cycle Assessment of Polysaccharide Materials: A Review

Apart from conventional uses of polysaccharide materials, such as food, clothing, paper packaging and construction, new polysaccharide products and materials have been developed. This paper reviews life cycle assessment (LCA) studies in order to gain insight of the environmental profiles of polysaccharide products (e.g. viscose or natural fibre polymer composites) in comparison with their conventional counterparts (e.g. cotton or petrochemical polymers). The application areas covered are textiles, engineering materials and packing. It is found that for each stage of the life cycle (production, use phase and waste management) polysaccharide-based end products show better environmental profiles than their conventional counterparts in terms of non-renewable energy use (NREU) and greenhouse gas (GHG) emissions. Cotton is an exception, with high environmental impacts that are related to the use of fertilisers, herbicides, pesticides and high water consumption. The available literature for man-made cellulose fibres shows that they allow to reduce NREU and GHG emissions in the fibre production phase. No study has been found for the fabric production and the use phase of man-made cellulose textiles.

光伏发电有功自动控制技术

进行了两根足尺预应力型钢混凝土简支梁在火灾高温和竖向恒定加载耦合作用下的耐火性能试验,分析了试验梁的温度场分布规律、竖向变形特点和承载性能劣化过程。通过在试验梁端部预设压力传感器,实测了升温过程中梁端部预压力与升温时间的关系曲线。试验结果表明,预压力对火灾高温作用较为敏感,当标准升温100 min时预压力已降至初始预压力的一半,试验中一根梁出现了侧向弯曲变形。因此,对于预应力混凝土结构,火灾高温作用下应考虑构件可能的侧向变形影响。     

地震烈度与震时避险

地震是突发性极强的自然现象,地震灾害具有成灾迅速、破坏性强、影响面大等特点,如何在震时做出科学正确的应急避险选择,既取决于平时的应急避险准备,更取决于震时果断正确的应急避险方式.地球上每年平均发生500多万次地震,是不是所有的地震都需要应急避险呢?显然不是.需要应急避险的是那些可能对人们造成伤害的地震.为此,需要了解地...     

沉积物再悬浮-重金属释放机制研究进展

水-沉积物界面重金属迁移和转化行为已成为水环境质量研究的热点。因自然、生物、人为活动等驱动的沉积物再悬浮使得沉积物颗粒吸附和结合的重金属可能通过吸附-解吸平衡和氧化还原反应而释放进入上覆水体。随着外在污染源输入逐步得到控制,沉积物再悬浮释放重金属将成为水体重要的内在污染源而对水环境质量和水生生物产生影响。本文综述了最近几年的相关研究文献,对沉积物再悬浮的动力来源及发生机制、再悬浮-重金属释放机制及主要影响因素进行了阐述,探讨了该领域未来可能的研究方向。相关研究发现,当干扰切应力大于沉积物的临界切应力值时,沉积物再悬浮发生,且再悬浮颗粒量随干扰切应力的增强而增大;再悬浮使还原态沉积物暴露于有氧环境,有机质和硫化物的氧化是沉积物结合态重金属释放的主要机理,而沉积物颗粒电性吸附的重金属则通过解吸进入水体;切应力大小、再悬浮水体理化性质、沉积物理化性质以及微生物活性等因素调控着沉积物吸附态或结合态重金属的释放。本文指出再悬浮沉积物释放重金属的去向（再分配机理）以及再悬浮-重金属释放的动力学过程、沉积物悬浮-重金属释放复合预测模型的建立、沉积物悬浮-释放重金属的生物可利用性及生物毒害评价将是本领域需要进一步研究的重点。     

小流域管理与规划信息系统研制

以江苏省溧阳市同官片流域为例,通过建立小流域管理与规划信息系统,探求流域治理新模式,以促进流域经济的良性发展。简要介绍了基于小流域的系统设计和建立方法,系统的功能及其应用实例。     

高效液相色谱法分析水中痕量多环芳烃

本文利用高效液相色谱法测定水中痕量多环芳烃（ＰＡＨｓ）。以二氯甲烷作溶剂,超声提取水中痕量ＰＡＨｓ;甲醇、水作流动相,梯度淋洗,用程序可变波长荧光检测器测定。ＰＨＡｓ浓度为０．００７＝０．６μｇ·ｍｌ＾－１范围时,线性相关系数均在０．９９９９以上;峰高、峰面积的相对标准偏差（ｎ＝１０）分别为１．０１－１．８５％,２．００－３．９４％;检测限（Ｓ／Ｎ＝２）为３．１－２３．０ｐｇ;实际水样的加标回收率     

丛枝菌根真菌接种对兔眼蓝莓在华南地区生长的影响

在盆栽条件下,利用根际接种丛枝菌根真菌（地表球囊霉Glomus versiforme和摩西球囊霉Glomus mosseae）的方法对兔眼蓝莓（Vaccinium ashei）在华南地区生长的影响进行了研究。结果表明：与未接种对照相比,接种的2个真菌均可不同程度地侵染兔眼蓝莓根系,增加根系总长、根表面积、植株地上部分鲜质量、新枝长度、主枝数和主枝长度等,促进兔眼蓝莓生长。地表球囊霉接种侵染率高,对兔眼蓝莓生长促进效果更好。接种AMF还能提高根际土壤w（P2O5）。接种丛枝菌根真菌有利于在华南地区引种栽培兔眼蓝莓。     

Removal of Zn2+ from aqueous solution by biomass of Agaricus bisporus

Biosorption of Zn²⁺ from aqueous solutions by biomass of Agaricus bisporus was investigated. The removal rates of Zn²⁺ by A. bisporus under different parameters (e.g., solution pH, bio-sorbent dosage and initial Zn²⁺ concentration) were studied. The inhibition of A. bisporus’s biosorption by anionic ligands EDTA (Ethylene Diamine Tetraacetic Acid), acetate and citrate) implied that EDTA and citrate might be used as eluting reagents. Regular and simultaneous solution pH change and light metal ions release after biosorption indicated that an ion exchange mechanism was involved. From FT-IR (Fourier Transform Infrared) spectroscopy, the main functional groups participated in biosorption were found. Biosorption of Zn²⁺ by A. bisporus could be well described by the Freundlich and Langmuir models. In conclusion, the biomass of A. bisporus showed high potential for the treatment of wastewater containing Zn²⁺.     

模拟降雨条件下农田径流中氮的流失过程

在室内降雨模拟试验条件下,研究暴雨径流中农田氮素养分流失及施肥处理的影响。结果表明,农田暴雨径流氮养分的流失量与累积径流量成正相关;施用NH