基层环境保护工作应规避的误区——以伊犁州(直)县市为例

伊犁州的环境保护工作在认识、作为和责权上存在一些误区,导致人为加大了环境保护工作的难度。如何规避这些误区首先必须依法行政,其次须紧密结合当地良好的生态环境,坚持污染防治与生态保护并重的工作格局,这既是服务于伊犁州(直)经济发展大局的需要,也是保护生态安全屏障的具体要求。     

威远县地质灾害发育规律及成因分析

威远县地质灾害活动频繁,崩塌和滑坡等地质灾害分布广泛。通过对威远县地质灾害分布特征的研究发现,研究区地质灾害点多,但其分布具有一定的区域性,主要分布在低山区。针对这一特性,以威远构造特征为背景,结合区域地质灾害调查资料,分析地质灾害发育的影响,得出背斜构造不仅为地质灾害的发生提供构造条件,而且控制着研究区内的地貌格局,地层岩性是决定地质灾害发育的物质基础。通过本次研究将进一步了解该区地质灾害发育规律及形成原因,对该区地质灾害防治工作提供理论指导。     

影响银淡水生物水质基准的环境因素分析

水质基准是制定水环境质量标准,以及评价、预测和控制与治理水体污染的重要依据。为了系统分析水体硬度、物种门类和地域条件对水质基准的影响,本研究筛选了6门20科25种水生生物的毒性数据,用毒性百分数排序法推导了中国银的淡水生物水质基准。研究结果表明,银的基准最大浓度(CMC)与水体硬度呈幂函数关系,等式为CMC=0.85×e[0.62ln(水体硬度)-4.28]μg·L-1,基准连续浓度为0.02μg·L-1。中国和美国2个不同生物区系研究都表明低等生物(无脊椎动物)比高等生物(脊椎动物)对银离子的毒性更为敏感。由地域条件引起的生物区系和敏感物种差异及基准推导方法的不同也会影响水质基准值。     

Evaluation of carbon-based nanosorbents synthesised by ethylene decomposition on stainless steel substrates as potential sequestrating materials for nickel ions in aqueous solution

The present work covers the preparation of carbon-based nanosorbents by ethylene decomposition on stainless steel mesh without the use of external catalyst for the treatment of water containing nickel ions (Ni²⁺). The reaction temperature was varied from 650 to 850℃, while reaction time and ethylene to nitrogen flow ratio were maintained at 30 min and 1:1 cm³/min, respectively. Results show that nanosorbents synthesised at a reaction temperature of 650℃ had the smallest average diameter (75 nm), largest BET surface area (68.95 m²/g) and least amount of impurity (0.98 wt.% Fe). A series of batch sorption tests were performed to evaluate the effects of initial pH, initial metal concentration and contact time on Ni²⁺ removal by the nanosorbents. The equilibrium data fitted well to Freundlich isotherm. The kinetic data were best correlated to a pseudo second-order model indicating that the process was of chemisorption type. Further analysis by the Boyd kinetic model revealed that boundary layer diffusion was the controlling step. This primary study suggests that the prepared material with Freundlich constants compared well with those in the literature, is a promising sorbent for the sequestration of Ni²⁺ in aqueous solutions.     

声学环境影响评价——大剧院设计声学案例分析

大剧院观众厅是音乐家最后的乐器,音乐效果是由观众厅声学反应出来的。前面演奏者要把声音传播给观众席,再从观众席后排反声回给演奏者,这样的互动是最完美的剧院设计。     

黄泔水发酵微生物絮凝剂B-12的研究

以黄泔水为廉价培养基,对絮凝剂产生菌B-12进行发酵培养,用单因素实验和正交设计试验,考察了培养基条件对絮凝剂产生菌絮凝效果的影响。结果表明:B-12的优化培养条件为:黄泔水体积分数为12.5%,硫酸铵为0.5g/L,温度为28℃,初始培养pH为6.5。在此条件下所产生的絮凝剂对高岭土悬液絮凝率高达81.2%。利用黄泔水生产的微生物絮凝剂B-12对化粪池废水、城市生活污水和土壤悬浊液具有良好的絮凝效果。     

Toxicity-based assessment of the treatment performance of wastewater treatment and reclamation processes

The reclamation and reuse of wastewater is one of the possible ways to relieve the serious fresh water resource crisis in China. Efficient reclamation treatment technologies ensure the safe reuse of reclaimed water. In order to screen out and evaluate technologies appropriate for reclamation treatment, a great deal of efforts have been brought to bear. In the present study, a toxicity-based method including a Photobacterium phosphoreum test for acute toxicity and SOS/umu test for genotoxicity, accompanied by the traditional physicochemical parameters DOC (dissolved organic carbon) and UV₂₅₄ (absorbance at 254 nm), was used to measure the treatment performance of different reclamation processes, including the anaerobic-anoxic-oxic biological process (A²O) and subsequent physical/chemical reclamation processes (ultrafiltration, ozonation, chlorination). It was found that for the secondary effluent after the A²O process, both the toxicity and physicochemical indices had greatly decreased compared with those of the influent. However, chemical reclamation processes such as ozonation and chlorination could possibly raise toxicity levels again. Fortunately, the toxicity elevation could be avoided by optimizing the ozone dosage and using activated carbon after ozonation. It was noted that by increasing the ozone dosage to 10 mg/L and employing activated carbon with more than 10 min hydraulic retention time, toxicity elevation was controlled. Furthermore, it was shown that pre-ozonation before activated carbon and chlorination played an important role in removing organic compounds and reducing the toxicity formation potential. The toxicity test could serve as a valuable tool to evaluate the performance of reclamation processes.     

Measurement of semivolatile carbonaceous aerosols and its implications: A review

Measurement of carbonaceous aerosols is complicated by positive and negative artifacts. An organic denuder with high efficiency for removing gaseous organics is an effective approach to eliminate the positive artifact, and it is a precondition for the accurate determination of SVOC by an adsorbent backup filter. Evaluations of different configurations of the organic denuder, and SVOC determined by different denuder-based samplers, both integrated and semi-continuous, are reviewed. A new equation for determination of the denuder efficiency is estimated, considering the efficiency of removing both the gaseous organics that could be adsorbed by the quartz and the gaseous passing through the quartz that could be subsequently adsorbed by the backup adsorbent filter. The origin of OC on the backup quartz filter, behind either quartz or Teflon filter, is quantitatively evaluated by the denuder-based method based on the data published. The backup-OC is shown to be dominated by either gaseous organics passing through the front filter or the evaporated particulate organic carbon depending on the sampling environment.     

土壤中锗的形态提取和形态分布研究

本文对不同类型土壤中锗的存在形态、开态分布和有效锗进行了研究,选择了合适的提取剂,建立了土壤中锗的形态连续提取方法。探讨了影响土壤中锗形态分布的因素。锗在土壤中主要以残渣态、酸可提态和有机结合态形式存在,土壤有机质能富集锗,此外,还试验了土壤有效锗与盆栽玉米吸收锗的相关性。