农药污染地下水的微生物治理及含水层渗透性变化研究

采用了从农药厂阿特拉津生产车间排污口污泥中分离出的力种AT菌，进行了农药阿特拉津污染地下水微生物治理的模拟实验研究，在实验条件（T＝10℃，pH=7.5）与野外含水层的条件基本一致情况下，难于生物降解的污染质阿特拉津的一次投菌降解率可达31.08%；设计了两种有效细菌的投放方式以模拟野外条件下的菌种投加条件。另外，AT菌的作用会造成被治理含水层的渗透性能降低，两种投菌方式下，实验后含水层的渗透系数分别下降60.54％和34.56%。清水冲洗10d的渗透性恢复率分别为48.96%及81.36％，说明清水渗透恢复的方法效果明显。     

静态环境下阿特拉津的生物降解研究

从农药厂阿特拉津生产车间污泥中分离出菌种AT菌,进行了系列降解实验.不同温度的降解实验表明,在4～20℃的实验温度范围内,AT菌能够降解代谢污染质,并随温度的升高,降解能力增强.20℃时降解率为38.84%;AT菌在外加氮源、碳源及以阿特拉津为惟一碳源和氮源等条件时对农药污染质阿特拉津均具有降解能力,且在以阿特拉津为惟一氮源(外加碳源)条件下的降解效果最好,此时的降解率为30.39%.     

静态环境下阿特拉津的生物降解研究

从农药厂阿特拉津生产车间污泥中分离出菌种AT菌，进行了系列降解实验。不同温度的降解实验表明，在4～20℃的实验温度范围内，AT菌能够降解代谢污染质，并随温度的升高，降解能力增强。20℃时降解率为38．84％；AT菌在外加氮源、碳源及以阿特拉津为惟一碳源和氮源等条件时对农药污染质阿特拉津均具有降解能力，且在以阿特拉津为惟一氮源（外加碳源）条件下的降解效果最好，此时的降解率为30．39％。     

一种新嗜冷菌JLNY02降解地下水中阿特拉津的研究

从某农药厂排污口采集污泥样品，通过富集培养，从中分离筛选出一株阿特拉津高效降解菌JLNY02，并进一步对其降解的影响因素进行研究。在10℃的条件下降解阿特拉津，其降解率可达81.8%，而在高温下的降解率较低，仅31．4％。     

腐殖酸和铁对阿特拉津光降解影响的研究

为考察除草剂在水体中的自净性能，对模拟太阳光(λ> 290 nm)下腐殖酸和铁元素对阿特拉津的光化学降解进行了研究。结果表明，单独辐照阿特拉津几乎不降解。在分别加入3、5和10 mg/L的腐殖酸时，阿特拉津的降解率分别为34.36 %、40.74%和15.66 %；在Fe(Ⅲ)投加量从0.01 mmol/L增加到0.2 mmol/L时，阿特拉津的降解率从24.36 %增加到34.97 %。而在当腐殖酸与铁共存时，阿特拉津降解率则进一步提高。紫外可见光谱和荧光光谱均表明，腐殖酸-铁络合物的形成及其光化学作用，促进了阿特拉津的降解。     

水中腐殖酸可见光降解阿特拉津的动力学研究

探讨了天然水体中存在的腐殖酸(HA)可见光降解水中阿特拉津的动力学特征和影响因素。结果表明,pH对HA可见光降解阿特拉津具有明显影响,水中HA质量浓度为5.0mg/L时,pH为3、5、7、9的条件下,受可见光照6.00h后阿特拉津(初始质量浓度5mg/L)的去除率分别为75.5%、77.3%、91.7%、84.9%,中性条件下阿特拉津可见光降解效果最佳;当HA质量浓度分别为1.5、3.0、5.0、10.0mg/L时,HA对水中阿特拉津的可见光降解均表现为促进作用,且降解过程符合一级反应动力学方程,其一级反应动力学常数分别为0.337 0、0.361 4、0.445 4、0.314 6h-1,HA为5.0mg/L时阿特拉津的可见光降解效果最佳。实际应用中,可以通过优化HA与阿特拉津的浓度比值,发挥HA促进阿特拉津可见光降解的最佳效能。     

寒地黑土中阿特拉津降解菌的筛选及降解特性

从长期施用阿特拉津的寒地黑土耕层(0～10 cm)取样。利用富集培养的方法，筛选到2株阿特拉津降解菌，编号Z₉和Z₄₂。Z₉以阿特拉津为惟一碳氮源生长，Z₄₂以阿特拉津为惟一氮源生长，15 d对阿特拉津的降解率分别为77.7%和65.6%。对其初步鉴定并对降解特性进行研究，结果表明，细菌Z9为微杆菌属（Microbacterium sp.），细菌Z₄₂为节杆菌属(Arthrobacter sp.)。在室内进行降解条件优化实验，得出2株降解菌对100 mg/L阿特拉津的最佳降解条件为：温度30℃,Z₉ pH值为7，Z₄₂ pH值为8。     

饮用水原水中微量阿特拉津去除方法试验研究

饮用水中微量有机物的污染是关系饮用水生态安全的重要问题。以饮用水中微量的内分泌干扰类除草剂阿特拉津为研究对象，分别采用微生物降解技术和光催化氧化技术对其进行降解，考察温度对阿特拉津降解效果的影响。研究结果表明：阿特拉津浓度为1 mg/L时，3种温度条件下，除锰功能菌MB4对阿特拉津均有明显的去除效果，降解时间为7 d时，阿特拉津的去除率达到65%。底物浓度为200 μg/L，3种温度条件下，活性炭负载二氧化钛（TiO₂/PAC）催化剂光降解阿特拉津30 min时，其去除率均达到90%。光催化氧化技术协同微生物降解技术在饮用水中微量的内分泌干扰物的去除中有广阔的应用前景。     

O3/H2O2降解阿特拉津影响因素研究

采用O3/H2O2氧化去除水中内分泌干扰物阿特拉津,考察了反应条件及水质对去除的影响,并对反应机制进行了初步探讨.阿特拉津初始浓度2 mg/L,投量为7.5 mg/L的O3单独氧化去除率为27.2%;相同O3投量下,控制H2O2/O3摩尔比为0.75,5 min阿特拉津的去除率最高可达96.5%;pH值为7.5～8.5,温度在25～40℃的范围内,都维持了较高的去除率,表明H2O2/O3体系对阿特拉津的去除效果良好,降解速度快,反应条件温和.0.5 mg/L的腐殖酸,对阿特拉津的去除影响不大,腐殖酸浓度为1、2和5 mg/L时,平均去除率分别为63.4%、50.7%和30.2%;碳酸氢钠的浓度为50和200 mg/L时,去除率分别为88.1%和73.8%,说明水质对阿特拉津的去除影响较大.叔丁醇的浓度为5和20 mg/L时,阿特拉津的去除率分别降低到44.7%和27.5%,去除率随自由基抑制剂叔丁醇增加而降低,说明H2O2/O3降解阿特拉津主要为该体系产生的羟基自由基的贡献.     

羟基氧化铁催化臭氧氧化去除水中阿特拉津

以实验室制备的羟基氧化铁(FeOOH)为催化剂,研究了其催化臭氧氧化去除水中痕量阿特拉津的效能,并对影响催化效果因素及降解机理进行了探讨。在本实验条件下,反应8 min时催化氧化阿特拉津的去除率比单独臭氧氧化高出63.2%,而FeOOH对阿特拉津的吸附量很小,结果表明,FeOOH对臭氧氧化水中的痕量阿特拉津具有明显的催化活性。探讨了催化剂投量、pH、阿特拉津初始浓度和重碳酸盐碱度对催化氧化阿特拉津的影响。催化剂最佳投量为150 mg/L,去除率随pH和阿特拉津初始浓度的增加而升高,重碳酸盐浓度为200 mg/L时催化作用受到明显抑制。通过研究叔丁醇对催化反应的影响间接推断了催化反应的机理,叔丁醇作为羟基自由基抑制剂有效地抑制了水中羟基自由基的生成和它对阿特拉津的氧化反应,间接证明这种催化作用遵循羟基自由基的反应机理。     

次氯酸钠发生器的研制

介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠     

An application of the theory of kinematics of mixing to the study of tropospheric dispersion

The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.     

Estimation of uncertainty of sampling for analysis of pesticide residues

Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.     

Evaluation of the presence of drugs of abuse in tap waters

A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L⁻¹, in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L⁻¹. Illicit drugs were sparsely present and usually at ultratrace level (<1 ng L⁻¹). For example, cocaine has mean values of 0.4 (Spain) and 0.3 ng L⁻¹ (worldwide), whereas for benzoylecgonine, these mean values were 0.4 and 1.8 ng L⁻¹, respectively. Higher concentrations of benzoylecgonine were found in Latin American samples (up to 15 ng L⁻¹). No opiates were identified in any sample but the presence of methadone and EDDP was frequently detected. Total mean values for EDDP were 0.4 ng L⁻¹ (Spain) and 0.3 ng L⁻¹ (worldwide). Very few samples tested positive for amphetamines, in line with the reactivity of chlorine with these compounds. No cannabinoids, LSD, ketamine, fentanyl and PCP were detected.     

不同泥源对厌氧氨氧化反应器启动的影响

采用2套上流式生物膜反应器,分别接种少量厌氧氨氧化污泥和大量硝化污泥,考察其对厌氧氨氧化反应器启动的影响。污泥接种入反应器后,测得接种厌氧氨氧化污泥的反应器(R1)内MLSS为0.22 g/L,另一个反应器(R2)MLSS为2.7 g/L。与直接接种厌氧氨氧化污泥相比,R1经过72 d的运行才显现出厌氧氨氧化特性。经过114 d的培养,前者氮去除速率由0.23 kg/(m3.d)提升到5.29 kg/(m3.d),总氮去除率大于89%;R2的氮去除速率由0.01 kg/(m3.d)提升到1.1 kg/(m3.d),总氮去除率大于84.6%。说明普通污泥启动需要一个较长的筛选过程,直接接种少量的厌氧氨氧化污泥比接种普通的污泥能够更快启动厌氧氨氧化反应器。     

Mechanisms of biodegradation of dibenzoate plasticizers

Biodegradation mechanisms were elucidated for three dibenzoate plasticizers: diethylene glycol dibenzoate (D(EG)DB), dipropylene glycol dibenzoate (D(PG)DB), both of which are commercially available, and 1,6-hexanediol dibenzoate, a potential green plasticizer. Degradation studies were done using Rhodococcus rhodochrous in the presence of pure alkanes as a co-substrate. As expected, the first degradation step for all of these systems was the hydrolysis of one ester bond with the release of benzoic acid and a monoester. Subsequent biodegradation of the monobenzoates of diethylene glycol (D(EG)MB) and dipropylene glycol (D(PG)MB) was very slow, leading to significant accumulation of these monoesters. In contrast, 1,6-hexanediol monobenzoate was quickly degraded and characterization of the metabolites indicated that the biodegradation proceeded by way of the oxidation of the alcohol group to generate 6-(benzoyloxy) hexanoic acid followed by β-oxidation steps. This pathway was blocked for D(EG)MB and D(PG)MB by the presence of an ether function.The use of a pure hydrocarbon as a co-substrate resulted in the formation of another class of metabolites; namely the esters of the alcohols formed by the oxidation of the alkanes and the benzoic acid released by hydrolysis of the original diesters. These metabolites were biodegraded without the accumulation of any intermediates.     

混凝试验搅拌器的研制

影响混凝效果的因素众多,混凝沉淀烧杯试验是进行水的混合、絮凝、沉淀工艺研究、设计和生产指导的最有效方法之一,阐述了智能型混凝试验搅拌器的设计原理和技术性能.     

生物质快速热裂解主要参数对生物油产率的影响

以松木木屑为原料,在自制的小型流化床上,开展了生物质热裂解温度、生物质粒径和进料速率对生物油产率的影响实验研究.结果表明,在热裂解温度分别为450、475、500、525和550℃条件下,当热裂解温度为500℃时,生物油产率最高,平均产率达到53.33%(质量百分比).反应温度越高,炭产量越低,不可冷凝气体产量越高,气体发热值越高;粒径＜1 mm的生物质其粒径对生物油产率影响不大;生物质进料速率增加时,生物油产率增加.本研究为生物能的利用提供了新的途径.     

Visualisation of the complexity of EUSES

The interdependencies of parameters applied in the models of EUSES are visualised in a directed connectivity graph. The parameters (inputs, defaults, state variables, outputs) are represented by boxes (nodes) and their relations by lines (edges). The visualisation, on the one hand, clarifies the complexity of the models in EUSES and, on the other hand, creates an overview and transparency. The parameters’ relations to each other can be recognised faster, and the models can be better understood. The complexity was quantified by the number (variety), kind (substance parameter, physico-chemical parameter, concentration, other parameters), and depth (dimension) of the parameter and the number of relations (connectivity). The variety of EUSES (without the modelsSimple Treat andSimple Box whose interior structure is not documented and without the effect and risk characterisation) amounts to 466, the connectivity to 961, and the maximal dimension is 21.     

产油微藻培养与回收的关键技术研究进展

寻找廉价而高效的替代原料是实现生物柴油产业化的关键所在.微藻以含油量高、生长周期短、环境适应能力强、生物产量高等优点,有望成为一种极具潜力的生物柴油生产原料.然而,目前尚存在微藻培养低效成本高和微藻回收效率低两大难题.综述了微藻培养与回收过程中的关键技术,并对存在的两大难题及其改进技术进行了详细的探讨.最后,总结并展望了微藻培养、回收技术未来的发展趋势.