一种特殊电除尘器钢支架计算方法的讨论

以某工程为例,介绍了一种特殊电除尘器钢支架的结构形式,通过结构设计软件计算和有限元整体屈曲分析,证明采用传统的计算长度系数法进行立柱稳定计算,其结果偏不安全,建议采用整体屈曲分析计算.     

Evaluation of the fish short term reproduction assay for detecting endocrine disrupters

In a fish testing strategy, positive results of the fish short term reproduction assay (FSTR), often trigger a definitive test like the fish sexual development test (FSDT) or the fish full life cycle test (FFLC), entailing ethical and economic problems. This study analysed 137 studies encompassing 35 chemicals with different modes of actions (MOAs). Variability is quantified for MOA endpoints vitellogenin (VTG) and secondary sex characteristics (SSCs) as well as for apical endpoints. Two MOA endpoints could indicate estrogenic, anti-estrogenic, androgenic, anti-androgenic and steroidogenesis activities. Great variability, however, has been observed for chemicals with anti-androgenic and steroidogenesis activities, suggesting that TG229/230 may not be sensitive enough to detect these types of chemicals and may produce false negatives. Changes in apical endpoints like fecundity are not limited to endocrine disrupting chemicals (EDCs). Non-EDCs could induce the similar effects on these apical endpoints. If elucidating MOA is needed, targeted in vitro MOA tests are suggested. Positive in vitro MOA results trigger a definitive test, which could be used for confirmation of the MOA in vivo and for deriving a no observed effect concentration (NOEC). Based on positive MOA results of TG229, a definitive test such as the FSDT or the FFLC is still needed, because the current TG229 has limitation on the derivation of a NOEC. An extended TG229 with more power to detect reproduction effects, as recently proposed in the OECD test guideline program, would improve the possibility to derive a NOEC and increase its usefulness in risk assessment.     

Fe/活性炭多相类Fenton法湿式氧化罗丹明B废水的研究

采用自制的Fe/活性炭（Fe/AC）为催化剂，H₂O₂为氧化剂,组成多相类Fenton试剂催化降解罗丹明B染料废水。实验结果表明,在催化剂加入量为0.8 g/L，H₂O₂体积分数为0.3%,废水pH值为13,反应时间为30 min的条件下,质量浓度为200 mg/L的罗丹明B染料废水的脱色率达100%。反应动力学研究表明,罗丹明B脱色反应近似为一级反应,30℃时反应速率常数为0.02675 min^-1,表观活化能为69.47 kJ/mol。     

炉渣制光催化剂催化降解水中罗丹明B的研究

以废弃的钢铁冶炼炉渣为原料制备了光催化剂GN,并对其进行了X衍射、紫外-可见漫反射吸收光谱、比表面积及孔径分布等物性测试,通过在三相内循环流化床光催化反应器中对罗丹明B废水进行处理,确定了GN的最佳光催化氧化条件.将GN与传统的光催化剂TiO2作比较,结果表明,GN不仅具备较高的光催化活性,而且成本更低,为钢铁冶炼炉渣的循环再利用提供了一种新思路,同时也为光催化氧化技术的工业化应用提供了一条新颖、经济、可行的途径.     

Characteristics and significance of liquid effluent from woodchip corrals in Scotland

Woodchip corrals are increasingly used as cost effective means of over-wintering livestock in temperate regions but there is little information on their potential environmental impact. Four woodchip corrals of varying characteristics were instrumented to capture and quantify the flows reaching the base, where pollutant fluxes may move either vertically to groundwater, or laterally to a water course. Samples for chemical analysis were collected daily by auto-sampler. Samples for bacterial analysis were aseptically hand-sampled. Sampling frequency was increased during high flow events and sampling was conducted over a 12-month period. Microbiological samples were analysed for total coliform (TC), presumptive Escherichia coli (EC) and intestinal enterococci (IE). Leachate was also analysed for total phosphorus, phosphate, total nitrogen, ammonium, total oxidised nitrogen, nitrite and nitrate. Each corral had a recording rain gauge sited within 10 m of the corral surface. Mean total nitrogen concentration in leachate was 339.5 mg l(-1), of which ammoniacal-N comprised approximately 57%. Mean total phosphorus concentration was 94.7 mg l(-1). Geometric mean concentrations of TC, EC and IE were 95,461, 94,983 and 55,552 cfu100 ml(-1), respectively. Significant flows of leachate occurred at the base of the corrals on most days during the 1-year sampling period and flow rate increased with stocking density. Strong positive linear relationships were found between the concentrations of the nutrient parameters and discharge. Strong positive curvilinear relations were found between faecal indicator concentrations and discharge. Different relationships were observed in the stocked and unstocked corrals. The resulting fluxes are sufficient to give concern and to indicate that corral development is worthy of regulatory attention.     

水溶液中活性艳红KE-3B的臭氧超声联合脱除

采用臭氧/超声联合技术去除模拟废水中的活性艳红KE-3B。臭氧/超声处理前后KE-3B的紫外可见吸收谱没有明显的变化。臭氧/超声联合作用、单独臭氧化和单独超声处理脱除活性艳红KE-3B模拟废水5 min后的去除率分别为97%、73%和5%，表明臭氧/超声联合降解活性染料具有更高的氧化速率。实验研究了pH值、臭氧投加量、超声能量密度、反应温度对超声/臭氧降解活性艳红KE-3B反应速率的影响，在实验研究范围内，随着溶液初始pH的增大，KE-3B的去除率先增大后减小，超声能量密度的改变对KE-3B的去除影响不大，温度升高有利于氧化反应的进行。在溶液初始pH值为9.0，臭氧投加量3.2 g/h，超声能量密度176 W/L，反应温度20℃时，浓度为100 mg/L的活性艳红KE-3B溶液的去除率最高。     

Attractancy evaluation of ceralure‐B1 isomer via field captures of mediterranean fruit flies (Diptera: Tephritidae)

Abstract

Commercially prepared ceralure‐B1, an attractant for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), was evaluated in trapping tests by comparison with commercial ceralure and trimedlure. Jackson traps were used for medfly captures. The residual ceralure‐B1, ceralure, and trimedlure contents of aged dispensers were determined. The results of this study show that male medfly captures from traps with ceralure‐B1 were as high or higher than male medfly captures from traps with twice the quantity of ceralure or trimedlure. The use of regioselectively synthesized ceralure‐B1, enriched in B1, as a source of a more potent attractant than commercial ceralure and as a more persistent male medfly attractant than trimedlure is reported.     

Uptake of 17β-estradiol and biomarker responses in brown trout (Salmo trutta) exposed to pulses

In streams, chemicals such as 17β-estradiol (E2) are likely to occur in pulses. We investigated uptake and biomarker responses in juvenile brown trout (Salmo trutta) of 3- or 6-h pulses of concentrations up to 370 ng E2 L⁻¹. Uptake by the fish was estimated from disappearance of E2 from tank water. A single 6-h pulse of 370 ng E2 L⁻¹ increased the plasma vitellogenin concentration, liver Erα- and vitellogenin-mRNA. Exposure to 150-160 ng E2 L⁻¹ for 6 h increased vitellogenin in one experiment but not in another. Two 6-h pulses had a larger effect one pulse. Brown trout in the size range 24-74 g took up E2 linearly with time and exposure concentration with a concentration ratio rate of 20.2 h⁻¹. In conclusion, the threshold for induction of estrogenic effects in juvenile brown trout at short term pulse exposure appears to be in the range 150-200 ng E2 L⁻¹.     

升—降温全过程中约束钢梁的有限元与试验分析

以轴向支撑连接方式,利用自制的加热炉对约束钢梁进行了升—降温全过程的试验研究。重点研究了钢梁的跨中挠度随温度变化的规律,以及梁端不同轴向支撑刚度和钢柱不同轴压比条件下约束钢梁的屈曲模式及其梁端轴向支撑的破坏形态。基于ANSYS有限元软件,采用温度场和结构耦合中的间接法,对升-降温全过程中的约束钢梁进行了有限元分析。数值计算结果与试验结果吻合较好,验证了有限元模型和参数设置的合理性。根据对比分析,讨论了我国现行钢结构防火技术规范中存在的关键问题,特别提出了钢结构抗火设计应有的内涵,为钢结构抗火研究提供了新的思路。     

国内废钢行业概况及废钢价格关联因素的量化研究

介绍了"十五"和"十一五"时期国内废钢行业发展概况,重点阐述废钢行业的回收供应以及消耗情况,并对影响废钢价格的因素进行数学建模,对关联程度大小进行量化,对更好地分析废钢市场走势有较好的指导意义。