横向风作用下喷口间距对射流扩散火焰特征的影响研究*

为研究横向风作用下喷口间距对射流扩散火焰特征的影响,以双喷口火焰为研究对象,利用CCD摄像机拍摄火焰几何形态,研究横向风条件下喷口间距对火焰形态演化、火焰长度和火焰吹熄极限的影响。研究结果表明:喷口间距较小时,2束火焰因空气夹带竞争和压差作用,彼此相互倾斜融合,火焰融合概率随喷口间距增加而逐渐降低,火焰临界融合间距随横向风的增加先增大后减小;由于火焰的空气夹带和热反馈处于较高水平,2束火焰被少量拉伸,火焰长度先增加后减小;喷口间距较小时,火焰吹熄极限显著增加。     

海上溢油处置技术研究进展

分别从物理、化学、生物等类处置技术及最新技术等方面对海上溢油处置进行归纳总结,以期对企业海上溢油处置进行指导和参考。     

喂养金鱼与环保教育

饲养金鱼在我国有悠久的历史金鱼种类很多千姿百态惹人喜爱有很高的观赏价值。我在担任中师班主任工作期间，利用喂养金鱼对全班同学进行环保教育，取得了比较好的效果。在班级组建之初，组织学生买来鱼缸和金鱼。一开始，同学们的热情很高，兴趣很浓，下课时经常围着鱼缸观赏。这时我并没有指派具体的饲养员，同学们自发且无序的喂些食物，偶尔个别同学会把鱼缸端出去晒晒太阳，结果一个星期后这些金鱼都死掉了，同学们都很伤心也很遗憾。于是我组织了主题班会“金鱼为什么死掉了”。在主题班会上，同学们畅所欲言，各抒己见，最后…     

氨法脱硫技术在硫黄装置节能碳减排中的应用

硫黄回收装置是炼化装置的主要废气排放源,通过对氨法与钠碱法脱硫工艺流程、废水排放量、烟气排放指标、运行能耗、碳减排等方面的运行数据对比分析,结果表明,氨法脱硫工艺具有工艺流程简单、节能、无废水、无CO_2产生等优点,综合能耗下降20%以上,是一种高效、低耗能而且脱硫过程中不增加CO_2排放、无二次污染的先进工艺技术,在硫回收装置尾气脱硫领域具有良好的应用前景。     

The Investigation of the Toughening Mechanism of PHBV/PBAT with a Novel Hyperbranched Ethylenediamine Triazine Polymer Based Modifier: The Formation of the Transition Layer and the Microcrosslinking Structure

A new type of designed hyperbranched ethylenediamine trazine polymer (HBETP) is successfully synthesized and characterized based upon NMR and GPC. The prepared HBETP is used to modify the poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV)/poly(butylene adipate-co-terephthalate) (PBAT) blends. The effect of HBETP on the microstructure, mechanical properties and thermal properties of the blends is studied. The results indicate that upon addition of 1.0 wt% of HBETP, the impact strength of the PHBV/PBAT blends is increased by 47.1%; ?T_g of the blends decreases from 53.2 to 49.9 °C. These results, together with the morphology analysis of the fractured surface of the blends, conclude the formation of the transition layer between PHBV and PBAT. Also, the XRD result shows that the addition of HBETP can limit the growth of the PHBV crystals and causes the decrease of both the crystallinity and the grain crystalline size. The DSC result demonstrates that the addition of HBETP mainly affects the crystallization of the HB-HV binary eutectic region within PHBV. The mechanism of PHBV/PBAT toughening is due to the formation of the strong physical hydrogen bonding and the chemical micro-crosslinking between HBETP and PHBV/PBAT, which is proposed based on XPS characterization.     

类芬顿试剂吸收去除气态元素汞

实验初步研究了类芬顿试剂为吸收剂对气态元素汞的脱除性能,考察了铁盐种类、pH、初始汞浓度、反应温度、卤素离子、甲酸添加量等因素对类芬顿试剂脱除气态元素汞性能的影响.结果表明,在pH 3.5条件下,以氯化铁为催化剂时,气态元素汞的脱除效率为76.4%;添加250μg.mL-1Cl-、150μg.mL-1Br-或5.0μg.mL-1甲酸均可以显著提高类芬顿反应体系对气态元素汞的脱除效果,最高脱除效率可达95%以上.     

老化微塑料对水体中重金属铜和锌的吸附行为研究

微塑料（Microplastics,MPs）在水环境中可以作为重金属载体,对金属离子的迁移和毒性效应产生较大影响.本文开展了紫外光老化后的聚丙烯（Polypropylene,PP）和聚乙烯（Polyethylene,PE）对两种重金属离子Cu²⁺和Zn²⁺在单一和二元复合体系中的吸附行为研究.通过拟一级和拟二级动力学模型研究发现,微塑料对重金属离子的吸附过程更符合拟二级动力学过程,利用Langmuir模型和Freundlich模型对吸附等温线结果进行拟合,结果表明,在单一体系中,相同老化条件下的PP相比PE对金属离子的平衡吸附量更高,且对Cu²⁺的吸附量均大于对Zn²⁺;在二元复合体系中,由于竞争吸附作用,MPs对重金属离子的吸附量小于在单一体系中的吸附量,且MPs对重金属离子的吸附过程更符合Freundlich模型,即吸附主要以多层吸附为主.吸附热力学研究表明,老化PP和PE微塑料对Cu²⁺和Zn²⁺的吸附行为属于自发吸热过程.微塑料PP和PE吸附前后对莱茵衣藻的毒性试验结果表明,微塑料存在均对藻类的生长有抑制作用,但吸附重金属后的微塑料对藻的生长抑制率有所降低.通过藻的酶活性（包括超氧化歧化酶（SOD）,丙二醛（MDA）和过氧化氢酶（CAT））的测定结果表明,微塑料对藻造成一定的氧化损伤,而吸附重金属后的微塑料的毒性作用下降.本论文可以为环境中微塑料存在下复合污染物的竞争吸附行为和联合生态效应研究提供理论依据.     

德国发展循环经济对中国的启迪

德国吸取了片面强调经济增长导致生态坏境破坏的惨痛教训,率先在国际上实行发展循环经济政策,在发展循环经济方面积累了丰富的经验,形成了独具特色的循环经济管理体系。借鉴德国先进经验,认为转变经济发展模式,发展循环经济是中国实现全面可持续发展的战略选择,介绍了德国在理论、实践方面的经验,对正处于经济水平与环境保护有待于进一步协调发展的中国而言,具有现实的参考意义。     

Modeling the Effects of Extreme Drought on Pollutant Transport Processes in the Yangtze River Estuary

Water resources in the Yangtze River Estuary (YRE), which is the vital water supply for Shanghai, decreased by approximately 2.45 Gm³ in 2006, the second‐worst recorded drought year. A numerical model was developed to investigate the effects of this extreme drought on pollutant transport processes in the YRE. The model was calibrated against observations and displayed good agreement. Residence time, a critical hydrodynamic indicator, was implemented to indicate pollutant transport processes. Numerical experiments were conducted to examine the possibly drought‐induced influences. The model results demonstrated that the influences on pollutant transport processes varied spatially and temporally, and these influences could partly explain the observed temporal and spatial variations of total nitrate in 2006. The area most susceptible to drought is in the north branch with 2‐11 days' extension of residence time. As the drought occurred in both the high and normal water periods, its influences were more significant during the normal water period with saltwater intrusion into the north branch. The drought also introduced a pollutant transport lag in timescale of approximately five days by diminishing the seaward advection flux with freshwater discharge. In 2006, the magnified tidal influence during the drought contributed more than usual to structuring pollutant transport, as the pollutant transport processes were intensely associated with tidal flow and tidal cycle.