地震与环境生态

基于地震环境生态破坏的实际资料,我们讨论了以下的问题;（1）从Ⅸ度地震烈度开始就会引起环境生态的破坏;（2）初步划分Ⅸ－Ⅻ度情况下地地震对环境生态破坏程度;（3）得出了在发生6．7级－8．5级地震时环境生态破坏的面积;（4）提出了地震引起环境生态破坏的恢复和补救对策。     

近500年京津冀地区最严重的干旱和社会对干旱的响应

本文确定了京津冀地区近500年米最严重的干旱时段。讨论了社会对干旱的响应。说明了干旱已是制约该区经济发展的重要因素。     

Aging-independent and size-dependent genotoxic response induced by titanium dioxide nanoparticles in mammalian cells

Titanium dioxide nanoparticles(TiO_2 NPs) are subjected to various transformation processes(chemical, physical and biological processes) in the environment, potentially affecting their bioavailability and toxic properties. However, the size variation of TiO_2 NPs during aging process and subsequent effects in mammalian cells are largely unknown. The aim of this study was to illustrate the adverse effects of TiO_2 NPs in different sizes(5, 15 and 100 nm) during aging process on human-hamster hybrid(A_L) cells. There was an aging-time dependent enhancement of average hydrodynamic size in TiO_2 NPs stock suspensions. The cytotoxicity of fresh TiO_2 NPs increased in a size-dependent manner; in contrast, their genotoxicity decreased with the increasing sizes of NPs. No significant toxicity difference was observed in cells exposed to either fresh or 60 day-aged TiO_2 NPs. Both Fresh and aged TiO_2 NPs efficiently induced mitochondrial dysfunction and activated Caspase-3/7 in a size-dependent manner.Using mitochondrial-DNA deficient(ρ~0) ALcells, we further discovered that mitochondrial dysfunction made significant contribution to the size-dependent toxicity induced by TiO_2 NPs during the aging process. Taken together, our data indicated that TiO_2 NPs could significantly induced the cytotoxicity and genotoxicity in an aging time-independent and size-dependent manner, which were triggered by mitochondrial dysfunction. Our study suggested the necessity to include size as an additional parameter for the cautious monitoring of TiO_2 NPs disposal before entering the environment.     

蓟运河水中甲基汞形态分布研究

以受汞污染的蓟运河水为对象,用化学平衡模拟方法研究了甲基汞不同形态的分布规律,运用IECWDI计算水体系化学平衡程序,收集蓟运河水九种金属离子、十种配体数据,考虑了72种络合物物种,25种可能生成的固体和两个氧化还原体系,计算中需用的甲基汞与黄腐酸络合物常数,建立了溶剂萃取法进行测定。最后计算了盐度、pH、pE等对形态分布的影响。     

An overview of emissions of SO2 and NOx and the long-range transport of oxidized sulfur and nitrogen pollutants in East Asia

The long-range transport of oxidized sulfur(sulfur dioxide(SO_2) and sulfate) and oxidized nitrogen(nitrogen oxides(NO_x ) and nitrate) in East Asia is an area of increasing scientific interest and political concern. This paper reviews various published papers, including ground- and satellite-based observations and numerical simulations. The aim is to assess the status of the anthropogenic emissions of SO_2 and NO_x and the long-range transport of oxidized S and N pollutants over source and downwind region. China has dominated the emissions of SO_2 and NO_x in East Asia and urgently needs to strengthen the control of their emissions, especially NO_x emissions. Oxidized S and N pollutants emitted from China are transported to Korea and Japan, due to persistent westerly winds, in winter and spring.However, the total contributions of China to S and N pollutants across Korea and Japan were not found to be dominant over longer time scales(e.g., a year). The source–receptor relationships for oxidized S and N pollutants in East Asia varied widely among the different studies. This is because:(1) the nonlinear effects of atmospheric chemistry and deposition processes were not well considered, when calculating the source–receptor relationships;(2) different meteorological and emission data inputs and solution schemes for key physical and chemical processes were used; and(3) different temporal and spatial scales were employed. Therefore, simulations using the same input fields and similar model configurations would be of benefit, to further evaluate the source–receptor relationships of the oxidized S and N pollutants.     

基于数值模拟和响应面法的PRB设计影响研究

影响PRB设计的因素很多,利用COMSOL Multiphysics软件建立地下水连续PRB的流体流动和溶质运移的数值模型,采用响应面方法研究了PRB与含水层渗透系数的比log K、PRB的位置D及PRB的墙体厚度W对水力停留时间和捕获区域宽度的影响。多元回归分析得到水力停留时间的二次方程模型,方差分析结果显示PK的增加而变小,超过某一值时,并不变化。污染源与PRB距离越近,所需捕获区域宽度越小,墙体的厚度越大;距离越远,所需捕获区域宽度越大,污染范围越广,不利于污染物的治理与控制。设计PRB应用时,需平衡各因素之间的关系,兼顾效率与效益,同时注意安全因子的量化。     

玉米芯为碳源铁屑协同生物麦饭石活化颗粒的硫酸盐还原动力学及其锰离子响应实验

利用聚乙烯醇和饱和硼酸,添加30%SRB污泥、5%玉米芯、2%铁屑和3%麦饭石包埋制备内聚营养源的SRB固定颗粒,将完全活化的SRB颗粒作为研究对象,探究活化颗粒对SO42-反应动力学过程及其对高浓度Mn2+离子响应机制。结果表明:活化颗粒还原SO42-的过程符合一级动力学模型,最大还原速率为94.88 mg/(L·h);高浓度Mn2+可抑制活化颗粒的pH提升能力,延缓碳源的水解速率及SO42-的还原速率,而不会抑制水解过程并延长缓滞期,更不能降低最终去除效果。可见,以玉米芯为碳源的铁屑协同生物麦饭石颗粒处理煤矿酸性废水是有效并可行性的。     

强化内电解预处理制药废水

为进一步提高铁炭内电解法处理制药废水的处理效率,采用添加不同强化剂的方法考察分析强化因子的影响效果。在C加入量10 g/L,铁屑30 g/L,反应时间150 min,pH值7.5的条件下,以不同的盐、金属铜、双氧水作强化剂分别加入反应体系中,检测COD去除效果。实验结果表明：当每升废水中分别加入氯化铜、硫酸锰、硝酸镍、金属铜、双氧水(30%)量为0.324 g、1.51 g、3.66 g、15 g、6 mL时,COD去除率分别为28.89%、44.70%、34.04%、23.45%和24.14%,强化剂的加入有效地提高了废水COD去除效果,也很好地提高了废水可生化性。     

Determination of effects of turbulence flow in a cathode environment on electricity generation using a tidal mud-based cylindrical-type sediment microbial fuel cell

We examined the possibility of harvesting electricity from the surface of a tidal mud flat using a cylindrical-type sediment microbial fuel cell (SMFC), a marine mud battery (MMB), which can be applied in a sea environment where the ebb and flow occur due to tidal difference. In addition, we indirectly investigated the influence of ebb and flow in a lab, using aeration, argon gassing, and by agitating the cathodic solution. The MMBs consisted of cylindrical acrylic compartments containing a nylon membrane, an anode, and a cathode in a single body. The MMBs were stuck vertically into an artificial tidal mud flat such that the anode electrode was in direct contact with the tidal mud surface. As a result, the maximum current and power density generated were 35 mA/m² and 9 mW/m², respectively, thus verifying that it is possible to harvest electricity from the surface of a tidal mud flat using an MMB without burying the anode electrode in the tidal mud. Furthermore, the results of tests using an artificial turbulence flow showed the flow induced by the tidal ebb and flow could allow the performance of MMBs to be enhanced.     

Allelopathic Potential of Switchgrass (Panicum virgatum L.) on Perennial Ryegrass (Lolium perenne L.) and Alfalfa (Medicago sativa L.)

This study investigated allelopathy and its chemical basis in nine switchgrass (Panicum virgatum L.) accessions. Perennial ryegrass (Lolium perenne L.) and alfalfa (Medicago sativa L.) were used as test species. Undiluted aqueous extracts (5 g plant tissue in 50 ml water) from the shoots and roots of most of the switchgrass accessions inhibited the germination and growth of the test species. However, the allelopathic effect of switchgrass declined when extracts were diluted 5- or 50-fold. Seedling growth was more sensitive than seed germination as an indicator of allelopathic effect. Allelopathic effect was related to switchgrass ecotype but not related to ploidy level. Upland accessions displayed stronger allelopathic potential than lowland accessions. The aqueous extract from one switchgrass accession was separated into phenols, organic acids, neutral chemicals, and alkaloids, and then these fractions were bioassayed to test for allelopathic potential. Alkaloids had the strongest allelopathic effect among the four chemical fractions. In summary, the results indicated that switchgrass has allelopathic potential; however, there is not enough evidence to conclude that allelopathic advantage is the main factor that has contributed to the successful establishment of switchgrass on China’s Loess Plateau.