大连星海湾水质预测

建设马栏河污水处理厂是改善大连市南部沿海环境的重要措施。本文运用浅海潮波方程和平流扩散方程进行海域水质预测,结果表明：该污水处理厂建成后,星海湾海域水质将有很大好转,达到国家二级标准。     

Ag-AgIO3改性BiOI光催化剂湿法脱除气态单质汞

采用沉积沉淀-光还原法制备了不同AgIO₃含量的BiOI光催化剂,利用X射线衍射、N₂吸附-脱附、扫描电子显微镜、X射线光电子能谱、紫外-可见漫反射光谱和电子自旋共振对其物理化学结构进行表征,在光催化反应器上研究了AgIO₃负载量、光照、溶液温度、pH值、SO₂和NO对气态单质汞（Hg⁰）去除性能的影响.结果表明,与BiOI相比,Ag-AgIO₃改性后光催化剂的脱汞性能大幅提高.当AgIO₃负载量为4wt.%时,光催化剂的脱汞效率高达98%.与NO相比,SO₂对脱汞性能的抑制作用更大.由于Ag和AgIO₃在BiOI表面的高度分散性,Ag-AgIO₃（4%） BiOI的可见光吸收性能明显提高.荧光灯辐照与Ag-AgIO₃/BiOI光催化剂协同会产生大量的活性物种.在Ag-AgIO₃/BiOI光催化剂的高效脱汞体系中,超氧阴离子自由基（·O₂^-）为最主要的活性物质,而空穴（h⁺）和羟基自由基（·OH）次之.     

嗜热膜生物反应器烟气同时脱硝脱汞研究

采用嗜热膜生物反应器(TMBR)同时处理含NO和Hg0的烟气,结果发现,该反应器可实现100 d的长期稳定运行,NO和Hg0去除效率分别可达87.9%、82.4%.适宜运行条件为:喷淋量为60 m L·min~(-1),p H为6.5~8.0,气体停留时间GRT为9.3 s,COD/TN为2~4.同时,采用16S r DNA分析了TMBR微生物群落.结果表明,在属类别上优势菌种是Ureibacillus和Pseudoxanthomonas.Pseudoxanthomonas、Hydrogenophaga、Thauera、Bacillus、Paracoccus、Comamonas、Pseudomonas、Nitrosovibrio、Ochrobactrum属于脱硝类菌属;Pseudomonas和Halomonas与Hg2+转化有关.Pseudomonas同时具有反硝化和还原汞化合物能力.     

载溴石油焦脱除烟气痕量Hg0的动力学机理

采用化学-机械溴化法对废弃物石油焦进行改性,制得的载溴石油焦吸附剂用来脱除燃煤烟气中的痕量Hg⁰.通过比表面积及孔径分析（BET）、X射线衍射（XRD）和X-射线光电子能谱（XPS）对石油焦载溴前后进行表征和分析,发现石油焦中的有机硫促进了溴的负载,且负载方式为化学吸附.通过固定床脱汞试验,并应用4种动力学模型对初始汞浓度梯度和反应温度梯度下的实验数据进行拟合分析,结果表明：温度在150℃时,载溴石油焦的汞吸附效果最优;增加烟气中痕量Hg⁰浓度能提高载溴石油焦的汞吸附速率和单位累积汞吸附量;描述化学吸附的Elovich动力学模型的拟合相关系数达到0.9999以上,说明化学吸附在载溴石油焦脱汞过程中起主导作用.     

Particles and porous tablets based on Fe0/ZSM-5 composites prepared by ball-milling for heavy metals removal: Dissolved Fe2 +, pH, and mechanism

Novel, low-cost Fe~0/ZSM-5-based particles and porous tablets were prepared by a ballmilling method and used for the removal of Pb~(2+) in solution. Solid-phase characterization by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy(SEMEDS) and transmission electron microscopy(TEM) revealed that the Fe0 microparticles were evenly loaded and tightly immobilized on the surface of ZSM-5 because of the extrusion/welding impact during ball-milling. For different Pb~(2+) concentrations, batch experiments indicated that the removal of Pb~(2+) increased with the decline of dissolved Fe2+and p H value in the solution for particles; opposite results were obtained for the tablets. The differences in the contact between both materials and Pb~(2+) were the main factor controlling Pb~(2+) removal in the solution. Investigation into the effect of initial p H value revealed that high p H reduced the number of electrons released from Fe corrosion. Consequently, low levels of removed Pb~(2+) and dissolved Fe~(2+) were synchronously observed. Also, simulated electroplating wastewater was treated using the prepared particles and porous tablets,and the removal order of Pb~(2+) Cr~(6+) Cu~(2+)≈ Cd~(2+) was observed. The Fe~0/ZSM-5 particles and tablets prepared through ball-milling show potential as materials for treatment of Pb~(2+) and other toxic metals.     

MHC, health, color, and reproductive success in sand lizards

0.gif" alt="ldquo" align="MIDDLE" BORDER="0">Good genes0"> are genetic elements that contribute to lifetime reproductive success, regardless of an individual0">s additional genotype. Their existence is debated, and most work has targeted their viability benefits to the offspring of choosy females. In the present study, we analyze a case of potential good genes effects in adult male sand lizards (Lacerta agilis). We show that males with a particular RFLP (Restriction Fragment Length Polymorphism) MHC genotype (O-males), as opposed to those that lack this genetic element (NO-males), have less ectoparasites under increasing physiological stress (indexed by baseline corticosterone level), and are not constrained by parasites at production of status coloration. Furthermore, O-males are more successful at mate acquisition and guard their partners longer. Ultimately, they have a higher genetic reproductive success as assigned by microsatellites.Communicated by W. Cooper     

A Fine-Scale <Emphasis Type="Italic">k</Emphasis>−ε Model for Atmospheric Flow over Heterogeneous Landscapes

A multi-purpose model for small-scale atmospheric flows over heterogeneous landscapes is being developed. The aim of this research is to build a tool able to predict the dynamical (wind, turbulence) and diffusive (gases, particles) fields over landscapes characterised by heterogeneous plant cover. In its present stage of development the model is based on the numerical integration of neutral atmospheric flow equations, using an energy-dissipation closure scheme and over a domain that may include vegetation layers. Three validation cases of the model are presented: (i) response of the airflow to a change in surface roughness; (ii) airflow within and above a horizontally homogeneous plant canopy; (iii) airflow over two complex forest-to-clearing and clearing-to-forest transitions. All simulations provide results in good agreement with the experimental data, except for turbulent kinetic energy just after a clearing-to-forest transition. This result is not surprising for a statistical k013;0"> model in a flow region characterised by strong distorsion and intermittent turbulence. However the overall good performance of the model is promising for environmental research at fine scales over heterogeneous landscapes.     

Degradation of the herbicide imazapyr by Fenton reactions

The degradation of the herbicide imazapyr has been carried out by three advanced oxidation processes involving iron ions as catalysts: Fenton0">s reagent, photo-Fenton and electro-Fenton. We show that all processes are rapid and efficient. The kinetic rate constant was found to be k=5.4×10⁹ M^013;1 s^013;1. The mineralization of imazapyr is almost complete using the photo-Fenton and electro-Fenton processes.     

Ultrastructural and chemical characterization of egg surface of honeybee worker and queen-laid eggs

Summary. Worker policing in honeybees predicts the evolution of a mechanism to discriminate between queenand worker-born eggs. Although it has been postulated that this discrimination is based on an egg recognition pheromone, neither the chemistry nor the glandular source were elucidated. To verify whether egg discrimination might be based on structural differences, we compared the ultrastructure surface of queen-laid diploid and haploid eggs to that of worker-laid eggs using SEM. Only small differences between the different types of eggs were found. Thus, at least based on the fine structure of the egg surface, queen eggs are indistinguishable from worker-laid eggs.To explore the chemosensory hypothesis for egg discrimination, we conducted a detailed comparative chemical analysis of the different egg types. The coating of all egg types was dominated by linear alkanes, but queen eggs, diploid and haploid, differed from those of workers on two accounts: 1. The diversity of compounds found on queenlaid eggs was much greater than found on worker-laid eggs, mainly due to the number of hydrocarbons. 2. Acetates of some fatty alcohols, alkenes and especially monomethylalkanes were characteristic to queen eggs. The origin of the two latter substances and the acetates is still unknown. Whether these compounds constitute the signal that enables police workers to discriminate between queen- and workerborn eggs remains to be investigated.     

The degradation of gel-spun poly(β-hydroxybutyrate) “wool”

The apparent biodegradability and biocompatibility of the microbially produced polyester, poly(0">-hydroxybutyrate) (PHB), has been the focus of much research by a number of authors with regard to its potential for use in packaging and medical implantation devices. PHB has recently been produced by gel-spinning into a novel form, with one possible application being as a wound scaffolding device, designed to support and protect a wound against further damage while promoting healing by encouraging cellular growth on and within the device from the wound surface. This new nonwoven form combines a large volume with a low mass, has an appearance similar to that of 0.gif" alt="ldquo" align="MIDDLE" BORDER="0">cotton wool,0"> and has been called 0.gif" alt="ldquo" align="MIDDLE" BORDER="0">wool0"> because of this similarity. The hydrolytic degradation of this wool was investigated in an accelerated model of pH 10.6 and temperature 70°C. It was determined that the PHB wool gradually collapsed during degradation. The surface area-to-volume ratio was concluded to be a primary influencing factor. Degradation was characterized by a reduction in the glass transition temperatures and melting points and a fusion enthalpy peak of maximum crystallinity, (88%), which coincided with the point of matrix collapse.