城区热电厂灰水系统简易改造设计方案

作为大气污染控制和节能的有效手段，城区热电厂的数量和规模都在增加，针对目前城区热电厂灰水系统普遍存在的问题和制约因素，对系统简易改造的方案设计方法进行了研究。     

碱厂废碱液在湿式烟气脱硫工艺中应用的实验研究

纯碱厂在生产过程中要排放许多废碱液，如果用作烟气脱硫剂，不仅降低了脱硫费用，而且消除报废碱液的主要成分，介绍了旋流板塔式除尘脱硫装置的结构和工作原理，探讨了影响用废碱液除尘脱硫效果的主要因素，并找出了较好的操作条件。实验结果表明：废认在该装置上脱硫和除尘效果均达到国内外同类装置的水平，同量，解决了因为废碱液带来的水污染。除尘脱硫装置结构简单，基建费用和运行费用低，是一项值得推广的技术。     

A comparison of measured and simulated ozone concentrations in the rural areas of the eastern United States during summer 1995

The recent regulatory actions toward a longer-term (i.e., 8-hr) average ozone standard have brought forth the potential for many rural areas in the eastern United States to be in noncompliance. However, since a majority of these rural areas have generally few sources of anthropogenic emissions, the measured ozone levels primarily reflect the effects of the transport of ozone and its precursor pollutants and natural emissions. While photochemical grid models have been applied to urban areas to develop ozone mitigation measures, these efforts have been limited to high ozone episode events only and do not adequately cover rural regions. In this study, we applied a photochemical modeling system, RAMS/UAM-V, to the eastern United States from June 1-August 31, 1995. The purpose of the study is to examine the predictive ability of the modeling system at rural monitoring stations that are part of the Clean Air Status Trends Network (CASTNet) and the Gaseous Pollutant Monitoring Program (GPMP). The results show that the measured daily 1-hr ozone maxima and the seasonal average of the daily 1-hr ozone maxima are in better agreement with the predictions of the modeling system than those for the daily 8-hr ozone maxima. Also, the response of the modeling system in reproducing the measured range of ozone levels over the diurnal cycle is poor, suggesting the need for improvement in the treatment of the physical and chemical processes of the modeling system during the nighttime and morning hours if it is to be used to address the 8-hr ozone standard.     

Breeding biology of Megalops cyprinoides from Visakhapatnam coast

Studies on stages of maturity, gonado-somatic indices and breeding cycle from two different habitats viz., the polluted Harbour Waters and the unpolluted Yerragedda Mouth revealed that M. cyprinoides breeds twice a year i.e., during Jan-Jul and Dec-Jan. Size at first maturity was 18 cm. in females and 19 cm. in males at both the stations. Sex ratio was 1:1 at the polluted station and 1:1.1 at the unpolluted station indicating a slight domination of females.     

Design of aquifer remediation systems: (1) describing hydraulic structure and NAPL architecture using tracers

Aquifer heterogeneity (structure) and NAPL distribution (architecture) are described based on tracer data. An inverse modelling approach that estimates the hydraulic structure and NAPL architecture based on a Lagrangian stochastic model where the hydraulic structure is described by one or more populations of lognormally distributed travel times and the NAPL architecture is selected from eight possible assumed distributions. Optimization of the model parameters for each tested realization is based on the minimization of the sum of the square residuals between the log of measured tracer data and model predictions for the same temporal observation. For a given NAPL architecture the error is reduced with each added population. Model selection was based on a fitness which penalized models for increasing complexity. The technique is demonstrated under a range of hydrologic and contaminant settings using data from three small field-scale tracer tests: the first implementation at an LNAPL site using a line-drive flow pattern, the second at a DNAPL site with an inverted five-spot flow pattern, and the third at the same DNAPL site using a vertical circulation flow pattern. The Lagrangian model was capable of accurately duplicating experimentally derived tracer breakthrough curves, with a correlation coefficient of 0.97 or better. Furthermore, the model estimate of the NAPL volume is similar to the estimates based on moment analysis of field data.     

Superior CO2 uptake on nitrogen doped carbonaceous adsorbents from commercial phenolic resin

In this study, N-doped porous carbons were produced with commercial phenolic resin as the raw material, urea as the nitrogen source and KOH as the activation agent. Different from conventional carbonization-nitriding-activation three-step method, a facile two-step process was explored to produce N-incorporated porous carbons. The as-obtained adsorbents hold superior CO₂ uptake, i.e. 5.01 and 7.47 mmol/g at 25?°C and 0?°C under 1 bar, respectively. The synergistic effects of N species on the surface and narrow micropores of the adsorbents decide their CO₂ uptake under 25?°C and atmospheric pressure. These phenolic resin-derived adsorbents also possess many extremely promising CO₂ adsorption features like good recyclability, quick adsorption kinetics, modest heat of adsorption, great selectivity of CO₂ over N₂ and outstanding dynamic adsorption capacity. Cheap precursor, easy preparation strategy and excellent CO₂ adsorption properties make these phenolic resin-derived N-doped carbonaceous adsorbents highly promising in CO₂ capture.