简讯

01.生态环境部:2021年全国PM_2.5平均浓度每立方米要下降0.5微克,生态环境部近日表示,未来我国大气污染防治将重点聚焦PM_2.5和臭氧污染协同改善,2021年全国PM_2.5平均浓度每立方米要下降0.5微克。生态环境部数据显示,2020年,未达标地级及以上城市PM_2.5平均浓度比2015年下降28.8%,全国优良天数比率比2015年上升5.8个百分点,“十三五”约束性指标超额完成。未来环境质量改善目标仍将聚焦PM_2.5和优良天数两方面,重点减排的污染物将从原有的二氧化硫转向VOCs。     

2007年5-6月国内安全事故统计分析

统计了2007年5-6月国内发生的各种安全事故429起,包括矿业事故、交通事故、爆炸事故、火灾、毒物泄露和中毒及其他事故.统计表明,在这些事故中,其他事故最多,占41.26%,其次是交通事故(36.83%)、矿业事故(12.82%)、爆炸事故(5.13%)、毒物泄露和中毒(2.10%)、火灾(1.86%).429起事故共死亡1 213人,伤1 128人,死亡人数的百分比分别为交通事故49.46%、其他事故22.92%、矿业事故18.38%、爆炸事故4.20%、火灾3.38%、泄露中毒1.65%;受伤人数的百分比分别为交通事故58.16%、爆炸事故17.55%、矿业事故9.93%、其他事故7.18%、泄露中毒5.59%、火灾1.60%.     

2007年7-8月国内安全事故统计分析

统计了2007年7-8月国内发生的各种安全事故496起,包括矿业事故、交通事故、爆炸事故、火灾、毒物泄露和中毒及其他事故.统计表明,在这些事故中,其他事故最多,占39.31%,其次是交通事故(36.29%)、矿业事故(13.91%)、毒物泄露和中毒(5.04%)、爆炸事故(3.83%)、火灾(1.61%).496起事故共死亡1 518人,伤1 143人,死亡人数的百分比分别为交通事故47.04%、其他事故23.39%、矿业事故18.05%、爆炸事故5.60%、泄露中毒4.41%、火灾1.52%;受伤人数的百分比分别为交通事故57.39%、其他事故17.94%、矿业事故9.71%、泄露中毒8.40%、爆炸事故5.51%、火灾1.05%.     

肥胖:都是病菌惹的祸?

如今肥胖似乎正成为一种趋势,全世界肥胖人群越来越庞大。世界卫生组织的数据显示,全球超过3亿人属于肥胖人群,另有10亿多人超重。     

Biosorption of cesium（Ⅰ） from aqueous solution by a novel exopolymers secreted from Pseudomonas fluorescens C-2： Equilibrium and kinetic studies

The biosorption characteristics of Cs(I) ions from aqueous solution using exopolymers (PFC02) produced from Pseudomonas fluorescens C-2 were investigated as a function of pH, biosorbent dosage, contact time and initial concentration. pH played a major role in the adsorption process, and the optimum pH for the removal of Cs(I) was 8.0. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the Cs(I) ions by PFC02. The Lagergren first-order, pseudo second-order kinetic and intraparticle diffusion models were used to test the kinetic data. Langmuir model and D-R model fitted the equilibrium data better than the Freundlich isotherm. The monolayer adsorption capacities of PFC02 as obtained from Langmuir isotherm at 25°C was found to be 32.63 mg/g. From the D-R isotherm model, the mean free energy was calculated as 26.73 kJ/mol, indicating that the biosorption of cesium was chemisorption. The biosorption process was rapid, and the kinetic rates were best fitted to the pseudo second-order model, which indicated the biosorption process operated through chemisorption mechanism. FT-IR analysis of PFC02 showed the possible functional groups responsible for cesium adsorption were hydroxyl, carboxyl, carbonyl and sulphonate groups. SEM analysis showed the porous structure of the material while EDX analysis confirmed the adsorption of Cs(I) on PFC02. Cesium adsorbed onto the PFC02 could be desorbed efficiently using 1 mol/L HNO3, and the enrichment factor was 50.0. Furthermore, PFC02 could be reused five times with only about 8.25% regeneration loss. The developed method was successfully utilized for the removal of Cs(I) ions from aqueous solution.     

Estimation and comparison of night-time OH levels in the UK urban atmosphere using two di erent analysis methods

Night-time OH levels have been determined for UK urban surface environments using two methods, the decay and steady state approximation methods. Measurement data from the UK National Environmental Technology Centre archive for four urban sites (Bristol, Harwell, London Eltham and Edinburgh) over the time period of 1996 to 2000 have been used in this study. Three reactive alkenes, namely isoprene, 1,3-butadiene and trans-2-pentene were chosen for the calculation of OH levels by the decay method. Hourly measurements of NO, NO2, O3, CO and 20 VOCs were used to determine night-time OH level using the steady state approximation method. Our results showed that the night-time OH levels were in the range of 1 105–1 106 molecules/cm3 at these four urban sites in the UK. The application of a t-test of these analyses indicated that except Bristol, there was no significant di erence between the OH levels found from the decay and steady state approximation methods. Night-time levels of the OH radical appeared to peak in summer and spring time tracking the night-time O3 levels which also passed through a maximum at this time.     

阿拉巴马大学：推进研究中心

每年,20名航空和机械工程专业的学生可以用8个月时间来设计,建造,和试飞火箭,飞行高度可达1609米。 此前,学生建造了一枚约16公斤重,2．6米长的碳纤维火箭,搭载了先进的数据收集系统。     

基于WebGIS的包头市环境地理信息系统平台搭建

本文首先综述了包头市环境地理信息系统平台的总体结构、功能模块、数据构成等,然后着重阐述EGIS平台下的环保数据构成、异构异地数据集成的关键技术和空间数据库与多元数据库的关联接口,最后论述了建设该平台的设计方法和平台特点。     

国家环境数据共享与服务体系研究

结合我国环境数据共享与服务面临的问题,对国家环境数据共享与服务体系的时代背景、概念和实质、技术框架、主要建设内容等进行了研究。指出国家环境数据共享与服务体系是政府主导建设的环境信息资源网,核心由三级环境数据中心、依托于四级专网的环境数据传输与交换平台以及分别依托于内网、专网和互联网的各级共享服务门户构成。     

自然贮存场自然环境剖面归纳处理

针对某自然贮存场近几年的自然环境因素数据,应用小波分析理论对温度数据的周期分量和随机分量进行了分离.在数据分离的基础上,根据阿仑尼斯方程对年温度数据的周期分量,进行了等效平均,获得以热天、冷天划分的年恒定温度剖面.根据Manson-coffin模型对温度数据的随机分量进行了等效循环处理,最后综合得到贮存场的试验室模拟试...