High performance of multi-layered alternating Ni–Fe–P and Co–P films for hydrogen evolution

Judiciously engineering the electrocatalysts is attractive and challenging to exploit materials with high electrocatalytic performance for hydrogen evolution reaction. Herein, we successfully perform the interface engineering by alternately depositing Co–P and Ni–Fe–P films on nickel foam, via facile electroless plating and de-alloying process. This work shows that there is a significant effect of de-alloying process on alloy growth. The electronic structure of layered alloys is improved by interface engineering. The multilayer strategy significantly promotes the charge transfer. Importantly, the Co–P/Ni–Fe–P/NF electrode fabricated by interface engineering exhibits excellent electrocatalytic hydrogen evolution activity with an overpotential of 43.4 mV at 10 mA cm-2 and long-term durability for 72 h in alkaline medium (1 mol L-1 KOH). The innovative strategy of this work may aid further development of commercial electrocatalysts.     

The effects of air pollution on the lung cancer mortality in rural areas of eastern China: a multi-region study

Environmental Science and Pollution Research - Recently, the burden of lung cancer (LC) has attracted global attention. Meanwhile, LC has become the leading cause of death in China. Many studies...     

Does more voluntary environmental information disclosure cut down the cost of equity: heavy pollution industries in China

Environmental Science and Pollution Research - Examining the coexisting policies for mandatory and voluntary disclosure of environmental information, this paper focuses on the unique background for...     

冬季大气中苯系物污染特征及人体暴露水平分析

2007年冬季对乌鲁木齐市空气中苯系物(BTX)进行了网格布点监测,并用气相色谱仪进行样品分析. 结果表明:冬季大气中苯(B)、甲苯(T)和二甲苯(X)的质量浓度分别为5.62~20.57,3.40~122.82和2.20~129.15 μg/m3. 与欧洲标准相比,该地区ρ(苯)较高,且部分地区高于欧洲控制标准;而ρ(甲苯)和ρ(二甲苯)较低,达到欧洲目标限值水平. 苯系物质量浓度和空间分布特点较显著,ρ(甲苯)与ρ(二甲苯)的空间分布较为一致,但与ρ(苯)的分布特点不同. 最后通过对苯系物的人口加权大气污染暴露水平进行分析可知,乌鲁木齐市ρ(苯),ρ(甲苯)和ρ(二甲苯)的污染暴露水平在空间分布上较为均匀,但人口密度空间分布不均匀,故与ρ(苯)分布没有显著的相关性. 城区的ρ(苯),ρ(甲苯)和ρ(二甲苯)的人口加权平均值均略低于全市人口加权平均值,说明虽然城区人口密度较高,但其ρ(苯),ρ(甲苯)和ρ(二甲苯)的人口加权污染暴露水平相对较低.      

艾比湖流域不同植物群落土壤呼吸研究

利用开路式土壤碳通量测量系统LI-8100测定艾比湖流域4种植物群落土壤呼吸速率日变化,分析土壤温度、湿度和气温以及空气相对湿度对土壤呼吸速率的影响.结果表明:胡杨、梭梭、芦苇和盐节木4种植物群落的土壤呼吸速率日变化基本呈单峰曲线.胡杨、梭梭和盐节木群落的土壤呼吸速率与地上10 和150 cm处气温均表现为极显著相关.除芦苇群落外,各植物群落土壤呼吸速率与不同深度土壤温度呈极显著负相关.除沙地梭梭群落外,胡杨、盐渍地梭梭、芦苇和盐节木群落的土壤呼吸速率与地上10和150 cm处的空气相对湿度均呈极显著负相关.不同植物群落土壤呼吸速率与土壤湿度呈极显著负相关.多元逐步回归拟合的回归模型均达极显著水平,由土壤温度和湿度共同拟合出的回归模型能够解释土壤呼吸速率变化87%以上的原因.不同植物群落土壤呼吸差异原因的分析显示,细菌、真菌、放线菌以及根系干质量不是造成植物群落土壤呼吸差异的主要原因.      

减压塔规整填料腐蚀现状与防护

介绍了减压塔规整填料腐蚀的现状,阐述了介质温度、流速、腐蚀介质种类和填料尺寸等因素对规整填料腐蚀的影响,提出了改变工艺、加注缓蚀剂、改变材质和加强腐蚀检测等防护措施。     

生态适宜的城市发展空间分析方法与案例研究

综合运用生态功能区划方法和土地建设适宜性分析技术,基于地理信息系统平台建立了生态适宜的城市发展空间区域(生态主导功能区)的划分方法,依据生态保护原则和土地开发适宜度,将城市生态主导功能区划分为禁止、限制、优化和重点开发区4种类型.介绍了该方法在大连市的应用.结果表明,大连市禁止、限制、优先和重点开发区面积分别占全市域土地面积的56%、19%、12%和13%.     

集约化露天菜地表层土壤盐分累积特征及消长规律

以广东省佛山市南海区为例,研究了集约化露天菜地表层土壤盐分的累积状况和离子组成,对盐分的季节性消长规律及其变化原因进行了深入分析.结果表明:2006年春季土壤盐分的累积情况较为严重,5个集约化露天菜地样点中有3个样点(1、2、4号)的表层土壤盐分浓度较高,全盐质量分数超过1.0 g·kg-1,已达到次生盐渍化的标准,其中又以2号样点(菜场)最为突出,伞盐质量分数高至2.42 g·kg1;2006年春季到夏季为脱盐阶段,土壤盐分浓度下降明显;2006年夏季到秋冬季变化幅度不大.土壤盐分浓度的变化与降雨量有密切关系,虽然2006年降雨偏多,但佛山市南海区农业集约化水平较高,部分菜地连年种植蔬菜、复种指数极高、化肥施用量偏大,从而在遇到干早年份和季节,集约化露天菜地土壤仍有发生次生盐渍化的风险.土壤盐分的离子组成上,阳离子以Ca2 为主,占全盐质景分数的11.0%～24.1%;阴离子以NO3-和SO42-为主,分别占全盐质量分数的8.9%～31.0%和10.9%～45.7%.研究结果可为控制土壤盐分累积、提高蔬菜生产能力及品质、保护和合理利用耕地资源,提供参考资料.     

Evaluation of municipal sewage treatment systems for pollutant removal efficiency by measuring levels of micropollutants

In order to evaluate the municipal sewage treatment systems used at Harbin municipal sewage treatment plant for their pollutant removal efficiency, raw sewage and effluent samples at different treatment stages from the sewage treatment systems were taken, priority pollutants (PPs) were identified and quantified using gas chromatography-mass spectrometry (GC-MS) and inductively coupled plasma-atomic emission spectrograph (ICP-AES). The test results indicated that there were one hundred and fifty species of organic pollutants identified in the raw sewage sample, and only ten species of PPs in all the sewage samples. The levels of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di-n-octyl phthalate (DnOP) in the sewage samples were 0.779-0.111 microg l(-1), 1.977-0.022 microg l(-1), 6.411-2.194 microg l(-1) and 7.152-2.953microg l(-1), respectively, and most of these phthalate esters (PAEs) were removed through anaerobic/aerobic (A/O) process; The levels of alachlor, acetochlor, atrazine were 0.074-0.021 microg l(-1), 0.160-0.096 microg l(-1) and 0.238-0.184 microg l(-1), respectively, and the total removal efficiency of atrazine was poorest through the sewage treatment systems. The levels of Cu, Cr, Se, Hg, Ni and Zn were 0.0030-0.2327 mg l(-1). It is therefore concluded from these results that the sewage treatment systems were efficient in removing most of the organic and inorganic compounds in this study, and so, the discharged effluent could cause little of the secondary pollution of the aquatic environment.     

垃圾填埋场渗滤液浓缩液高级氧化组合技术研究

以深圳市某生活垃圾填埋场渗滤液纳滤浓缩液为研究对象,采用"混凝沉淀+高级氧化+A/O"组合技术处理浓缩液.结果表明:混凝沉淀对浓缩液COD、总氮的去除效率分别为62％、48％;高级氧化对混凝沉淀出水COD、色度去除效率分别为71％、99％,对总氮无明显去除效果;A/O深度处理工艺对高级氧化出水COD、总氮平均去除效率分...