Pb2+、Cu2+、Cd2+在胡敏酸上的吸附和竞争吸附

研究了金属离子Pb2+、Cu2+、Cd2+在胡敏酸上的单一吸附和两两组分竞争吸附.结果表明,总体胡敏酸对Cu2+、Pb2+的吸附明显强于Cd2+.Freundlich方程对Pb2+、Cd2+单一金属离子吸附等温线的拟合呈极显著关系,Langmuir方程为胡敏酸吸附Cu2+的最佳拟合方程.Pb2+、Cu2+、Cd2+的两两组分竞争吸附表明,胡敏酸对3种离子均具有"选择性吸附",竞争能力从大到小依次为Pb2+、Cu2+、Cd2+.     

风宜长物放眼量——安防企业须有创新战略眼光

创新精神和创新意识 提到创新就不得不提到经济学家Joseph Alois Schumpeter.早在1912年,他就在德文著作<经济发展理论>中,首次提出了创新的概念.     

Variations in speciated emissions from spark-ignition and compression-ignition motor vehicles in California's south coast air basin

The U.S. Department of Energy Gasoline/Diesel PM Split Study examined the sources of uncertainties in using an organic compound-based chemical mass balance receptor model to quantify the contributions of spark-ignition (SI) and compression-ignition (CI) engine exhaust to ambient fine particulate matter (PM2.5). This paper presents the chemical composition profiles of SI and CI engine exhaust from the vehicle-testing portion of the study. Chemical analysis of source samples consisted of gravimetric mass, elements, ions, organic carbon (OC), and elemental carbon (EC) by the Interagency Monitoring of Protected Visual Environments (IMPROVE) and Speciation Trends Network (STN) thermal/optical methods, polycyclic aromatic hydrocarbons (PAHs), hopanes, steranes, alkanes, and polar organic compounds. More than half of the mass of carbonaceous particles emitted by heavy-duty diesel trucks was EC (IMPROVE) and emissions from SI vehicles contained predominantly OC. Although total carbon (TC) by the IMPROVE and STN protocols agreed well for all of the samples, the STN/IMPROVE ratios for EC from SI exhaust decreased with decreasing sample loading. SI vehicles, whether low or high emitters, emitted greater amounts of high-molecular-weight particulate PAHs (benzo[ghi]perylene, indeno[1,2,3-cd]pyrene, and coronene) than did CI vehicles. Diesel emissions contained higher abundances of two- to four-ring semivolatile PAHs. Diacids were emitted by CI vehicles but are also prevalent in secondary organic aerosols, so they cannot be considered unique tracers. Hopanes and steranes were present in lubricating oil with similar composition for both gasoline and diesel vehicles and were negligible in gasoline or diesel fuels. CI vehicles emitted greater total amounts of hopanes and steranes on a mass per mile basis, but abundances were comparable to SI exhaust normalized to TC emissions within measurement uncertainty. The combustion-produced high-molecular-weight PAHs were found in used gasoline motor oil but not in fresh oil and are negligible in used diesel engine oil. The contributions of lubrication oils to abundances of these PAHs in the exhaust were large in some cases and were variable with the age and consumption rate of the oil. These factors contributed to the observed variations in their abundances to total carbon or PM2.5 among the SI composition profiles.     

迷宫式除尘器在木工车间中的应用

(一)概述福州第一脱胎漆厂,过去厂里许多木工专用机床,如带锯机、平压刨床、截锯机,以及一些脱胎漆器生产专用木工机床均未装上吸尘罩及防尘设施,车间粉尘锯末到处飞扬,严重     

北美的深部气田

<正> 现在人们已经认识到,大气田可以产于美国和加拿大的许多陆上盆地的深部向斜构造中。这些气田不全是常规的构造圈闭或地层圈闭。这些气田的空间分布范围很大,甚至极大,有些气田的分布面积超过16000km~2。这些气田的可采储量一般也很大,从几个兆 ft~3(1ft     

夏末秋初吃出健康

饮食宜清淡 炎夏和初秋的饮食应以清淡质软、易于消化为主,少用厚味及辛辣上火之物.清淡饮食能清热、防暑、敛汗、补液,还能增进食欲.多吃新鲜蔬菜瓜果,既可满足所需营养,又可预防中暑.主食以稀为宜,如绿豆粥、莲子粥、荷叶粥等.还可适当饮些清凉饮料,如酸梅汤、菊花茶等.但冷饮要适度,不可偏嗜寒凉之品,否则会伤阳而损身.还可吃些醋,既能生津开胃,又能抑制、杀灭病菌,预防肠道传染病.     

湖南大地景观安全规划及生态学效益分析——沿河两岸分级截流分散蓄水的治水模式

针对湖南近年来频繁发生严重水、旱灾害的实际，从综合分析湖南地质环境和水系现状入手，结合目前农村产业结构调整的方向和未来城市化进程中发展生态旅游业的需要，以优化湖南整体生态环境为目标，从大地景观安全和可持续发展的角度提出了沿河两岸分级截流分散蓄水的治水模式，详细分析了由此可能产生的景观生态学效益。     

电子束半干法烟气净化技术

电子束烟气净化技术由于能够同时脱除烟气中的SO2和NOx而得到世界各国环保界的重视,传统的电子束烟气净化技术在工业应用中存在能耗高,副产品黏结严重,工作可靠性低等问题,新型电子束半干法烟气净化技术解决了传统工艺在工业化应用中存在的问题,可以在较小的辐射剂量下获得更为理想的烟气净化效果,提高了系统的工作可靠性,是一项工业应用前景十分广阔的环保技术.     

厌氧折流板反应器处理生活污水的运行特性

以厌氧消化污泥作为厌氧折流板反应器ABR的接种污泥,研究恒温(35℃)条件下ABR处理生活污水的启动和运行特性。实验结果表明,ABR反应器仅用了39 d就完成初次启动,COD去除率一直稳定在60%左右。在以后运行的5个阶段里,即当水力停留时间为4~10 h,容积负荷为1.17~2.9 kg COD/m3.d,反应器对COD的平均去除率基本稳定在70.49%~80.2%;并且当HRT=7 h,VRL=1.612 kg COD/m3.d时,反应器对COD的去除率平均高达80.2%,平均COD出水低于100 mg/L。在实验过程中(除启动阶段外),反应器出水碱度均远远大于进水碱度,VFA均在1.5 mmol/L以下。     

通信信号调制识别技术研究

针对通信信号调制方式识别问题,提出了采用高阶累积量与信号瞬时特征相结合提取通信信号特征参数的方法,并讨论了利用获得的特征参数进行模拟、数字通信信号调制方式识别的方法和过程。实验结果表明,该方法对通信信号调制方式有很好的识别效果。