A metal-OH group modification strategy to prepare highly-hydrophobic MIL-53-Al for efficient acetone capture under humid conditions

A series of highly-hydrophobic MIL-53-Al (MIL = Materials of Institut Lavoisier) frameworks synthesized via decoration of the Al-OH groups by alkyl phosphonic acid were developed as adsorbents for removing acetone from humid gas streams. The newly prepared materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), N₂ adsorption-desorption and thermogravimetric analysis (TGA). Their adsorption behaviors toward acetone vapor under dry and wet conditions were studied subsequently. Results showed that alkyl phosphonic acid was successfully grafted into MIL-53-Al skeleton through coordinating interaction with Al³⁺ generating [email protected]_x (x = 12, 14, 18). The [email protected]_x exhibited similar crystal structure and thermal stability to parent MIL-53-Al. Furthermore, the modified materials showed significantly enhanced hydrophobicity. The water vapor uptake of [email protected]₁₄ decreased by 72.55% at 75% relative humidity (RH). Dynamic adsorption experiments demonstrated that water vapor had almost no effect on the acetone adsorption performance of [email protected]₁₄. Under the condition of 90% RH, the acetone adsorption capacity of [email protected]₁₄ was 102.98% higher than that of MIL-53-Al. Notably, [email protected]₁₄ presented excellent adsorption reversibility and regeneration performance in 10 adsorption-desorption cycles. Taken together, the strategy of metal-OH group modification is an attractive way to improve the acetone adsorption performance over metal-organic frameworks (MOFs) under humid conditions. Besides, [email protected]₁₄ would be deemed as a promising candidate for capturing acetone in high moisture environment.     

论DNA分子标记在家畜遗传多样性保护中的应用

本文就ＤＮＡ分子遗传标记在家畜遗传多样性保护中应用的可行性及途径进行了探讨，提出了家畜遗传多样性标记辅助保护新策略。     

Effect of acid precipitation on leaching of nutritionsand aluminium from forest soils

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基于AHP-MF模型的用户群节水指标体系研究

从分析影响用户群节水的因素及其构成关系入手,根据专家长期节水工作的经验,利用层次分析法对用户群节水指标进行优选,并提出全面的定量化和定性化的层次结构评价模式和总体评价方法.首先构建用户群节水的层次分析结构模型及判断矩阵,应用Matlab6.5计算出各判断矩阵的最大特征值及其特征向量,并检验判断矩阵的一致性,继而确定出各指标的权重;其次,应用Fuzzy统计的方法对陕西2006年度高校用户群的节水情况进行评价,并为节水工作提供建设性意见.     

天津地区大气污染状况和气溶胶硫酸盐的研究

我们于1980—1981年对天津市大气污染物浓度做了同步监测,对天津市大气污染状况,二氧化硫转化为硫酸盐的过程及其对大气能见度的影响做了研究。以超C_i几率和的方法处理数据,研究结果表明,大气污染以早晨最严重,傍晚次之,中午较轻:冬季比夏季污染严重。各种污染物中以硫酸盐对大气能见度的影响最大,总颗粒物次之。当大气相对湿度大于70%时,对大气能见度的影响比较突出。颗粒物中的苯溶物对大气能见度有一定的影响。城市中相对湿度高时硫酸盐浓度大,可能是产生冬季烟雾事件的原因。下风方向的硫酸根浓度与二氧化硫浓度的比值和硫酸根含硫浓度与大气总硫浓度的比值均比上风方向相应的数值高,说明城市燃煤烟气是硫酸盐的来源。城市中硫酸根浓度与二氧化硫浓度的相关系数为0.77,硫酸根与颗粒物浓度的相关系数为0.95。在形成硫酸根的过程中二氧化硫浓度和颗粒物可能有贡献。以一维有源简化模式估算二氧化硫转化为硫酸根的速率常数,约为2.3±1.1%/hr,冬季约1.5%/hr。二氧化硫的迁移距离约为17—340km。     

高级氧化技术机理及在水处理中的应用进展

综述了近年来发展迅速的高级氧化技术，主要包括Fenton法、臭氧氧化法、湿式氧化技术、超临界水氧化法、纳米光催化氧化法电化学催化降解法及超声降解法等。介绍了各种高级氧化技术的基本原理及在废水处理中的应用进展，并对其特点进行了评述。     

203HgCl2在紫贻贝(Mytilus cdulis)体内的累积和结合以及锌对其影响的实验研究

本文研究了紫贻贝（Mytilus edulis）对无机汞²⁰³HgCl₂的累积和结合.实验结果表明:紫贻贝累积汞速度很快,能力很强.用Sephadex G75凝胶层析表明:所有的²⁰³Hg几乎都以生物大分子存在（M.W.>1000）.其中大部分²⁰³Hg的分子量大于50000,小部分分子量在1000—50000之间.本文还讨论了汞的累积机制,并研究了Zn²⁺对于²⁰³Hg累积的影响.     

Land use as a mitigation strategy for the water-quality impacts of global warming: a scenario analysis on two watersheds in the Ohio River Basin

This study uses an integrative approach to study the water-quality impacts of future global climate and land-use changes. In this study, changing land-use types was used as a mitigation strategy to reduce the adverse impacts of global climate change on water resources. The climate scenarios were based on projections made by the Intergovernmental Panel on Climate Change (IPCC) and the United Kingdom Hadley Centre's climate model (HadCM2). The Thornthwaite water-balance model was coupled with a land-use model (L-THIA) to investigate the hydrologic effects of future climate and land-use changes in the Ohio River Basin. The land-use model is based on the Soil Conservation Service's curve-number method. It uses the curve number, an index of land use and soil type, to calculate runoff volume and depth. The ArcView programming language, Avenue, was used to integrate the two models into a geographic information system (GIS). An output of the water-balance model, daily precipitation values adjusted for potential evapotranspiration, served as one of the inputs into the land-use model. Two watersheds were used in the present study: one containing the city of Cincinnati on the main stem of the Ohio River, and one containing the city of Columbus on a tributary of the Ohio River. These cities represent two major metropolitan areas in the Ohio River Basin with different land uses experiencing different rates of population growth. The projected hypothetical land-use changes were based on linear extrapolations of current population data. Results of the analyses indicate that conversion from agricultural land use to low-density residential land use may decrease the amount of surface runoff. The land-use practices which generate the least amount of runoff are forest, low-density residential, and agriculture; whereas high-density residential and commercial land-use types produce the highest runoff. The hydrologic soil type present was also an important factor in determining the amount of runoff and non-point-source pollution. A runoff-depth matrix and total nitrogen matrix were created for Cincinnati and Columbus to describe possible land-use mitigation measures in response to global climate change. The differences in Cincinnati and Columbus were due to differences in geographic location, air temperature, and total runoff. The results of this study may be useful to planners and policy makers for defining the possible impacts of future global climate and land-use changes on water resources.     

以监测预报工作为导向推进数字化监测教学

地震预测的发展方向,是从协同的观点,多层面地统筹考虑地震监测体系的建设,实现基础研究与实际地震预测工作的结合.本文从如何利用原有监测资料、连续前兆监测数据处理系统的建立、前兆监测体系数据报送体系等地震监测工作环节,分析地震监测教学如何与监测工作方向相一致,并对教学改革如何结合台站技术人员更新提出了几点看法.     

A regional environmental management information system for Chinese EPA—the system analysis and design

REMIS is one of key research projects sponsored by the central government. It is recommended to regional EPAs as a main tool of the environmental management. REMIS simulates the functions of the regional EPAs and aimed to improve their management level. The national environmental management information system will base on REMIS.Functional analysis is the kernel of the REMIS system analysis. Data and data flow analysis are used to support the functional analysis.Investigations on the functions of the local EPAs of eight provinces and 12 cities have been taken. The functions were carefully sorted. Modular design method was used in system analysis and system design.The system analysis included functional analysis, data analysis and data flow analysis. The system design is based on the system analysis. HIPO diagram of each modular, data base structure, menu design, selection of hardware and software environment were the main items of the system design.