电感耦合等离子体质谱法在环境监测中的应用

针对ICP-MS技术的使用特点及其近年来在环境监测领域的应用进行综合阐述，并对ICP-MS技术的发展前景作出简单的评述。     

新技术革命对环境的影响及环境科学未来的研究方向

阐述了人类在不同阶段所面临的不同环境问题和未来新技术革命对环境的可能影响，介绍了环境科学随着环境问题的变化而不断发展变化的过程，指出在新技术革命时代环境科学所面临的未来研究课题及任务。     

浅谈音乐与体育之缘

音乐与体育作为人类社会独特的文化现象,在不同时期以各种形式相互融合,共同构成人类自身情感的表达方式,成为“世界语言”。现代社会,音乐以其特有的审美、教育、娱乐功能对社会的进步和发展起着积极的作用。尤其是音乐与现代奥运会结合,传承了奥林匹克精神,扩大奥运会的影响,展示了民族的文化,让我们真实地感受到一种前所未有的改变世界的力量。     

Characterizing ionic species in PM2:5 and PM10 in four Pearl River Delta cities, South China

PM_(2.5)and PM_(10)samples were collected at four major cities in the Pearl River Delta(PRD),South China,during winter and summer in 2002.Six water-soluble ions,Na~ ,NH_4~ ,K~ ,Cl~-,NO_3~- and SO_4~(2-)were measured using ion chromatography.On average,ionic species accounted for 53.3% and 40.5% for PM_(2.5)and PM_(10),respectively in winter and 39.4% and 35.2%,respectively in summer. Secondary ions such as sulfate,nitrate and ammonium accounted for the major part of the total ionic species.Sulfate was the most abundant species followed by nitrate.Overall,a regional pollution tendency was shown that there were higher concentrations of sulfate, nitrate and ammonium in Guangzhou City than those in the other PRD cities.Significant seasonal variations were also observed with higher levels of species in winter but lower in summer.The Asian monsoon system was favorable for removal and diffusion of air pollutants in PRD in summer while highly loading of local industrial emissions tended to deteriorate the air quality as well.NO_3~-/SO_4~(2-) ratio indicated that mobile sources have considerably contribution to the urban aerosol,and stationary sources should not be neglected. Besides the primary emissions,complex atmospheric reactions under favorable weather conditions should be paid more attention for the control of primary emission in the PRD region.     

鄱阳湖湿地现状问题与未来趋势

近年来鄱阳湖秋冬季水文呈干枯态势,湿地生态系统及其关键因子也发生了变化。如何合理保护和利用鄱阳湖湿地引起各方关注。系统综述了鄱阳湖湿地生态系统在水文、江湖关系、水质、水鸟栖息地、渔业资源等方面存在的问题,梳理了引起这些问题的外部和内部因素。针对"一切照常"和"水位调控"两种情景,预测了湿地未来的变化趋势,并指出了当前研究中的不确定性问题。研究认为:鄱阳湖秋冬季的低枯水位,对水质、湿地植被、水鸟栖息地以及鱼类食物资源和"三场"(即:产卵场、洄游通道、索饵场)产生了一定不利影响。建议通过模型模拟和情景预测来分析不同调控方案的影响效果,优化调控方案、将生态系统的负面影响降到最低。     

构建人类命运共同体、应对气候变化与生态文明建设

全球气候变化给人类社会文明带来严峻挑战,需要人类社会采取共同措施和行动积极应对。应对全球气候变化是当今世界最能体现人类共同命运的领域,深度参与并积极推动全球气候治理体系改革和建设是中国推动构建人类命运共同体的重要实践,也是生态文明理论和实践的重要方面。应对气候变化是我国生态文明建设的重要内容和内在要求;以共同价值理念构建人类命运共同体,凝聚各国力量携手合作应对全球气候变化,是全球生态文明建设和构建人类命运共同体的具体实践,也为应对全球气候变化提供了良好载体和国际平台。文章通过分析可知,应对气候变化、生态文明建设与构建人类命运共同体三者之间,呈现出相互促进、和谐共生的"三位一体"特征;人与自然共生的生命共同体是前提条件,人类的任何实践活动都要以自然生态系统为基础和前提;人类命运共同体在整合各国力量方面,为生态文明建设提供了社会基础;生态文明包容各国文明,凝聚价值共识,成为生命共同体和人类命运共同体的价值导向。中国倡导人类命运共同体理念,是全球生态文明和人类命运共同体的积极倡导者、推动者和践行者,既为应对全球气候变化提供了价值基础,也提供了强有力的实践支撑;应对气候变化是全球生态文明建设和人类命运共同体构建的生动实践。因此,加强生态文明建设和构建人类命运共同体,为全球应对气候变化提供了理论基础和国际平台,也将为全球可持续发展贡献中国智慧和中国案例。     

WATER QUALITY MODELING OF ALTERNATIVE AGRICULTURAL SCENARIOS IN THE U.S. CORN BELT1

ABSTRACT: Simulated water quality resulting from three alternative future land‐use scenarios for two agricultural watersheds in central Iowa was compared to water quality under current and historic land use/land cover to explore both the potential water quality impact of perpetuating current trends and potential benefits of major changes in agricultural practices in the U.S. Corn Belt. The Soil Water Assessment Tool (SWAT) was applied to evaluate the effect of management practices on surface water discharge and annual loads of sediment and nitrate in these watersheds. The agricultural practices comprising Scenario 1, which assumes perpetuation of current trends (conversion to conservation tillage, increase in farm size and land in production, use of currently‐employed Best Management Practices (BMPs)) result in simulated increased export of nitrate and decreased export of sediment relative to the present. However, simulations indicate that the substantial changes in agricultural practices envisioned in Scenarios 2 and 3 (conversion to conservation tillage, strip intercropping, rotational grazing, conservation set‐asides and greatly extended use of best management practices (BMPs) such as riparian buffers, engineered wetlands, grassed waterways, filter strips and field borders) could potentially reduce current loadings of sediment by 37 to 67 percent and nutrients by 54 to 75 percent. Results from the study indicate that major improvements in water quality in these agricultural watersheds could be achieved if such environmentally‐targeted agricultural practices were employed. Traditional approaches to water quality improvement through application of traditional BMPs will result in little or no change in nutrient export and minor decreases in sediment export from Corn Belt watersheds.     

Modified titanium oxide (TiO2) nanocomposites and its array of applications: a review

Titania (TiO₂) has been the focus of attention of researchers since the first demonstration of its capability to generate the photocatalytic splitting of water into hydrogen and oxygen. However, there seems to be a recent surge in the research activity, involving modified TiO₂ nanoparticles (NP), which are considered to be more effective due to different physicochemical properties in comparison to unmodified fine particle analogs. Several strategies have been employed to modify TiO₂ to reduce recombination rates of photogenerated charge carriers to enhance the optimal functioning of TiO₂. Doping with cations and anions and coupling it with another semiconductor are the most well-known modification methods used. Titania nanocomposites are known to have a plethora of applications. Photoexcitation of these particles are seen to be extraordinarily effective in eliciting microbial death which makes it an attractive candidate for the manufacturing of antimicrobial coatings. On the other hand, TiO₂ induces the oxidation of various organic refractory compounds like tetracycline, sulfamethazine, and bisphenol. The photo-electrocatalytic oxidation technique which amalgamates the principle of photocatalysis and electrolysis serves as a newer, unswerving, and cost effective water treatment process. In the biomedical arena, use is now acknowledged for the photodynamic therapy of cancer, cell imaging, biological sensors, drug delivery system, and as endonucleases. In the commercial front, it is utilized in creams owing to its small particle size, which facilitates absorption through skin. It is also employed as ultraviolet blocking agents in sunscreen and commonly encountered as a brilliant white pigment in paint due to its brightness, high refractive index and resistance to discoloration. Its use in solar cells has also been reported. This review aims to encompass the new progress of modified TiO2 nanocomposites for efficient applications, emphasizing the future trends of TiO2 in arenas like healthcare, environment, biomedical, food, personal care, and pharmacy and also highlights the commercial implications of this promising nanomaterial.     

The morality behind sustainability

The concepts of sustainable agriculture, organic agriculture, regenerative agriculture, and alternative agriculture are receiving increasing attention in the academic and popular literature on present trends and future directions of agriculture. Whatever the reasons for this interest, there nevertheless remain differences of opinion concerning what counts as a sustainable agriculture. One of the reasons for these differences is that the moral underpinnings of a policy of sustainability are not clear. By understanding the moral obligatoriness of sustainability, we can come to understand precisely what must be sustained, and by implication, how. This article discusses the arguments that can be advanced for sustaining anything and initially concludes that our obligations to future generations entail sustaining more than just sufficient food production or an adequate resource base. Indeed, a tradition of care and community must underlie whatever agricultural and resource strategies we are to develop under the rubric of sustainability. A consideration of the larger social and environmental system in which agriculture operates and the constraints this system places on agriculture forces us to recognize that sustainability has to do with larger institutional issues, including our ability to incorporate our common morality democratically into our institutions, practices, and technologies.