杭州西湖富营养化防治设施最佳运行方式探讨

通过分析西湖富营养化主要影响因素及其防治措施的时效性,探讨现有各种防治设施的最佳运行方式,以降低治理费用、提高治理效果。     

中石油企业可接受风险标准初步研究

本文根据可接受风险标准的确定方法和制定原则,提出了中石油企业可接受风险标准,包括员工个人可接受风险标准和员工社会可接受风险标准。     

Effects of synthesis methods on the performance of Pt + Rh/Ce0.6Zr0.4O2 three-way catalysts

The 0.7 wt% Pt + 0.3 wt% Rh/Ce0.6Zr0.4O2 catalysts were fabricated via different methods, including ultrasonic-assisted membrane reduction(UAMR) co-precipitation, UAMR separation precipitation, co-impregnation, and sequential impregnation. The catalysts were physico-chemically characterized by N2 adsorption, XRD, TEM, and H2-TPR techniques, and evaluated for three-way catalytic activities with simulated automobile exhaust. UAMR co-precipitation- and UAMR separation precipitationprepared catalysts exhibited a high surface area and metal dispersion, wide λ window and excellent conversion for NOx reduction under lean conditions. Both fresh and aged catalysts from UAMRprecipitation showed the high surface areas of ca. 60–67 m2/g and 18–22 m2/g, respectively, high metal dispersion of 41%–55%, and small active particle diameters of 2.1–2.7 nm. When these catalysts were aged, the catalysts prepared by the UAMR method exhibited a wider working window(Δλ = 0.284–0.287) than impregnated ones(Δλ = 0.065–0.115) as well as excellent three-way catalytic performance, and showed lower T50(169.C) and T90(195.C) for NO reduction than the aged catalysts from impregnation processes, which were at 265 and 309.C, respectively. This implied that the UAMR-separation precipitation has important potential for industrial applications to improve catalytic performance and thermal stability. The fresh and aged 0.7 wt% Pt + 0.3 wt% Rh/Ce0:6Zr0:4O2 catalysts prepared by the UAMR-separation precipitation method exhibited better catalytic performance than the corresponding catalysts prepared by conventional impregnation routes.     

海水淡化集成技术的相关研究

为了降低海水淡化的成本和能耗,对海水淡化的集成工艺进行相应研究。海水淡化集成技术主要分为两种形式:一是不同海水淡化工艺的集成,二是能源和海水淡化的集成。首先介绍了海水淡化工艺的相关集成技术,包括热法与热法集成、膜法与膜法集成、热法与膜法集成、预处理工艺与海水淡化的集成工艺;其次介绍了各种新能源与海水淡化耦合方式、代表工程及研究现状,最后对海水淡化集成技术的优化提出建议。     

Size distribution, directional source contributions and pollution status of PM from Chengdu, China during a long-term sampling campaign

Long-term and synchronous monitoring of PM₁₀ and PM_2.5 was conducted in Chengdu in China from 2007 to 2013. The levels, variations, compositions and size distributions were investigated. The sources were quantified by two-way and three-way receptor models (PMF2, ME2-2way and ME2-3way). Consistent results were found: the primary source categories contributed 63.4% (PMF2), 64.8% (ME2-2way) and 66.8% (ME2-3way) to PM₁₀, and contributed 60.9% (PMF2), 65.5% (ME2-2way) and 61.0% (ME2-3way) to PM_2.5. Secondary sources contributed 31.8% (PMF2), 32.9% (ME2-2way) and 31.7% (ME2-3way) to PM₁₀, and 35.0% (PMF2), 33.8% (ME2-2way) and 36.0% (ME2-3way) to PM_2.5. The size distribution of source categories was estimated better by the ME2-3way method. The three-way model can simultaneously consider chemical species, temporal variability and PM sizes, while a two-way model independently computes datasets of different sizes. A method called source directional apportionment (SDA) was employed to quantify the contributions from various directions for each source category. Crustal dust from east-north-east (ENE) contributed the highest to both PM₁₀ (12.7%) and PM_2.5 (9.7%) in Chengdu, followed by the crustal dust from south-east (SE) for PM₁₀ (9.8%) and secondary nitrate & secondary organic carbon from ENE for PM_2.5 (9.6%). Source contributions from different directions are associated with meteorological conditions, source locations and emission patterns during the sampling period. These findings and methods provide useful tools to better understand PM pollution status and to develop effective pollution control strategies.     

陕西农业主要病虫灾害演变及控制途径

本文论述了陕西农业主要病虫灾害的发生和演变过程。指出演变的总趋势是主要农作物病虫害趋向严重且种类不断增多。并以此提出了主要病虫害的控制途径。     

干旱区城市水资源的可持续利用--以包头市为例

分析、评述了包头市城市水资源开发、利用状况,揭示出开发、利用中存在的主要问题,并用供需平衡法预测了2005年、2010年规划年包头市城市水资源供需水平及水量余缺情况,提出了合理利用水资源的对策、措施.     

以科学的思维方式指导船舶安全工作

船舶安全工作是海上运输生产的重中之重,而人的因素是决定安全工作的关键.本文提出科学的思维方式是船舶安全工作之本,引入普遍联系的原则、永恒发展的原则和矛盾问题的精髓三原理来研究了如何运用辩证思维来增强船舶安全工作中的系统性、预见性和创造性.     

间歇曝气短程硝化控制新途径的初步试验研究

采用SBR,以间歇曝气的方式控制短程硝化,分别研究了在限制曝气量和不限制曝气量条件下,亚硝酸盐的积累情况.试验表明,间歇曝气可以作为短程硝化的控制条件,在一定条件下,亚硝化率可达到90%以上.限制曝气量时,在低DO情况下,采用间歇曝气控制短程硝化更为有效、经济.     

论建设生态文明

为更好地贯彻落实十六大和十六届三中全会精神,实现物质文明、政治文明、精神文明,全面建设小康社会奋斗目标,应积极提倡生态文明建设。