自然保护区的现实问题与分区模式创新研究

传统封闭式和孤岛式的分区模式使得自然保护区的发展遭遇瓶颈。保护与开发之间的〉中突是目前自然保护区可持续发展的最大障碍。分区是自然保护区管理和经营的有效工具,以生态系统稳定性的弹性机制为理论依据,从栖息地适宜性、生态系统稳定性和生态系统敏感性3个维度构建自然保护区的有机分区方法。基于GIS技术的多标准判断法和生态演替分析法对自然保护区内的土地单元进行生态价值评估和分区,提出“核心区,缓;中区”2大区、“自然环境区／游赏区／生产经营区／科学实验区／管理服务区”5小区的划分方式。旨在通过生态价值的差异性对保护区内土地单元进行划分,从而解决自然保护区内不同利益者之间的矛盾,并且以马头山自然保护区为例对有机分区体系进行实证研究。     

新建综合医院住院部分期发展的空间模式及设计策略研究

面对综合医院功能、容量动态发展需求,住院部的分期发展是大势所趋.通过对大量案例的分析与研究,本文总结了综合医院住院部分期发展空间模式类型,并归纳出综合医院住院部分期发展的设计策略,倡导可持续发展、有机生长的医院规划理念,对现代医院设计实践具有参考价值.     

人居环境科学理论指导下城市传统公园的“有机更新”——以福州西湖公园改造更新为例

随着城市建设的发展,传统公园的改造面临着巨大的挑战,本文以西湖公园改造更新项目为例,分析目前传统公园改造存在的主要问题,运用人居环境科学理论以及"有机更新"的设计理念,提出了针对城市传统公园的改造原则和改造策略,在尽可能满足现代功能要求的同时,保护公园的传统文化与景观特色,打造具有艺术性、文化性与功能性的公园景观,体现可持续、科学的发展观。     

城市公园有机更新的方法研究——以福安富春公园更新为例

近几年来,随着城市建设进程的加快,一大批始建于20世纪的城市公园面临着改造更新。这些公园虽然大多衰老破败,已无法满足人们日常使用,但是这些公园又多处于旧城的核心区域,交通便捷,游憩设施和植物景观仍然有一定的使用价值,如何改造这些老旧的城市公园,使其焕发出新的生命力,是当前城市公园建设中的迫切问题。该文以福安富春城市公园更新为例,针对城市公园更新的特点,引入有机更新理论,指出城市公园更新必须遵循的整体性、阶段性、延续性、适宜性原则,同时应建立新建、改造、保护于一体的整体更新措施体系。     

Use of sequential ASE extraction to evaluate the bioavailability of DDT and its metabolites to wheat roots in soils with various organic carbon contents

An accelerated solvent extraction (ASE) procedure using water, n-hexane and a mixture of n-hexane and acetone as solvents in sequence was developed and tested to evaluate the bioavailability of DDT and its metabolites including p,p'-DDT, o,p'-DDT, p,p'-DDE, and p,p'-DDD (SigmaDDTs) to wheat uptake from soils characterized by varied organic carbon contents. Results indicated that the extractability of SigmaDDTs with water was enhanced considerably in the presence of water soluble organic carbon (WSOC), while the amount of SigmaDDTs extracted with n-hexane was negatively correlated to the content of water insoluble organic carbon (WIOC). The interaction between SigmaDDTs and WIOC also reduced the bioavailability of the pesticides to wheat roots during uptake. There was a good positive correlation between the amount of SigmaDDTs extracted by n-hexane and the amount of SigmaDDTs accumulated in wheat roots, suggesting some potential for the use of the n-hexane ASE-extracted fraction as an indicator of SigmaDDTs' bioavailability to plant uptake. As such, the three sequentially extracted fractions may be viewed as representing the mobile, bioavailable, and fixed pools of SigmaDDTs in the soil.     

Chemical compositions and source identification of PM₂.₅ aerosols for estimation of a diesel source surrogate

Exposure to traffic-related pollution during childhood has been associated with asthma exacerbation, and asthma incidence. The objective of the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) is to determine if the development of allergic and respiratory disease is associated with exposure to diesel engine exhaust particles. A detailed receptor model analyses was undertaken by applying positive matrix factorization (PMF) and UNMIX receptor models to two PM_2.5 data sets: one consisting of two carbon fractions and the other of eight temperature-resolved carbon fractions. Based on the source profiles resolved from the analyses, markers of traffic-related air pollution were estimated: the elemental carbon attributed to traffic (ECAT) and elemental carbon attributed to diesel vehicle emission (ECAD).Application of UNMIX to the two data sets generated four source factors: combustion related sulfate, traffic, metal processing and soil/crustal. The PMF application generated six source factors derived from analyzing two carbon fractions and seven factors from temperature-resolved eight carbon fractions. The source factors (with source contribution estimates by mass concentrations in parentheses) are: combustion sulfate (46.8%), vegetative burning (15.8%), secondary sulfate (12.9%), diesel vehicle emission (10.9%), metal processing (7.5%), gasoline vehicle emission (5.6%) and soil/crustal (0.7%). Diesel and gasoline vehicle emission sources were separated using eight temperature-resolved organic and elemental carbon fractions. Application of PMF to both datasets also differentiated the sulfate rich source from the vegetative burning source, which are combined in a single factor by UNMIX modeling. Calculated ECAT and ECAD values at different locations indicated that traffic source impacts depend on factors such as traffic volumes, meteorological parameters, and the mode of vehicle operation apart from the proximity of the sites to highways. The difference in ECAT and ECAD, however, was less than one standard deviation. Thus, a cost benefit consideration should be used when deciding on the benefits of an eight or two carbon approach.     

Impact of colloidal and soluble organic material on membrane performance in membrane bioreactors for municipal wastewater treatment

Two parallel membrane bioreactors (2 m3 each) were operated over a period of 2 years. Both pilots were optimised for nitrification, denitrification, and enhanced biological phosphorous elimination, treating identical municipal wastewater under comparable operating conditions. The only constructional difference between the pilots was the position of the denitrification zone (pre-denitrification in pilot 1 and post-denitrification in pilot 2). Despite identical modules and conditions, the two MBRs showed different permeabilities and fouling rates. The differences were not related to the denitrification scheme. In order to find an explanation for the different membrane performances, a one-year investigation was initiated and the membrane performance as well as the operating regime and characteristics of the activated sludge were closely studied. MLSS concentrations, solid retention time, loading rates, and filtration flux were found not to be responsible for the different performance of the submerged modules. These parameters were kept identical in the two pilot plants. Instead, the non-settable fraction of the sludges (soluble and colloidal material, i.e. polysaccharides, proteins and organic colloids) was found to impact fouling and to cause the difference in membrane performance between the two MBR. This fraction was analysed by spectrophotometric and size exclusion chromatography (SEC) methods. In a second step, the origin of these substances was investigated. The results point to microbiologically produced substances such as extracellular polymeric substances (EPS) or soluble microbial products (SMP).     

OLED微显示器的原子扫描策略

为了实现2K及以上超高清微型显示器的高效率高性能扫描,建立了微型显示器的原子扫描模型。对该模型采用的数学矩阵、基于分形延伸的植入运算进行研究,提出了原子扫描策略并推导了原子扫描序列。首先,对现有的PWM(脉冲宽度调制)扫描策略进行扫描性能分析。然后,在分析比较几种扫描策略性能的基础上,说明原子扫描是实现较优性能的最佳选择。实验结果表明:对于256级灰度,采用32位子空间,8位权值比为128∶64∶32∶16∶9∶4∶2∶1的原子扫描策略具有较好的线性度和较高的传输效率。在分辨率为1 600×1 600的原子扫描方案中,时钟频率为50MHz,帧频可达90Hz,线性度接近99.8%,传输效率高达100%,基本满足超高分辨率扫描系统中高帧频、较低时钟、高线性度的要求。     

不同SBR条件下焦化废水治理效果的研究

以泰安焦化厂经蒸氨除油预处理后的废水为研究对象，探讨用SBR法处理焦化废水的可行性及其运行特征。在实验室内考察了SBR操作模式和曝气时间等条件变化时焦化废水中有机物的降解及氨氮的去除效果。研究结果表明，采用SBR法在操作模式为瞬时进水-缺氧搅拌4h-曝气16h-停曝搅拌2．5h-沉淀排水1．5h条件下处理焦化废水，对有机物及氨氮的去除是有效的。     

Novel wide band-gap polymer utilizing fused hetero-aromatic unit for efficient polymer solar cells and field-effect transistors

Novel wide band-gap polymer of PBTFT containing dibenzosexithiophene-alt-bithiophene backbone was designed and synthesized via the Stille cross-coupling reaction. This polymer exhibited good thermal stability, well coplanar backbone and a broad absorption band from 350 nm to 610 nm with a wide optical band-gap of 2.02 eV. The polymer solar cells (PSCs) based on the PBTFT:PC₇₁BM active layer showed the power conversion efficiency of 3.0% with an open circuit voltage of 0.70 V, a short-circuit current of 7.94 mA cm⁻² and a fill factor of 53.98% under the illumination of AM.1.5, 100 mW cm⁻². Holes mobility up to 0.028 cm² V⁻¹ s⁻¹ with an on-off ratio of 1.0 × 10⁶ was obtained in the PBTFT-based organic field-effect transistors (OFETs). Our work indicates that the dibenzosexithiophene-alt-bithiophene based copolymer can be efficiently applied in PSCs and OFETs.