基于模拟植物生长算法的快线公共车辆优化调度研究

公共车辆的运营优化调度能够很好的减少城市交通拥堵,缓解交通压力,保证多方面的利益。对乘客高峰期快线公共车辆的调度进行了研究。首先运用了三元组α/β/γ方法对问题进行了描述,将乘客高峰期快线车辆的调度描述为一类以最小化制造期和平均等待时间为目标,具有先入先出原则和机器适用限制的流水车间动态调度问题。并在此基础上建立了相应的数学模型;接着,运用模拟植物生长算法进行了算法设计;最后,用实际数据进行了数值仿真,结果证明该研究具有较高的理论及现实价值。     

Relationships Between Copper Species and Forms,Hydrographic and Biomass Parameters in the Taiwan Erhjin Chi Coastal Area

The first incident of green oysters (Crassostrea gigas) was reported in Taiwan in the Charting coastal area in January, 1986 and mortality was reported three months later. the cause of the greened oysters was identified as copper pollution. the copper content of the green oysters was extremely high - 2100 ppm, 2225 ppm, and 4400 ppm dry weight, in January, 1986, February 1987, and January 1989, respectively. in this paper we summarize the seasonal and regional distributions of copper species (complexed by inorganic and organic ligands, labile and non-labile, polar and non-polar) and forms (dissolved and particulate) and the hydrographic and biomass parameters (mainly particulate organic carbon, chloropyll -α, adenosine triphosphate and primary production) in sea water in the Erhjin Chi coastal area. in general, high concentrations of particulate material (0.24 to 724 ppb) and non-labile organic copper (0.03 to 21.5 ppb) were observed. Low values of polar organic copper (<0.02 to 16.5 ppb) indicated that non-polar organic complexes (0.3 to 20.4 ppb) from man-made organic pollutants were the major complexes in the area studied. On the basis of this data, the cause of greening and mortality in oysters is evaluated in relation to the bioavailable copper (sum of particulate and labile copper) and copper assimilative capacity (detoxicant). Finally, the correlations between the species and forms of copper, hydrographic and biomass parameters are also discussed.     

Assessment of forest vegetation and conservation priorities of communities in part of Nanda Devi Biosphere Reserve,West Himalaya. Part I

In most protected areas of the Indian Himalayan region site/habitat characteristics, community diversity and distribution pattern, vegetation composition (richness of native and endemic species), structural patterns, economic importance of forest communities and community priorities have rarely been studied. Therefore, the present study has focused on these in the buffer zone of Nanda Devi Biosphere Reserve. Seventy-six woody species (trees: 24; shrubs: 52) and 13 forest communities have been recorded between 2300–3800 m asl. Tree density ranged from 533–1220 ind ha-¹, tree basal area from 14.68-80.28 m²ha-¹ and shrub density from 1490–6695 ind ha-¹. Mean density of trees was significantly lower in temperate forests in comparison to subalpine forests. Richness of trees ranged from 3–18 and shrubs from 5–29. Species diversity (H') of trees ranged from 0.45-2.08 and shrubs from 0.90-3.14. In the temperate zone, species richness and altitude had significant positive correlations whereas in the subalpine zone the two variables were negatively correlated. The native species were high in the area (> 65% species) and in communities (> 70% species), and was highest for the Picea smithiana-Pinus wallichiana mixed community, whereas the maximum numbers of natives and endemic species were recorded in the Pinus wallichiana community. The density and richness of non-natives were found to be significantly lower in comparison to the natives. Economic importance and conservation value of the communities were assessed and communities prioritized. Monitoring of the identified habitats, species, populations and communities, and development of appropriate strategies for their conservation and management are suggested.     

Managing a protected marine area for the conservation of critically endangered vaquita (Phocoena sinus Norris, 1958) in the Upper Gulf of California

We analysed fisheries trends in the northern region of the Gulf of California, within the Biosphere Reserve of the Upper Gulf of California and Colorado Delta River and the Vaquita Refuge Area, and suggest measures to protect the vaquita, Phocoena sinus. We compiled and analysed catch reports of artisanal fishermen in the three fishing communities of the Upper Gulf of California (San Felipe in the State of Baja California, and Golfo de Santa Clara and Puerto Peñasco in the State of Sonora) from 1995 to 2007. This information was categorised with respect to geographic information systems, and all fishing sites within two marine protected areas in the region were identified. In addition, from a survey based on direct interviews with artisanal fishermen in each of the three ports, we identified that 23% of fishermen will continue fishing despite on-going fishing buy-out programmes in the region. We suggest several specific courses of action to decrease the fishing impact on this critically endangered cetacean. However, given the critical situation of this critically endangered species, it is very uncertain whether enforcing a no-take zone within the biosphere reserve and the Vaquita Refuge Area, or even a wider fishing moratorium, will be enough to save this endangered species from extinction.     

红树植物凋落叶分解对土壤可溶性有机质的影响

研究红树林湿地土壤可溶性有机质（DOM）的来源、性质及其归宿对于揭示 DOM 在红树林湿地生物地球化学循环中的作用具有重要意义。采集了木榄（Bruguiera gymnoihiza）、秋茄（Kandelia candel）和桐花树（Aegiceras corniculatum）3种红树植物的新近落叶进行室内48 d分解实验,探讨了凋落叶分解过程对土壤可溶性有机碳（DOC）和可溶性总氮（TDN）含量、C/N比（DOC/TDN）及紫外-可见（UV-Vis）光谱特征（A280、A240/A420和A250/A365比值）的影响。在48 d分解期间,3种红树植物凋落叶的输入均明显增加了土壤DOC的含量,其变化在分解第6 d最为显著,各凋落叶添加组比对照组平均增加了149%（秋茄）~196%（桐花树）,随后各凋落叶添加组土壤DOC含量呈下降趋势。与土壤DOC的变化不同,凋落叶输入后土壤TDN的变化与对照组的差异不明显,但木榄和桐花树添加组的C/N比在分解初期（第6天）显著高于对照组（P<0.05）。凋落叶的输入亦在不同程度上增大了土壤DOM的A280值,降低了DOM的A240/A420和A250/A365比值。与土壤DOC的变化相似,凋落叶输入使DOM的UV-Vis光谱特征在分解初期（第6天）的变化最明显,其中桐花树凋落叶的影响最大,秋茄凋落叶的影响最小。结果表明：凋落叶输入使培养初期土壤DOM的含量和性质发生明显改变,DOM中大分子及芳香类组分增多、团聚化程度增加,DOM 的生物可降解性变小。然而,随着分解的进行,不同凋落叶处理组之间土壤DOM的变化差异性逐渐缩小,并在分解后期与对照组趋近。     

活性氧参与多壁碳纳米管诱导的RAW264.7细胞毒性

碳纳米管以其独特的结构和性能,在生物医药和电子等领域广泛应用,而其生态安全性也成为科学界关注的焦点。为探究多壁碳纳米管(MWCNTs)诱导的细胞毒性机制,将小鼠肺泡巨噬细胞(RAW264.7)暴露于6个浓度梯度(0、25、50、100、150和200μg.mL-1)的MWCNTs中,应用噻唑蓝(MTT)法测定细胞存活率,用2’,7’-二氯荧光素二乙酸(DCFH-DA)荧光染色法测定细胞内活性氧的生产量,用流式细胞方法测定MWCNTs对细胞周期的影响。同时使用抗氧化剂氮乙酰半胱氨酸(NAC)验证MWCNTs诱导的细胞氧化损伤的作用机理。结果显示,MWCNTs对RAW264.7的细胞毒性呈剂量依赖性。暴露于不同浓度的MWCNTs(25、50、100、150和200μg.mL-1)下24h后,细胞活力分别为对照的74%、62%、59%、51%和45%。MWCNTs对RAW264.7的周期阻滞作用主要发生在G0/G1期。200μg.mL-1的MWCNTs处理3h后活性氧较对照组上升6.6倍。NAC对MWCNTs细胞毒作用有明显的抑制作用,且NAC能减弱MWCNTs对RAW264.7的细胞周期阻滞作用。研究表明,活性氧能够介导MWCNTs对小鼠巨噬细胞RAW264.7的损伤,并且MWCNTS通过细胞周期G0/G1期的阻滞,诱导细胞凋亡。     

城市污水处理厂微生物气溶胶污染和粒径分布特征

城市污水处理厂微生物气溶胶的污染与控制逐渐成为人们关注的热点问题。为明确城市污水处理厂微生物气溶胶浓度和粒径分布特征,选择鄂尔多斯市某城市污水处理厂的格栅间、配水池、氧化沟、二沉池、污泥脱水间和厂区门口6个功能区为对象,对各功能区产生的异养细菌、真菌和放线菌气溶胶浓度分布、污染特性和微生物粒子粒径分布特性进行研究。结果表明,该污水处理厂不同功能区内异养细菌、真菌和放线菌的浓度分布存在显著性差异,其中二沉池和污泥脱水间产生的异养细菌和放线菌浓度均较高,真菌浓度较高的区域为厂门口和二沉池;根据相关微生物气溶胶污染评价标准,污泥脱水间逸散的异养细菌浓度均达到污染级,二沉池、氧化沟和厂门口逸散的异养细菌浓度达轻微污染级,格栅间和配水池未受污染,而真菌浓度在各个功能区均未受到污染;各功能区产生的异养细菌、真菌和放线菌粒子粒径分布无明显差异,异养细菌、真菌和放线菌粒子粒径分别集中在第1、4级,第3、4级和第1、2、3级,大体上均呈正态分布;各功能区均逸散出一定比例的可以直接吸入人体呼吸道的微生物粒子,可能对人体健康具有一定的潜在风险。研究结果可为城市污水处理厂运行过程中微生物气溶胶的污染控制提供科学依据。     

Emission factors of gaseous carbonaceous species from residential combustion of coal and crop residue briquettes

Experiments were performed to measure the emission factors (EFs) of gaseous carbonaceous species, such as CO₂, CO, CH₄, and non-methane volatile organic compounds (NMVOCs), from the combustion of five types of coal of varying organic maturity and two types of biomass briquettes under residential burning conditions. Samples were collected in stainless steel canisters and 2,4-dinitrophenylhydrazine (DNPH) cartridges and were analyzed by GC-FID/MS and HPLC, respectively. The EFs from crop residue briquette burning were generally higher than those from coals, with the exception of CO₂. The dominant NMVOC species identified in coal smoke were carbonyls (41.7%), followed by C2 unsaturated hydrocarbons (29.1%) and aromatics (12.1%), while C2 unsaturated hydrocarbons were the dominant species (68.9%) emitted from the combustion of crop residue briquettes, followed by aromatics (14.4%). A comparison of burning normal crop residues in stoves and the open field indicated that briquettes emitted a larger proportion of ethene and acetylene. Both combustion efficiency and coal organic maturity had a significant impact on NMVOC EFs from burning coal: NMVOC emissions increased with increasing coal organic maturity but decreased as the combustion efficiency improved. Emissions from the combustion of crop residue briquettes from stoves occurred mainly during the smoldering process, with low combustion efficiency. Therefore, an improved stove design to allow higher combustion efficiency would be beneficial for reducing emissions of carbonaceous air pollutants.     

我国重工业企业烟气脱硫技术及存在的问题

为使企业在"十二五"期间达到SO2减排指标,总结出几种目前应用普遍,技术成熟,投资、运行成本较低的脱硫工艺,包括烟气脱硫的基本原理、主要设备、技术难点及存在的问题。供企业新建,改建或扩建脱硫系统借鉴。     

Reduced effect of Tasmanian devil facial tumor disease at the disease front

Pathogen-driven declines in animal populations are increasingly regarded as a major conservation issue. The Tasmanian devil (Sarcophilus harrisii) is threatened with extinction by devil facial tumor disease, a unique transmissible cancer. The disease is transmitted through direct transfer of tumor cells, which is possible because the genetic diversity of Tasmanian devils is low, particularly in the major histocompatibility complex genes of the immune system. The far northwest of Tasmania now holds the last remaining disease-free wild devil populations. The recent discovery of unique major histocompatibility complex genotypes in the northwestern region of Tasmania has raised the possibility that some animals may be resilient to the disease. We examined the differences in the epidemiology and population effects of devil facial tumor disease at 3 well-studied affected sites in eastern Tasmania and 1 in western Tasmania (West Pencil Pine). In contrast to the 3 eastern sites, there has been no rapid increase in disease prevalence or evidence of population decline at West Pencil Pine. Moreover, this is the only onsite at which the population age structure has remained unaltered 4 years after the first detection of disease. The most plausible explanations for the substantial differences in population effects and epidemiology of the disease between eastern and western sites are geographic differences in genotypes or phenotypes of devils and functional differences between tumor strains in the 2 regions. We suggest that conservation efforts focus on identifying whether either or both these explanations are correct and then, if resistance alleles exist, to attempt to spread the resistant alleles into affected populations. Such assisted selection has rarely been attempted for the management of wildlife diseases, but it may be widely applicable.