金华城区小型兽类种类组成

1997年1月至1999年12月，选择金华城区的居民区、宾馆、粮库和工厂等4种生境5个调查点以夹夜法对常规灭鼠中小型兽类的种类组成进行了分析和研究。结果表明：金华城区共有臭QuQin(Suncus murinus)、褐家鼠（Rattus norvegicus)、黄胸鼠（Rattus flavipectus)、小家鼠（Mus musculus)和黑线姬鼠（Apodemus agrarius)等5种小型兽类；种类组成呈现以褐家鼠为主，臭QuQin和黑线姬鼠为次，黄胸鼠和小家鼠较少的格局；种类组成在不同的生境和各月份中都有所不同。     

Discovery of an electrical post-pulse in the surroundings of a high voltage spark discharge

In the vicinity of a high voltage spark, an electrical pulse of negative polarity was observed. The pulse's behavior with respect to spark cathode composition, gas flow, spatial distribution, and related parameters was characterized. Suggestions as to the origin of the pulse are made. Attempts at observing laser-enhanced ionization in the post discharge time period are described.     

城市综合经济实力的主成份分析

欧俊豪等．城市综合经济实力的主成份分析．对全国１９个大城市的１９９３、１９９５二年数据进行了主成份分析,提出用第一主成份作为城市综合经济实力的度量,给出了这些城市综合经济实力的排序     

Anomalous ratios of radioisotopes in PM10 as tracer of global fallout impact in the centre of Mexico

The monitoring and evaluation of radioactive content in samples of PM₁₀ aerosols have been investigated. The specific radioactivity concentrations (SRC) of ²³⁴U, ²³⁵U, ²³⁸U and ²³²Th were determined using inductively coupled plasma-sector field mass spectrometry in 13 samples collected in Mexico City and 8 samples collected in Cuernavaca in the centre of Mexico. The SRC of the radioisotopes analysed in PM₁₀ were larger than those reported in PM_2.5. The enrichment factor was greater than 5, indicating anthropogenic influences in both sites. The activity ratios of these isotopes in the samples were determined. The ²³⁵U/²³⁸U ratio showed variations with respect to the natural value, while the ²³⁴U/²³⁸U and ²³²Th/²³⁸U ratios did not show any secular equilibrium in all sites, corroborating that the increase of uranium is not influenced by natural sources. The annual dose results obtained have no impact on health.     

北京故宫养心殿燕喜堂及西围房建筑彩画的分析研究——一种检测颜料和胶结物的集成检测方法

北京故宫是现存规模最大、保存最完整的木结构古建筑群。2015年底,故宫养心殿启动研究性保护修缮工程,燕喜堂是养心殿的后殿西耳房,是此次维修的重点对象之一。彩画是古建筑的重要组成部分,不仅具有美化装饰的作用,更有对木材的防腐保护功能。为了能更好地辅助燕喜堂及西围房建筑彩画的保护与修复,需要对彩画原始材料以及工艺进行检测研究。使用一套集成检测方法：包括样品横截面分析、扫描电子显微镜背散射及能谱技术、拉曼光谱技术、荧光染色法、酶联免疫法、免疫荧光法以及热裂解气相色谱法,分析了故宫养心殿燕喜堂及西围房建筑彩画样品的颜料、沥粉、胶结材料的成分,以及结构关系。结果表明燕喜堂西围房使用的颜料有朱砂、铁红、群青、石青、石绿以及副氯铜矿型铜绿;沥粉的无机组成为石英、滑石、白垩或白云石。胶结材料检测结果发现彩画地仗层中普遍掺加了桐油,颜料层中掺加了动物胶。梁上彩画除了表面图案,地仗层底部还有一层朱砂颜料,同时地仗层内部也不规则地发现朱砂颜料。此外,表层红色颜料通常由两层颜料组成,内层的显色成分是铁红和朱砂,颜料颗粒直径1 μm左右,外层颜料由朱砂组成,颜料颗粒大小不一,直径1～30 μm范围内。上述检测结果不仅可以部分看出燕喜堂及西围房建筑彩画的工艺特征,也表明该集成检测方法可行、所需样品量少,是一种经济实用的彩画文物检测方法。     

A cellular automata model for urban traffic with multiple roundabouts

Urban transportation with multiple roundabouts is facing significant challenges such as traffic congestion, gridlock and traffic accidents. In order to understand these behaviors, we propose a two-dimensional cellular automata (CA) model, where all streets are two-way, with one lane in each direction. To allow the turning movement, a roundabout is designed for each intersection where four roads meet. The distance between each pair of roundabouts is configured with the parameter K while the turning behavior of drivers is modeled by a parameter γ. To study the impact of these different parameters on the urban traffic, several traffic metrics are considered such as traffic flow, average velocity, accident probability and waiting time at the entrance of roundabout. Our simulation results show that the urban traffic is in free flow state when the vehicle’s density is low enough. However, when the density exceeds a critical density ρ_c, the urban traffic will be in gridlock state whenever γ is nonzero. In the case where $\gamma =0,$ the urban traffic presents a phase transition between free flow and congested state. Furthermore, detailed analysis of the traffic metrics shows that the model parameters (γ, K) have a significant effects on urban traffic dynamics.     

Plasmon modes in 3-layer graphene structures: Inhomogeneity effects

We calculate the plasmon frequency and damping rate in a 3-layer graphene system made of parallel monolayer and bilayer graphene sheets using the random-phase-approximation dielectric function and taking into account the inhomogeneity of the dielectric background of the system. Numerical results show that two out-of-phase acoustic and one in-phase optical plasmon modes can be found from the zeroes of dynamical dielectric function of the structure. Plasmon frequencies and damping rate of plasma oscillations depend significantly on the inhomogeneity of environment, so plasmon curves become more distinctive from each other in single-particle excitation region, compared to the case of homogeneous medium. Finally, Plasmon dispersion patterns depend remarkably on the number (but not order) of bilayer graphene sheet constructing to the system.     

Multivariate classification and modeling in surface water pollution estimation

The present study deals with the application of self-organizing maps (SOM) and multiway principal-components analysis to classify, model, and interpret a large monitoring data set for surface water quality. The chemometric methods applied made it possible to reveal specific quality patterns of the chemical and biological parameters used to monitor the water quality (relation between water temperature, turbidity, hardness, colibacteria), seasonal impacts during the long period of observation and the relative independence on the spatial location of the sampling sites (water supply sources for the City of Trieste). Figure The schematic procedure for surface water pollution estimation supported by neural network-based classification and multivariate factor analysis     

Heavy metals as toxicants in big cities

Heavy Metals (HMs) can exert detrimental effects on human health and on the environment. Their ecotoxicological properties are generally well known. As regards human toxicology, new aspects should be taken into consideration—gender and age dependence. The HMs chemical risk can be estimated and in this context, city demography data help to evaluate today's ecological situation (including HMs) and to predict the dynamics of future urbanization.As regards urban atmosphere, motor vehicles (Pb) and industry (V, Ni, Cr, Cd) exert the greatest influence; water, soil, vegetation also experience menace caused by HMs. Urban environments should be protected against contamination posed by HMs: the health status of big cities is dependent on adequate and safe supply of water. Vegetation plays a helpful role in reducing HM content in the atmosphere and the soil. Awareness of the inhabitants regarding the risks posed by HMs also counts as critical factor today. Ecoeducation at the beginning of the new century can be taken into consideration.     

邯郸市水资源承载力评价与预测研究

选取水资源评价指标体系,运用复合模糊评价模型,对201.2年邯郸市水资源承载力(WRCC)进行了评价,得出WRCC为0.4145,表明邯郸市处于可承载的中游水平.接着通过灰色预测方法对邯郸市2020年的主要相关指标进行预测,再次利用复合模糊评价模型对水资源承载力进行综合评价,得出WRCC为0.5495,表明邯郸市的水资源还处于可承载的范畴,而且比2012年的水资源承载能力有所提高,分析结果为邯郸市水资源的合理利用及可持续发展提供一定理论依据.