Sustainable Use of Coffee Husks For Reinforcing Polyethylene Composites

The utilization of the coffee husk fiber (CHF) from the coffee industry as a reinforcing filler in the preparation of a cost-effective thermoplastic based composite was explored in this study. The chemical composition and thermal properties of the CHF were investigated and compared with those of wood fiber (WF). CHF proved to be mainly composed of cellulose, hemicellulose and lignin, and exhibited similar thermal behavior to WF. High density polyethylene (HDPE) composites with CHF loadings of from 40 to 70% were prepared using melt processing and extrusion. The processing properties, mechanical behavior, water absorption and thermal performance of these composites were investigated. The effect of maleated polyethylene (MAPE) used as a coupling agent on the composite was explored. The experimental results showed that increasing the CHF loading in the HDPE matrix resulted in an increase in the modulus and thermal properties of the composites, but resulted in poor water resistance. The addition of a 4% MAPE significantly improved the interfacial behavior of the hydrophilic lignocellulosic fiber and the hydrophobic polymer matrix.     

宏观环境与攀枝花资源开发研究

攀枝花是我国＂资源聚宝盆和天然温室＂,国际市场和国内经济建设需要是攀枝花资源开发的重要前提。攀枝花经过２０多年建设,已经在资源开发方面打下了良好的基础。为了更好地开发攀枝花的资源,使之为国民经济建设发挥更重要的作用,促进长江产业带建设,需积极、有效地开发攀枝花的资源。文中列举了有关开发资源的重大项目和改善投资环境、人才环境所必须的基础设施。     

Comparative analysis of small mammal communities in Chisinau and Yaroslavl, two European cities located in different biomes

Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses.     

Community-Based Integrated Watershed Management

1 INTRODUCTIONIn the past, natural resources management initiatives havefocused on large but specific sector projects such as dams,reservoirs for water supply schemes, irrigation systems,crop production, at forestation, etc. Often these projectswere treated as technical and administrative issues ratherthan as a socio-economic and political one. However, thehigh social and environmental cost of such schemes haveled to a change of paradigm since the 1980s towards small-scale community projec…     

The evolution of Müllerian mimicry

It is now 130 years since Fritz Müller proposed an evolutionary explanation for the close similarity of co-existing unpalatable prey species, a phenomenon now known as Müllerian mimicry. Müller's hypothesis was that unpalatable species evolve a similar appearance to reduce the mortality involved in training predators to avoid them, and he backed up his arguments with a mathematical model in which predators attack a fixed number (n) of each distinct unpalatable type in a given season before avoiding them. Here, I review what has since been discovered about Müllerian mimicry and consider in particular its relationship to other forms of mimicry. Müller's specific model of associative learning involving a "fixed n" in a given season has not been supported, and several experiments now suggest that two distinct unpalatable prey types may be just as easy to learn to avoid as one. Nevertheless, Müller's general insight that novel unpalatable forms have higher mortality than common unpalatable forms as a result of predation has been well supported by field experiments. From its inception, there has been a heated debate over the nature of the relationship between Müllerian co-mimics that differ in their level of defence. There is now a growing awareness that this relationship can be mediated by many factors, including synergistic effects between co-mimics that differ in their mode of defence, rates of generalisation among warning signals and concomitant changes in prey density as mimicry evolves. I highlight areas for future enquiry, including the possibility of Müllerian mimicry systems based on profitability rather than unprofitability and the co-evolution of defence.     

公路路网建设项目声环境影响评价研究

以甘肃省某市新区基础设施建设中的路网建设为例,根据公路路网的交通参数、道路地形地貌条件、路面设施等,利用导则推荐模式预测路网噪声贡献值。该新区路网中道路距离多在500m以上,不论道路平行还是相交,噪声影响以主干道为主,以次干道为辅,相互影响;根据路网噪声环境影响的特点,提出切实可行的声环境影响减缓措施。     

Ethanol mediated As(III) adsorption onto Zn-loaded pinecone biochar: Experimental investigation, modeling, and optimization using hybrid artificial neural network-genetic algorithm approach

Organic matters (OMs) and their oxidization products often influence the fate and transport of heavy metals in the subsurface aqueous systems through interaction with the mineral surfaces. This study investigates the ethanol (EtOH)-mediated As(III) adsorption onto Zn-loaded pinecone (PC) biochar through batch experiments conducted under Box–Behnken design. The effect of EtOH on As(III) adsorption mechanism was quantitatively elucidated by fitting the experimental data using artificial neural network and quadratic modeling approaches. The quadratic model could describe the limiting nature of EtOH and pH on As(III) adsorption, whereas neural network revealed the stronger influence of EtOH (64.5%) followed by pH (20.75%) and As(III) concentration (14.75%) on the adsorption phenomena. Besides, the interaction among process variables indicated that EtOH enhances As(III) adsorption over a pH range of 2 to 7, possibly due to facilitation of ligand–metal(Zn) binding complexation mechanism. Eventually, hybrid response surface model–genetic algorithm (RSM–GA) approach predicted a better optimal solution than RSM, i.e., the adsorptive removal of As(III) (10.47 μg/g) is facilitated at 30.22 mg C/L of EtOH with initial As(III) concentration of 196.77 μg/L at pH 5.8. The implication of this investigation might help in understanding the application of biochar for removal of various As(III) species in the presence of OM.     

偏远高山湿地土壤中PAHs污染特征:以神农架大九湖为例

于2012年4月沿大九湖湿地平均分布10个采样点,各采集0~10、10~20以及20~30 cm浅层土壤,采用GC-MS对大九湖湿地浅层土壤中USEPA 16种优控多环芳烃（PAHs）进行分析,对其分布、组成、来源进行了详细的讨论,并对高山湿地PAHs污染标志物进行了浅析.结果表明,研究区0~10、10~20、20~30cm浅层土壤中∑₁₆PAHs含量分别为48.55~984.73、14.36~806.47、12.84~1191.53 ng·g^-1,均值分别为302.94、142.98、208.68 ng·g^-1;7种致癌单体多环芳烃含量范围分别为21.20~844.29、2.96~592.06、0.66~964.70 ng·g^-1,均值分别为197.25、93.16、147.16 ng·g^-1,分别占总PAHs的65.12%、65.13%、69.08%;泥炭区PAHs含量明显高于非泥炭区,且已达到重度污染程度;PAHs组成以4、5、6环为主;结合IcdP/（IcdP+BghiP）及Pyr/BaP比值分析,推测大九湖湿地浅层土壤中PAHs主要来源于化石燃料及木材的燃烧,近年来旅游车辆的进入对PAHs的贡献较大;对浅层土壤中各单体PAH与PAHs总含量进行回归分析表明、苯并（b）荧蒽、茚（1,2,3cd）并芘、苯并（a）蒽作为泥炭地PAHs标志性化合物,用来评价PAHs的污染程度.     

Source identification, contamination status and health risk assessment of heavy metals from road dusts in Dhaka, Bangladesh

In this study, concentrations of Cr, Mn, Ni, Cu, Zn, Cd and Pb were determined in road dusts collected from different locations in Dhaka to assess source, contamination status and health risk. Energy-dispersive X-ray fluorescence spectroscopy and energy-dispersive X-ray spectroscopy were used to determine Cr, Mn, Ni, Cu, Zn, Cd and Pb and their mean concentrations were 162.27 ± 29.46, 721.18 ± 180.14, 35.65 ± 12.55, 104.56 ± 128.33, 515.32 ± 321.90, BDL, and 342.82 ± 591.20 mg/kg, respectively. Among the heavy metals, highest concentrations of Cu, Zn and Pb were found at urban sites-7 (municipal waste dumping) and 8 (medical waste incineration). Highest concentration of Cr followed by Cu and Zn was found at site-5 (Tejgaon, urban). Principal component analysis revealed that anthropogenic activities are the potential sources for Cr, Ni, Cu, Zn and Pb while earth crust for Mn. Pollution index and pollution load index results suggested that all the sites were contaminated and/or degraded by Cr, Cu, Zn and Pb except sites-9 (urban), 10 (sub-urban), 11 (rural) while sites-7 and 8 (urban) were extremely degraded. For noncarcinogenic health risk, hazard quotient values for dermal were higher compared to that of inhalation/ingestion. Though hazard index values were less than 1 at all the sites, these were at least one order of magnitude higher for children group than that of adult group, thus the children group may face more noncarcinogenic health risk at sites-7 and 8. Values of incremental lifetime cancer risk were from 10⁻⁹ to 10⁻¹¹ showed no carcinogenic health risk by road dusts contaminated with the heavy metals.     

Extraction of DNA from amniotic fluid cells for the early prenatal diagnosis of genetic disease

Ten-ml samples of amniotic fluid were taken from pregnancies being terminated at 8–14 weeks' gestation. DNA was extracted from the amniotic cells by sequential centrifugation and analysed using the polymerase chain reaction (PCR). Fifteen samples were analysed for evidence of maternal contamination using Mfd5 oligo-nucleotide primers for repeat polymorphisms. Ten amniotic fluid samples were tested for the Delta-F₅₀₈ deletion characteristic of cystic fibrosis to demonstrate a diagnostic application for the technique. In each case, DNA extracted from fetal tissue from the same pregnancy was included in the controls. In 14 of the 15 cases tested with the Mfd5 primers, both the amniotic fluid DNA and the fetal DNA showed no evidence of contaminating DNA. In one case, neither the amniotic fluid cells nor the fetal cells yielded results. In nine of the ten cases tested with the Delta-F₅₀₈ primers, the amniotic fluid cell DNA provided accurate information about the genetic status of the fetus; in the tenth, the fetal DNA failed to amplify. The results indicate that adequate DNA can be extracted from amniotic fluid from 8 weeks' gestation onward and these samples are suitable for prenatal diagnosis using PCR.