A Geochemical and Geophysical Characterization of Sulfide Mine Ponds at the Iberian Pyrite Belt (Spain)

This work presents the results of a geochemical and geophysical characterization of the Monte Romero and La Naya mine ponds, belonging to the Cueva de la Mora and Riotinto mine districts, respectively, based on mineralogical, geochemical and geophysical techniques. In order to obtain a representative environmental characterization, two deposits showing different mineralogies, physico-chemical parameters, chemical compositions of tailings and pond conditions were selected. Monte Romero mine tailings showed an upper level mainly composed of silicates and a deeper level mainly composed of sulfides and barite. The toxic metal content was different in both levels but high enough to exceed the regional legal concentration limits for agricultural soils. An electrical resistivity tomography survey revealed a homogeneous upper unit (3?m thickness), which displayed low resistivity values, corresponding to water-saturated silt and clay materials with an abundance of sulfides which was interpreted as the pond infilling. The La Naya mine pond presented a homogeneous mineralogical composition made up of quartz as the main mineral and chlorite-smectite and jarosite as accessory phases. The absence of sulfide phases and the low contents of metal elements are directly related to the reworking processes of the sludge dumped in this pond. The geophysical survey revealed that the pond infilling did not have a constant thickness, but ranged between 15 and 20?m. An inner groundwater flow in the infilling was recognized. The low resistivity values allowed the presence of acid waters and related subsurface flows to be identified in both mine ponds, but no acid water drainage occurred across their vessels. When compared to the Aznalc??llar tailings spill, the La Naya pond is large enough to release a similar amount of sludge, but of a very low metal content. The Monte Romero sludge displays a similar, potentially toxic metal content to the Aznalc??llar sludge, but its size is significantly smaller.     

Scales in single root water uptake models: a review,analysis and synthesis

Scales in transport of water to roots are compared with the length and volume scales by using the concepts associated with the representative elementary volume (REV). The possibility of a mismatch between model scale and system scale when using a Darcy‐Buckingham‐based model to describe soil water transport to a single root is evaluated. In the absence of a mismatch, the replication requirements for evaluating the Darcy‐Buckingham‐based model near a single root are discussed by using a synthesis of the elementary scales involved, including those for soil, plant and roots, and of the measurement device. By using REV scales from lattice‐Boltzmann simulations, the effective half‐root mean distance and the available measurement techniques, the evaluation of Darcy‐based single root uptake models is possible in roughly 50% of the combinations of soil‐ and root‐system properties. On the basis of an assessment of the scale characterizing natural soil variability, the number of replicates required to assess the average root water uptake profile near a single root is large, and either requires miniaturization of the measurement methods for the hydraulic transport characteristics, or very homogeneous (artificial) growing media with little variability. Variability of water uptake per unit root length will increase the number of samples required.     

Thermal degradation of anthocyanins from purple potato (cv. Purple Majesty) and impact on antioxidant capacity

Degradation parameters of purified anthocyanins from purple-fleshed potato (cv. Purple Majesty) heated at high temperatures (100-150 °C) were determined. Purified anthocyanins, prepared by removing salts, sugars, and colorless nonanthocyanin phenolics from the crude extract, were monitored and quantified using HPLC and spectrophotometry for heat-induced degradation products. Separation of colorless phenolics from the anthocyanins was confirmed using HPLC at two wavelengths, 280 and 520 nm. The degradation kinetics of purified anthocyanins followed a first-order reaction with reaction rate constants (k values) of 0.0262-0.2855 min(-1), an activation energy of 72.89 kJ/mol, thermal death times (D values) of 8.06-8789 min, and a z value of 47.84 °C over the temperature range of 100-150 °C. The enthalpy and entropy of activation were 59.97 kJ/mol and -116.46 J/mol·K, respectively. The antioxidant capacity in the purified anthocyanins, measured by DPPH and ABTS assays, was increased after the thermal treatment, indicating antioxidant activities of degradation products in the samples.     

上海青浦地区环境资源与可持续发展问题

本文对上海市青浦区实施可持续发展的环境资源条件和存在的问题作了探索,并就青浦区实现可持续发展战略提出若干对策措施.     

Genome-wide association for milk production and lactation curve parameters in Holstein dairy cows

The aim of this study was to identify genomic regions associated with 305-day milk yield and lactation curve parameters on primiparous (n = 9,910) and multiparous (n = 11,158) Holstein cows. The SNP solutions were estimated using a weighted single-step genomic BLUP approach and imputed high-density panel (777k) genotypes. The proportion of genetic variance explained by windows of 50 consecutive SNP (with an average of 165 Kb) was calculated, and regions that accounted for more than 0.50% of the variance were used to search for candidate genes. Estimated heritabilities were 0.37, 0.34, 0.17, 0.12, 0.30 and 0.19, respectively, for 305-day milk yield, peak yield, peak time, ramp, scale and decay for primiparous cows. Genetic correlations of 305-day milk yield with peak yield, peak time, ramp, scale and decay in primiparous cows were 0.99, 0.63, 0.20, 0.97 and −0.52, respectively. The results identified three windows on BTA14 associated with 305-day milk yield and the parameters of lactation curve in primi- and multiparous cows. Previously proposed candidate genes for milk yield supported by this work include GRINA, CYHR1, FOXH1, TONSL, PPP1R16A, ARHGAP39, MAF1, OPLAH and MROH1, whereas newly identified candidate genes are MIR2308, ZNF7, ZNF34, SLURP1, MAFA and KIFC2 (BTA14). The protein lipidation biological process term, which plays a key role in controlling protein localization and function, was identified as the most important term enriched by the identified genes.     

"十五"期间重庆雾水化学特征研究

“十五”期间重庆市区雾水呈酸性,近郊区雾水呈弱酸性,远郊区基本未酸化;由市区向外,雾水的电导率逐步降低,阴离子浓度逐步降低,钙离子、铵根离子和钾离子浓度也逐步降低,但钠离子和镁离子则有所不同;重庆雾水的酸化类型以硫酸型为主,其次是盐酸型和硝酸型.雾水的碱化类型在市区和远郊区以钙—铵型为主,在近郊区以钙型为主.雾水中离子浓度比雨水高出数倍.     

新型蔬菜洋蓟的引种研究

对从美国、西班牙引进的二个洋蓟品种绿球GreenGlobeArtichoke和帝王之星ImperiaLArti-choke进行引种栽培试验和品质性状比较分析。结果表明,引进的两个洋蓟品种在云南中部地区有很好的适应性,冬季露地能越冬,生长势强,能实现低成本高品质的产业化运作。其中,绿球GreenGlobeArtichoke表现出较高的生产潜力和优良品质,最具推广栽培前景。     

元谋干热河谷区热带优良牧草柱花草引种试验*

 通过对60个柱花草种质材料引种试验, 参照层次分析法综合分析了60个柱花草长势、抗旱、抗寒、产量特性及品质特性。结果表明: CIAT1044(2) 柱花草、TPRC90105柱花草、CIAT1363(2)柱花草、TPRC90005柱花草、TPRC90037(2) 柱花草、有毛L7柱花草、GC1578柱花草、TPRC L8柱花草、L1(90096)柱花草、R93柱花草、GC1524EMBRAPA柱花草和热研2号柱花草居前10位,抗寒及抗旱性强,产量高,长势好,品质优良,可在云南干热河谷区推广应用。     

RLD调速器特点及其故障分析

RLD调速器是目前比较先进的一种调速器,它的主要特点是怠速、高速、及满负荷的油量校正都是单独调整的.以便更好地匹配各种不同的发动机.其调速范围广,故主要作为车用.但由于其结构复杂,许多人都搞不清楚它的工作原理,因而给使用、修理和调试都带来许多困难.本文从结构入手,详细分析了它的工作原理和结构特点,以及常见故障的排除,以期给相关的研究和工作提供一些帮助.     

完善高等学校物资设备采购工作的思考

随着高等学校的发展，其物资设备的采购量越来越大，如何进一步规范高校的采购行为，以适应市场经济的要求，及与政府采购工作相衔接，是高校发展中需要认真解决的问题。本文提出了由政府主管部门加强对高校采购工作的规范和指导，高校自身完善制度、规范行为、加强基础工作、强化监察审计监督等规范采购行为、提高采购资金的使用效益的对策思路。