紫色甘薯花青素的提取工艺研究

对超声波辅助提取紫色甘薯花青素的工艺条件进行了研究,以花青素的提取率为评价指标,在单因素试验的基础上,利用响应面法对提取工艺条件进行优化。在分析了各因素的显著性和交互作用后,得出超声波辅助提取紫色甘薯花青素的最佳提取工艺:提取时间40 min,提取温度75℃,液料比10∶1,在此条件下,所得花青素提取率为1.70%。     

Ratio control strategy for solving system response lag of continuously variable transmission system

Generally, there’s a system response lag in the continuously variable transmission system, and this leads to a deviation of the engine work point from the optimal operation line of the minimum fuel consumption. To reduce the influence of system response lag, a new CVT ratio control strategy with the system response lag parameter during computing target ratio is proposed. Simulation results indicate that the proposed control strategy can overcome the effect of system response lag, so as to keep the engine work point on the optimal operation line effectively. A comparison of fuel consumption is made between the proposed control strategy and the traditional one by simulation, and results indicate that the proposed control strategy reduces the fuel consumption of the system by 2.85％.     

Transpirational response to water availability for winter wheat as affected by soil textures

Soil texture and evaporative demand have been reported to be the main factors which influence the transpirational response to soil water deficits. However, experimental evidences are not enough. The objective of this study was to investigate the transpirational response to soil water availability in soils of different textures under different evaporative demand levels. The three main soils of the Loess Plateau of China (loamy clay, clay loam and sandy loam) were selected and six constant soil water treatments were applied for winter wheat (Triticum aestivum L.) grown in pots. In order to reduce the influence of environmental conditions and plant factors, a normalized daily transpiration rate was used to develop the relationships with volumetric soil water content and soil water suction. Results showed that, under various levels of evaporative demand, a linear-plateau function with a critical value could be used to describe the dynamic change of the normalized transpiration rate with soil drying. Soil texture significantly influenced both the critical and the slope values of the linear-plateau equations, however, evaporative demand significantly affected the critical values of volumetric soil water content and soil suction for the loamy clay and clay loam only. Therefore, for saving water, different strategies are needed for these three soils.     

Comparison of drip and sprinkler irrigation strategies on sunflower seed and oil yield and quality under Mediterranean climatic conditions

This study compares the effects of different irrigation regimes on seed yield and oil yield quality and water productivity of sprinkler and drip irrigated sunflower (Helianthus annus L.) on silty-clay-loam soils in 2006 and 2007 in the Mediterranean region of Turkey. In sprinkler irrigation a line-source system was used in order to create gradually varying irrigation levels. Irrigation regimes consisted of full irrigation (I₁) and three deficit irrigation treatments (I₂, I₃ and I₄), and rain-fed treatment (I₅). In the drip system, irrigation regimes included full irrigation (FI-100), three deficit irrigation treatments (DI-25, DI-50, DI-75), partial root zone drying (PRD-50) and rain-fed treatment (RF). Irrigations were scheduled at weekly intervals both in sprinkler and drip irrigation, based on soil water depletion within a 0.90 m root zone in FI-100 and I₁ plots. Irrigation treatments influenced significantly (P < 0.01) sunflower seed and oil yields, and oil quality both with sprinkler and drip systems. Seed yields decreased with increasing water stress levels under drip and sprinkler irrigation in both experimental years. Seed yield response to irrigation varied considerably due to differences in soil water contents and spring rainfall distribution in the experimental years. Although PRD-50 received about 36% less irrigation water as compared to FI-100, sunflower yield was reduced by an average of 15%. PRD-50 produced greater seed and oil yields than DI-50 in the drip irrigation system. Yield reduction was mainly due to less number of seeds per head and lower seed mass. Soil water deficits significantly reduced crop evapotranspiration (ET), which mainly depends on irrigation amounts. Significant linear relationships (R² = 0.96) between ET and oil yield (Y) were obtained in each season. The seed yield response factors (ky_seed) were 1.24 and 0.86 for the sprinkler and 1.19 and 1.06 for the drip system in 2006 and 2007, respectively. The oil yield response factor (ky_oil) for sunflower was found to be 1.08 and 1.49 for both growing seasons for the sprinkler and 1.36 and 1.25 for the drip systems, respectively. Oil content decreased with decreasing irrigation amount. Consistently greater values of oil content were obtained from the full irrigation treatment plots. The saturated (palmitic and stearic acid) and unsaturated (oleic and linoleic acid) fatty acid contents were significantly affected by water stress. Water stress caused an increase in oleic acid with a decrease in linoleic acid contents. The palmitic and stearic acid concentrations decreased under drought conditions. Water productivity (WP) values were significantly affected by irrigation amounts and ranged from 0.40 to 0.71 kg m⁻³ in 2006, and from 0.69 to 0.91 kg m⁻³ in 2007. The PRD-50 treatment resulted in the greatest WP (1.0 kg m⁻³) and irrigation water productivity (IWP) (1.4 kg m⁻³) in both growing seasons. The results revealed that under water scarcity situation, PRD-50 in drip and I₂ in sprinkler system provide acceptable irrigation strategies to increase sunflower yield and quality.     

基于PLC的无糖组培微环境控制系统

为实现组培微环境CO2 增施的长期自动控制 ,解决增施CO2 过程中可能将空气中杂菌引入组培箱的问题 ,设计开发了一套基于PLC的无糖组培微环境控制系统。系统以PLC为控制核心 ,采用定量供给的CO2 增施控制策略 ,可根据设定要求将固定量的高压、高纯度CO2 气体直接供入组培箱 ,并可对组培箱内湿度进行调控。系统调试试验结果表明 ,控制系统能将光期组培箱内CO2 摩尔分数和相对湿度分别控制在 70 0～ 90 0 μmol·mol-1和80 %～ 92 %的目标范围内 ,达到了预期效果     

土壤Zn向白菜茎叶的转移能力

研究了采自福建不同地区的 26个土壤的Zn向白菜茎叶的转移能力.结果表明,虽然用DTPA提取的有效Zn与茎叶Zn含量之间无显著相关,但以DTPA有效Zn为基础的Zn转移系数与土壤有效Zn之间呈极显著的幂函数相关,这种幂函数相关将白菜茎叶Zn含量与土壤有效Zn联系起来.在土壤Zn与作物Zn含量无显著相关的情况下,可用Zn转移系数(DTPA基)与土壤有效Zn之间的幂函数关系估计土壤Zn的环境质量限量.     

几种利用方式下酸性硫酸盐土的环境风险及其连锁效应

研究并比较了不同利用方式下酸性硫酸盐土酸形态和铝形态的结构特征,分析了硫形态与酸形态、酸形态与铝形态之间的相关性。研究发现,酸性硫酸盐土的不同利用类型中,土壤酸度由大到小依次为:鱼塘塘基、荒稻田>稻田>荒旱地>改良稻田>蔗田>红树林迹地;活性铝含量由高到低依次为:荒旱地>鱼塘塘基、荒稻田>稻田>改良稻田>蔗田>红树林迹地。土壤酸度和铝形态含量的层间差异较为显著,多数随深度增加呈逐渐上升的趋势。酸性硫酸盐土中的硫形态—酸—铝形态之间有明显的连锁关系。     

内蒙古某铁矿尾矿库生态修复区的植被恢复效果

尾矿库生态修复可以在一定程度上阻隔库内污染物扩散，适宜植物种选择不仅有利于确保坝体地质安全，还是构建区域生态安全屏障的重要措施。本研究选取内蒙古某铁矿尾矿库的坝体边坡绿化、库外道路、人工湿地3个类型生态修复区，运用植物群落生态学的调查方法，分析与探讨了尾矿库外"边坡-道路-人工湿地"环境梯度下生态修复的适生植物种及物种多样性变化特征。结果表明：尾矿库生态修复区共发现植物31种，隶属13科30属，以菊科、豆科、禾本科和藜科为主，占总数的71.0%。边坡绿化区和库外道路区的草本优势种为狗尾草[Setaria viridis（L.）Beauv]、冰草[Agropyron cristatum（L.）Gaertn]、猪毛菜（Salsola collina Pall）、黄芪[Astragalus membranaceus（Fisch.）Bunge]，共有灌木优势种为白刺（Nitraria tangutorum Bobr）；人工湿地区的建群种为芦苇[Phragmites australis（Cav.）Trin.Ex Steud]。边坡绿化区物种多样性的Shannon-wiener指数（H值）和Pielou均匀度指数（J值）最高，分别为0.983和0.347，人工湿地区的H值和J值最低，分别为0.049和0.030；边坡-道路之间的相异性指数为0.647，道路-湿地之间的相异性指数为0.818，物种组成的替代速率前者大于后者。研究结果可以为相似类型的铁矿尾矿库生态修复的植物种选择和稳定群落构建提供参考。     

巢湖流域水污染控制决策GIS支持系统的建设

介绍了环境水污染控制决策GIS支持系统在安徽省巢湖流域水污染控制中的应用及研制过程,以及系统的基本结构、硬件环境、系统数据以及系统软件,分析了系统的技术特点和主要功能.     

毒绳在辽宁省义县地区应用的初探

广泛大量地应用杀虫药物进行卫生害虫的防治,不仅耗费大量的人力财力,也造成了环境的污染,还可使害虫对杀虫药物的抗性逐年上升。为了探索如何充分地利用现有的药物,使其发挥更大的效力,提高其防治水平。节省用药量,延缓抗性的发展,减少药物对环境的污染有着重要的意义。为此本文根据实验浅谈了应用毒绳灭虫的效果。"