模拟沉积磷迁移转化行为的铁盐影响机制研究

室内模拟研究了沉积物中不同形态磷在不同浓度铁盐影响下,在沉积层中的垂直迁移转化行为.结果表明,分别向模拟系统投加的10 mL和50 mL的1 mol/L FeCl_3溶液,沉积层中磷的含量降低,投加30 mL的1 mol/L FeCl_3溶液时,沉积层中磷含量增加.沉积物中适当的铁盐会阻止沉积物磷向水体释放,铁盐浓度过高或过低,在一定程度上都会促进沉积物中磷的释放,实验结果对研究内源磷释放与湖泊富营养化有重要的意义.     

商陆和烟草对锰胁迫的抗氧化响应研究

研究植物的重金属累积能力对于植物修复和植物冶金意义重大.Mn超累积植物商陆(Phytolacca americana L.)的耐性/累积机制至今还不清楚,为了研究商陆在Mn胁迫下的抗氧化酶作用,将萌发6周的商陆和烟草幼苗分别放入1 mmol·L~(-1)或3 mmol·L~(-1)的1/2 Hoagland营养液处理4 d,实验表明商陆叶片光合速率降低幅度显著低于烟草,而烟草MDA含量和电解质渗漏量增加幅度大于商陆.如1 mmol·L~(-1) Mn处理4 d后,与对照相比,商陆和烟草的光合速率分别降低13.3%和75.5%;烟草MDA含量和电解质渗漏量分别增加347.3%和120.1%,而商陆的MDA含量和电解质渗漏量没有明显增加,表明Mn胁迫对超累积植物引起的氧化损伤明显低于非累积植物.随着Mn处理浓度的提高和时间的延长,2种植物叶片SOD和POD活性均迅速增加,其中商陆SOD活性的增加幅度大于烟草;另外,商陆CAT活性持续上升,而烟草CAT活性显著下降.如在1 mmol·L~(-1) Mn处理下,商陆SOD、POD和CAT活性分别提高161.1%、 111.3%和17.5%;烟草SOD和POD提高55.5%和206.0%,而CAT下降15.6%,表明商陆的抗氧化酶,特别是CAT,能够有效地清除Mn毒产生的自由基.这些结果说明抗氧化酶的抗氧化能力是重金属累积植物商陆的Mn耐性机制之一.     

Significance of iron compounds in chemical and electro‐oxidation treatment of sugar industry wastewater: Batch reaction

Industrialization plays a major role in a nation's growth. However, with an increase in industrial activities, pollution levels are also increasing. Among all industries, the sugar‐processing industry is one that requires large amounts of water to process the sugar, and, consequently, it discharges large amounts of water as effluent. Highly polluted wastewater brings changes to the physicochemical characteristics of the surrounding environment. Iron compounds have had a significant impact when they are used in wastewater treatment in various applications, including when they are used to minimize the pollution levels in sugar industry wastewater (SIWW). To minimize the pollutant levels from SIWW, iron compounds have been key for uses in treatments involving chemical and electro‐oxidation. Two different methodologies of electrocoagulation and chemical coagulation have been used to treat SIWW. In electrocoagulation, an iron plate is used as an electrode material under specific operating conditions. Ferrous sulfate and ferric chloride have been used as chemical coagulants at various pH and mass loading levels. The use of iron metals shows an 82% reduction in chemical oxygen demand (COD) and an 84% reduction in color at the optimum condition of pH 6, an electrode distance of 20 millimeters, and a current density of 156 square centimeters. As a chemical coagulant, iron salt (ferrous sulfate) provides a reduction of 77% COD and a 91% reduction of color at pH 6 and a 40‐millimole mass loading. Electrochemical treatment using iron was found to be suitable to treat SIWW. The sludge generated after treatment can be burned or composted with the possible recovery of some of the treatment costs.     

商陆耐重金属Cd关键酶抗氧化酶的研究

研究商陆(Phytolacca americana L.)对Cd胁迫的抗氧化酶响应,对于揭示其耐Cd机制具有重要意义.商陆幼苗在200μmol/L或400 μmol/L CdCl2营养液中处理4 d,叶片活性氧自由基和MDA含量升高,膜透性增加,光合速率降低,表明Cd胁迫诱导产生氧化胁迫.随着Cd处理含量的提高和时间的...     

盐雾试验方墨探讨

分析了不同盐雾试验方法标准对盐溶液配制、试样的处理和检测、试验参数、试验过程控制等方面的不同要求,探讨了盐雾试验的操作技术,提出了必须严格控制盐雾试验过程的建议和不能用不同标准进行的盐雾试验结果进行比较的观点.     

多铵复合盐分离工艺热工优化研究

多铵复合盐分离方法是利用纯物理的方法对焦炉煤气进行处理并分离出相应的盐类,在冷却结晶的过程中,从提高物料终冷温度的角度,对该方法进行相应的节能分析。一方面可以为当前生产提供节能改造依据,另一方面可以为该方法在大规模生产中的应用提供理论依据。     

不同耐性作物中几种酶活性对Cd胁迫的反应

为探讨作物对重金属毒害的耐受机理,本文采用盆栽试验及生理生化分析方法,研究了作物体内酶系统在耐受Cd胁迫中的作用。结果表明,在Cd胁迫下,耐性作物体内,SOD和PPO的活性未受明显影响或活性略增强,CAT活性明显增强;POD及硝酸还原酶活性的变化无明显规律。这说明,SOD、CAT和PPO活性的维持和提高是作物耐受Cd胁迫的物质基础之一。     

电化学法处理含盐染料废水

研究了电化学法处理含盐染料废水的可行性及其处理效果．结果表明,电化学法对废水的色度和COD具有良好的去除效果,电解过程中余氯的产生对色度和COD的去除有决定性作用．实验确定的高浓度含盐废水电化学处理条件为：电流密度0．017A/cm²,电压10．3V,平均电导率12．35ms/cm,电解60min,色度和COD的去除率分别为85％和99．8％．电解过程无难以继续反应的中间产物生成．     

Heavy Metal Toxicity Responses of Two Willow (Salix) Varieties Grown Hydroponically: Development of a Tolerance Screening Test

The E.U. funded BIORENEW project is investigating bioremediation of industrially degraded land using biomass fuel crops, including willow. One of its goals is to develop a rapid screening test to assess the metal tolerance of large numbers of willow varieties. This should reflect how a plant will respond to heavy metals under various field conditions and in the long term. A preliminary experiment tested two varieties of contrasting ability to thrive in metal-contaminated soils. Trees were exposed to a metal cocktail in three different strengths of background solution. An appropriate strength solution (1/4 strength Hoaglands) was identified for differentiating variety performance, based on its effect on the biomass of plant fractions relative to control fractions. This is a response to heavy metals which can be quantified rapidly and simply. The relative performance of the varieties was comparable to their performance in field studies. This test will be used to assess the tolerance of further varieties.     

水杨酸对小麦高盐毒害的缓解作用

以盐敏感品种中国春、农大８５０２１和抗盐品种冬６８、茶淀红等４个品种小麦（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．）为材料,研究盐分胁迫对小麦种子萌发和幼苗生长的影响以及水杨酸对盐害的缓解作用．结果表明,水杨酸能够相对提高盐分胁迫条件下小麦种子萌发的数量、速度和质量;提高幼苗根和叶内游离脯氨酸、可溶性糖等渗透调节物质的含量,增强其渗透调节能力,同时提高幼苗体内超氧化物歧化酶、过氧化物酶等细胞保护酶的活性,抑制膜脂过氧化作用产物丙二醛的积累,降低叶片质膜透性和盐分胁迫对细胞膜的伤害．所有这些变化都有利于缓解盐害,提高小麦抗盐性