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1.
常温下用水解法处理BF4废水.实验采用铝盐作主水解剂,试剂A作助水解剂,pH值小于3,在常温条件下实现了对BF4的高效水解.研究结果表明,BF4∶Al3+∶A的质量比为1∶0.8∶0.1,水解时间6~3h,水解率达到99.5%以上.使用助水解剂A,缩短了水解时间,减少了铝盐用量,对高浓度的BF4废水效果尤为显著,水解时间可缩短一半,主水解剂用量可减少1/5,处理后出水中的BF4含量可降到10mg/L以下.  相似文献   

2.
研究了除草剂哌草丹在土壤、水环境中的吸附、脱附、水解及光解过程.结果指出:哌草丹在土壤上的吸附主要受土壤有机质的影响,粘土矿也有一定作用.吸附和脱附均可用Freundlich方程描述;根据降解产物推测了哌草丹的水解和光降解的机理,哌草丹的水解产物为2苯基丙烯和六氢吡啶等,六氢吡啶可与土壤粘土矿(蒙脱石)作用,并与蒙脱石层间阳离子形成配合物;哌草丹光降解的产物为六氢吡啶、苯乙酮和甲醛  相似文献   

3.
新农药吡虫啉及其代谢产物对土壤呼吸的影响   总被引:22,自引:0,他引:22  
为评价吡虫啉对土壤生态环境造成的影响,用直接吸收法测定土壤呼吸强度,比较了吡虫啉浓度为0、10、40和100μg/g及40μg/g水解、光解产物的影响.结果表明高浓度吡虫啉对土壤呼吸的抑制作用较强,水解产物对土壤呼吸的影响小于吡虫啉,10min光解产物对土壤呼吸的影响要略强于吡虫啉,但30min光解产物对土壤呼吸的影响大大降低.13d后各处理的土壤呼吸强度基本恢复.吡虫啉及其代谢产物均属于低毒或无实际危害的农药,对土壤微生物影响较小.  相似文献   

4.
吡虫啉及代谢产物对土壤过氧化氢酶活性的影响   总被引:46,自引:2,他引:44       下载免费PDF全文
通过模拟试验研究了新农药吡虫啉及其代谢产物对土壤过氧化氢酶活性的影响结果表明,吡虫啉浓度不同对土壤过氧化氢酶活性影响也不同,浓度越高影响越强烈.在吡虫啉浓度为1,10,40μg/g时其影响过程是“先抑制-再恢复和激活-最后恢复稳定”,而在高浓度(150μg/g)吡虫啉作用下只经“激活恢复稳定”两个阶段.另外,吡虫啉的代谢产物(水解和光解产物)对土壤过氧化氢酶活性的影响均小于吡虫啉亲体,而且光照时间越长,对土壤过氧化氢酶活性的影响越小,即吡虫啉降解后会减弱对供试土壤填生态环境的影响.  相似文献   

5.
淮南选矸电解生产Al-Si-Ti合金的研究   总被引:2,自引:0,他引:2  
对淮南煤矸石低温焙烧酸浸脱杂并电解生产AlSiTi合金进行了研究.结果表明,采用该工艺生产AlSiTi合金切实可行,关键在煤矸石中杂质的脱除,焙烧温度是影响脱杂的主要因素,在300—450℃之间能取得最佳脱杂效果,其杂质总量由10%左右降低到15%以下;脱杂煤矸石在温度为1000℃左右、阴阳极电流密度分别为07和10A/cm2电解条件下能被还原并共同沉积形成合金,所得合金化学组成符合国家标准相应牌号合金的要求.  相似文献   

6.
研究了人体血红蛋白(Hb)与4氨基联苯(4ABP)加合物的测定方法.考察加合物的分离条件及定量测定加合物的精确度.研究人体血红蛋白的体外加合产物的生成量与反应时间的关系.体外实验结果发现,在37℃恒温条件下,12h之内,4ABP与Hb加合物的生成速率为126pg/(mg·h).  相似文献   

7.
考察了淀粉水溶液在兼性水解污泥中的水解吸附动力学过程。具体分析了淀粉水解过程包含的水解污泥吸附、胞外酶水解和水解产物降解3个阶段。并运用SPSS和MATLAB等数学统计软件对3个阶段的实验结果进行分析,使用多种拟合方法建立水解酸化过程中的动力学模型,通过数学模型尽可能解释和表征水解反应机理。分析结果表明:(1)水解污泥经驯化具有良好的吸附和水解性能。(2)对吸附平衡过程中的动力学方程拟合Lagergren的一级吸附速率方程和二级吸附速率方程都可以拟合淀粉吸附平衡过程,而二级吸附速率方程优于一级吸附速率方程。二级吸附速率方程可以计算出平衡吸附量,具有一定的优势。(3)对水解过程的实验数据进行多项式拟合可以得到四阶多项式方程。(4)淀粉水解产物降解反应为1级反应。反应速率常数为0.000569/min,反应动力学方程式St=826.628e^-0.000569。  相似文献   

8.
于洪锋 《环境科技》2007,20(A01):29-30
介绍了水解-酸化-好氧工艺处理染料生产废水。长期运行结果表明,当染料生产废水的COD质量浓度〈2000mg.L^-1时,在水解反应器、酸化反应器和曝气池的水力停留时间(HRD分别为7.0,7.0和6.0h的条件下,出水可以达到国家二级排放标准。水解-酸化过程提高了染料生产废水的可生化性,为后续好氧处理创造了条件。  相似文献   

9.
腈纶废丝的化学处理及产物的应用   总被引:1,自引:0,他引:1  
着重介绍了腈纶废丝的三种水解方式、工艺条件以及水解产物在材料制造、树脂合成、纺织印染、涂料粘合剂、石油和水处理等工业中的应用。同时 ,还介绍了腈纶废丝的溶剂化学处理、物理处理及其应用  相似文献   

10.
研究了在模拟太阳光和紫外光作用下,4氯苯酚(4CP)的光反应动力学.研究表明,紫外光的作用更为显著.4CP的反应速率与4CP起始浓度、pH值,金属离子浓度、富里酸浓度等因素有关.通入空气,能够加速4CP降解.  相似文献   

11.
The direct and sensitized photodegradations of imidacloprid, 1-(6-chloro-3-pyridinylmethyl)-N-nitro-2-imidazolidinimine, were investigated in aqueous solution and with and without various photo-sensitizers. Results of the study revealed that the intensity of lamp-house and irradiation wavelength had significant effects on the photolysis of imidacloprid. Complete degradation of 20 mg/L imidacloprid in aqueous phase was observed in 40 min under ultraviolet(UV) irradiation system, suggesting the ultraviolet ray played significant role in direct photolysis of imidacloprid. The additions of various photo-sensitizers lead to improve the degradation efficiency of imidacloprid under the irradiation of black light fluorescent lamp. TiO2 was the most efficient in the photo-catalytic degradation of imidacloprid among other photo-sensitizers in used this study. However, addition of acetone inhibited the photolysis of imidacloprid under the irradiation of UV, indicating the occurrence of competition between acetone and imidacloprid for photos. Mineralization of the imidacloprid was examined to clarify the final photochemical degradation products of the insecticide which were CO2, CI^- and NO3^-. Complete photo-oxidation of nitrogen to NO3^- occurred very slowlyvia the intermediate formation of NH4^ and NO2^- .  相似文献   

12.
生物质炭及老化过程对土壤吸附吡虫啉的影响   总被引:4,自引:2,他引:4  
通过批处理恒温振荡法,系统考察了土壤类型(熟化红壤、新垦红壤)、生物质炭种类(竹炭、稻草炭)、生物质炭用量(0、0.1%和0.5%,质量分数)及老化过程(恒湿30 d)对土壤吸附吡虫啉的影响.Freundlich曲线描述的研究结果表明,有机质含量高的熟化红壤对吡虫啉的吸附能力强于有机质含量低的新垦红壤.生物质炭的添加能增强土壤对吡虫啉的吸附能力,且吸附能力随生物质炭施用量的增加而显著提高.添加等量生物质炭,新垦红壤吸附吡虫啉能力的增强效果强于熟化红壤;在同种土壤中添加不同种类的等量生物质炭,新垦红壤添加稻草炭后吸附能力更强,熟化红壤添加竹炭后吸附能力更强.恒湿老化后的处理对吡虫啉的吸附能力与新鲜处理相比明显降低,且添加竹炭的处理比稻草炭处理受老化过程影响更大.  相似文献   

13.
IntroductionHydrolysisisthereactionofchemicalswithwaterandalsoanimportantenvironmentalprocessoforganicpollutants.Hydrolysisofsyntheticorganiccompoundsoccursviaseveralpathwayswhichinvolvethespecific acid , baseandneutralprocesses.Inaddition ,waterdissocia…  相似文献   

14.
附载TiO2光催化降解咪蚜胺农药   总被引:17,自引:0,他引:17  
以主波长365nm的黑炽荧光灯为光源,研究了由CMC-Na附载TiO2光催化降解咪蚜胺农药的过程。结果表明,咪蚜胺农药在3*8W黑炽荧光灯照射下,经附载TiO2作用3h后可降解50%以上,其光解可用假一级动力学方程表示。  相似文献   

15.
Imidacloprid is one of the most commonly used insecticides in agricultural practice, and its application poses a potential risk for soil microorganisms. The objective of this study was to assess whether changes in the structure of the soil microbial community after imidacloprid application at the field rate (FR, 1 mg/kg soil) and 10 times the FR (10× FR, 10 mg/kg soil) may also have an impact on biochemical and microbial soil functioning. The obtained data showed a negative effect by imidacloprid applied at the FR dosage for substrate-induced respiration (SIR), the number of total bacteria, dehydrogenase (DHA), both phosphatases (PHOS-H and PHOS-OH), and urease (URE) at the beginning of the experiment. In 10× FR treated soil, decreased activity of SIR, DHA, PHOS-OH and PHOS-H was observed over the experimental period. Nitrifying and N2-fixing bacteria were the most sensitive to imidacloprid. The concentration of NO3- decreased in both imidacloprid-treated soils, whereas the concentration of NH4+ in soil with 10× FR was higher than in the control. Analysis of the bacterial growth strategy revealed that imidacloprid affected the r- or K-type bacterial classes as indicated also by the decreased eco-physiological (EP) index. Imidacloprid affected the physiological state of culturable bacteria and caused a reduction in the rate of colony formation as well as a prolonged time for growth. Principal component analysis showed that imidacloprid application significantly shifted the measured parameters, and the application of imidacloprid may pose a potential risk to the biochemical and microbial activity of soils.  相似文献   

16.
为了明确混凝过程中搅拌剪切等动力学因素对铝盐水解聚合反应平衡的影响,采用配制模拟水样作为混凝水系,用Ferron逐时络合比色法对水解产物形态进行表征,并将获取结果与用去离子水组成的纯净水系获取的结果进行对比分析.同时,研究了模拟混凝水系中搅拌剪切条件对铝盐水解反应产物形态分布的影响,考查了铝盐的碱化度和模拟混凝水系的pH值对混凝体系中搅拌剪切条件作用于铝盐水解产物形态分布的影响,并提出了体系搅拌剪切条件影响混凝水系中铝盐水解反应平衡的作用机理.结果表明,混凝过程中的铝盐水解产物形态分布明显受到体系搅拌剪切条件的影响,并且随着混凝水系中铝盐水解程度的增大和转化率的提高,铝盐的水解产物形态分布受到反应体系中搅拌剪切条件的影响加大.  相似文献   

17.
单甲脒盐酸盐的酸性、中性和碱性水解的动力学过程   总被引:3,自引:0,他引:3  
单甲脒盐酸盐的酸性、中性和碱性水解的动力学过程颜文红,雷志芳,叶常明(中国科学院生态环境研究中心,北京100085)关键词:单甲脒盐酸盐;水解;酸碱度。1引言单甲脒碱,化学名称为N—(2,4-二甲苯基)—N'-甲基甲脒,简称DMA,是一种新型高效的有...  相似文献   

18.
The effects of polyaluminum chloride (PACl) hydrolysis prior to coagulation on both the coagulation zone and coagulation performance of a kaolin suspension were investigated by a novel jar test named the “reversed coagulation test”. The tests showed that PACl hydrolysis prior to coagulation decreased the performance of charge neutralization coagulation in the case of short-time slow mixing (10 min; G = 15 sec ?1 ) and increased the optimal dosage for charge neutralization and sweep coagulation. Moreover, the hydrolysis time had insignificant effects on the size and zeta potential of PACl precipitates and the residual turbidity of the raw water. However, PACl hydrolysis prior to coagulation and the size of PACl precipitates had a negligible effect on the performance of sweep coagulation.The results imply that, in practice, preparing a PACl solution with deionized water, rather than tap water or the outlet water from a wastewater treatment unit, can significantly save PACl consumption and improve the performance of charge neutralization coagulation,while preparing the PACl solution with tap or outlet water would not affect the performance of sweep coagulation. In addition, the optimal rapid mixing intensity appears to be deter-mined by a balance between the degree of coagulant hydrolysis before contacting the primary particles and the average size of flocs in the rapid mixing period. These results provide new insights into the role of PACl hydrolysis and will be useful for improving coagulation efficiency.  相似文献   

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