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1.
测定了27种取代苯类化合物在松花江江水中的生物降解性,采用量子化学MOPAC6.0-AM1法计算了化合物的分子量(MW),生成热(Hf),分子总表面积(TSA)及高占有轨道能(EHOMO),结合辛配醇/水分配系数lgP及酸解离常数pKa对其中22种化合物BOD值进行了多元线性回归分析,得到如下模型:BOD=105.73-0.439MW-0.076Hf-6.660lgP n=22,R^2=0.821,SE=8.250,F=27.56,P=0.000应用所得模型对其余5个化合物的生物降解性进行了预测,只有一个化合物相的相对预测误差大于20%,为20.8%,平均预测误差为12.4%。  相似文献   

2.
有机化合物厌氧生物降解性的测定和预测   总被引:7,自引:0,他引:7  
韩朔睽  张爱茜 《环境化学》1995,14(3):200-205
测定有机物厌氧生物降解性的方法包括非特性参数和特性参数测定法。本文着重介绍有机物厌氧生物降解性的筛选测定法,以基团贡献法为基础,不外加其它理化参数的有机物结构与生物降解性关系的预测已经由简单的线性模型发展至专家系统和人工神经网络模型,并显示出极好的应用前景。  相似文献   

3.
偶氮染料定量结构-生物降解关系(QSBR)研究   总被引:5,自引:0,他引:5  
利用量子化学原理剖析了偶氮染料的脱色机制,所得结果与文献中关于染料结构与脱色能力之间关系的结论基本一致,以脱色能力为染料生物降解能力的表征,建立了定量结构生物降解性模型,模型预测结果与实验结果基本吻合。  相似文献   

4.
生物降解性是评估污染物环境持久性的重要依据,也是化学品是否获准生产及进入市场的评价指标。采用17位生物降解领域专家评估的生物降解等级数据,通过功能树(FT)算法建立了包含15个分子结构参数的初级生物降解和最终生物降解预测模型。外部验证结果表明,模型具有较好的预测准确性,初级生物降解性加权准确度(weighted accuracy,WA):训练集WA=84.1%,验证集WA=78.9%;最终生物降解性WA:训练集WA=91.0%;验证集WA=83.6%。预测正确性对化合物的杠杆值作图,表征了生物降解性模型的应用域。  相似文献   

5.
偶氮染料定量结构—生物降解关系(QSBR)研究   总被引:1,自引:0,他引:1  
戴树桂  宋文华 《环境化学》1998,17(2):115-119
利用量子化学原理剖析了偶氮染料的脱色机制,所得结果与文献中关于染料结构与脱色能力之间关系的结构基本一致,以脱色能力为染料生物降解能力的表征,建立了定量结构-生物降解性模型,模型预测结果与实验结果基本吻合。  相似文献   

6.
基于基团贡献法的有机化合物好氧生物降解预测模型研究   总被引:1,自引:0,他引:1  
从MITI-Ⅰ试验中筛选出587种不同类型有机化合物的可用数据,通过对这些物质的结构进行拆分,随机选择其中50种化合物作为验证集,另外537种作为训练集,利用多元线性回归(MLR)和支持向量机(SVM)2种计算方法分别建立模型。结果表明,芳香酸、醛、芳香碘和叔胺等功能基团对有机化合物的好氧生物降解性影响较大;MLR模型总体预测正确率为81.43%,验证集正确率为82%,SVM模型总体预测正确率为87.90%,验证集正确率为86%。所建立的2种定量结构与生物降解性关系(QSBR)模型有效,可用于化学品的好氧生物降解性评价。  相似文献   

7.
合成有机物结构—生物降解性关系的研究   总被引:2,自引:0,他引:2  
戴树桂  庄源益 《环境化学》1995,14(4):354-364
本文综述了合成有机物生物降解性的研究方法,以及定性结构-生物降解性关系(SBR),重点综述了芳香类化合物的结构与生物降解性的关系,研究这一关系有助于有毒化学品生物降解性的预测。  相似文献   

8.
部分取代苯类在江水中的生物降解与结构相关性研究   总被引:2,自引:0,他引:2  
测定了27种取代苯类化合物在松花江江水中的生物降解性.采用量子化学MOPAC6.0-AM1法计算了化合物的分子量(MW)、生成热(Hf)、分子总表面积(TSA)及最高占有轨道能(EHOMO),结合辛醇/水分配系数lgp及酸解离常数pKa对其中22种化合物的BOD值进行多元线性回归分析,得到如下模型:BOD=105.73-0.439MW-0.076Hf-6.660lgPn=22,R2=0.821,SE=8.250,F=27.56,P=0.000应用所得模型对其余5个化合物的生物降解性进行了预测.只有一个化合物的相对预测误差大于20%,为20.8%.平均预测误差为12.4%.  相似文献   

9.
戴树桂  宋文华 《环境化学》1998,17(2):105-114
本文通过分析影响有机物生物降解的基本因素,指出QSBR模型应综合反映影响有机物生物降解的四个方面:取代化合物的摄入、取代化合物的诱导作用,毒性物质的形成和基础酶的缺乏,在此基础之上给出了动态QSBR的概念模型及方法学基础,并利用其研究了氯代芳香化合物的生物降解性。  相似文献   

10.
酚类化合物的三维-定量结构与生物降解性关系(3D-QSBR)   总被引:2,自引:0,他引:2  
利用比较分子场分析法(CoMFA)研究了32种酚类化合物的生物降解性与其结构间的三维定量关系,并利用分子场聚焦(Region Focus)和调整网格大小对模型进行改善,得到具有较强预测能力的3D-QSBR 模型.结果表明:进行分子场聚焦和减小网格步长(Grid Spacing)均可改善模型质量,得到的最佳模型主成分数为4,交叉验证相关系数Q2为0.587,复相关系数R2为0.917,F值为57.654.  相似文献   

11.
The formation of aromatic amines was investigated using a summarized test (NEDA-test) during the composting of 2,4,6-trinitrotoluene (TNT) contaminated soil. In this test, the aromatic amines were diazolated and then coupled to N-1-Naphthyl-ethylenediamine-dihydrochloride (NEDA) to yield an azo dye which can be monitored photometrically. The test was calibrated for known TNT-metabolites with an active amine-group. Liquid samples from composting- and liquid-culture-experiments were analyzed by HPLC for these known metabolites. Moreover, the samples were monitored by the NEDA-test and the expected extinction of the TNT-metabolites found with amine function were extrapolated with the help of calibration curves. It was shown that substantial differences are obvious between the monitored and extrapolated values. After separation into polar and non-polar aromatic amines, it became clear that these differences are made by the polar aromatic amines. Polar aromatic amines, which are not detectable by presently available analytical tests, were generated during the composting of TNT-contaminated soils. Contaminated stagnant water, which was generated during anaerobization of a compost prephase, was treated aerobically for 70 days in a biofermenter. During this treatment TNT and its known metabolites were eliminated almost entirely. Simultaneously, the toxicity in the Lumis Tox-test decreased drastically. In striking contrast, the sum of aromatic amines decreased only to a minor extent. Moreover, the percentage of polar compounds from total amount of aromatic amines increased drastically from 48% to more than 95%. At present, the chemical identification of these polar compounds is still missing and is the object for further research.  相似文献   

12.
批量平衡法研究芳香族酮类化合物在东北黑土中的吸附   总被引:9,自引:0,他引:9  
本文用批量平衡法研究-系列芳香族酮类化合物在东北黑土中的吸附,采用Fre-nundlich吸附等温方程求得土壤吸附常数(kf),研究表明:12种芳香族酮类化合物的吸附等温线有线性和非线性两种形式,对化合物的土壤有机碳吸附常数(lgKoc)进行定量结构-性质(QSPR)分析,发现芳香族酮类化合物的土壤有机碳吸附常数与正辛醇/水分配系数相关不显著,土壤有机碳吸附常数与分子极化率(a)有较好的相关性,这  相似文献   

13.
In this study, kinetics of photocatalytic degradation of phenolic wastewater in immobilized photocatalytic reactor was investigated. Immobilization of titanium dioxide (TiO2) nano powders on concrete surfaces were accomplished with epoxy concrete sealer. Kinetics of photocatalytic reactions has been proposed to follow the Langmuir–Hinshelwood model in different initial phenol concentration, pH, and UV lamp intensity. First-order reaction kinetics with respect to the pollutant concentration was obtained for the reaction. Effect of UV lamp intensity showed that kinetic constants were proportional to the power of 0.73–1 of the photonic flow. In all cases kinetic constant increases as pH of the system reached up to 12 units. Several reaction intermediates were identified using the GC/Mass analysis. Products at the initial stage of the reaction were aromatic compounds, contained hydroquinone, benzoquinone, and catechol. These intermediates underwent further photocatalytic oxidation to aliphatic compounds and finally into CO2 and H2O after 4?h. Kinetic constants of intermediate compounds were determined using mathematical–chemical equations and nonlinear regression. Data showed that the differences between the mathematical model and Langmuir–Hinshelwood model for the kinetic constant was less than 5%.  相似文献   

14.
32种芳香化合物的好氧生物降解性表征   总被引:6,自引:0,他引:6  
本文采用芳香化合物生物降解产生的二氧化碳量作为表征其生物降解性的指标,测定了32囊芳香化合物好氧生物降解12d产生的二氧化碳量,在此基础上提出了定性划分有机物生物降解性的标准,按照此标准对32种芳香化合物的生物降解性进行了划分;另外还探索了影响生物降解性的诸因素。  相似文献   

15.
吴顺年  苑会梅 《环境化学》1994,13(4):346-353
本文利用紫外分光光度法测定了多种取代芳烃在有机溶剂与水组成的共溶剂体系中的溶解度。实验结果表明:溶质溶解度的对数与有机溶剂的体积分数呈良好的线性关系;利用对数线性模型,以及UNIFAC基团贡献法对溶质的溶解度进行了估算,发现估算值与测定值吻合得较好。  相似文献   

16.
应用模式识别法研究芳腈化合物结构与活性的关系   总被引:2,自引:0,他引:2  
韩朔睽  许榕 《环境化学》1995,14(3):279-283
基于23个芳腈衍生物对发光菌的毒性疚和一批结构参数,用模式识别法研究了结构与活性的关系。在化合物的生物活性类别与模式特征之间建立的3个类别判别函数对化合物活性类别的判别正确率达91.3%,并为进一步的研究工作合理地挑选了4个代表性化合物。  相似文献   

17.
合成有机化合物的生物降解性研究   总被引:27,自引:2,他引:27  
王菊思  赵丽辉 《环境化学》1993,12(3):161-172
合成有机化合物的生物降解性研究,为预测各类化合物在环境中的滞留与影响,为某些化合物的生产、实用及向环境中排放提供立法的依据,以及对开发更有效的生物处理技术均有重要意义。本文从合成有机化合物生物降解性研究的意义、研究方法、化合物化学组成和结构与生物降解性的关系等方面,介绍了国内外研究工作的进展情况,并对苯及烷基苯类、芳香酸及其脂类、酚类、含氯有机物和含氮芳香化合物的生物降解规律和降解途径进行了综述。  相似文献   

18.
In this study, the removal of color, chemical oxygen demand (COD) and aromatic group from one of the azo dyes, Remazol Yellow RR Gran, had been carried out by using one of the white rot fungi, Phanerochaete chrysosporium. Experimental studies were performed in growth media containing different amounts of dye and glucose. Color measurements were done at 436nm wavelength using spectrophotometer while aromatic group measurements were done at 280 nm wavelength using UV/Visible spectrophotometer. As a result of this study the values of the removable color concentration were determined as 10 mgl(-1) and lower. The optimum medium glucose concentration was determined to be 2 gl(-1) during color removal processes, aromatic group measurements were done in samples in the UV region at 280 nm wavelength. As a result of the measurements, it was shown that certain amount of aromatic group remained in the model wastewater at the end of the process.  相似文献   

19.
白腐菌对芳香化合物的降解   总被引:13,自引:2,他引:13  
林鹿  张干 《环境化学》1999,18(5):408-413
本文研究了纯培养条件下白腐菌对一些芳香化合物的降解规律,并探讨了影响白腐菌降解芳香化合物的因素如取代基位置、数量以及对难降解芳香化合物的共代谢解过程。  相似文献   

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