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排序方式: 共有35条查询结果,搜索用时 78 毫秒
1.
建立了同时测定皮革中邻苯基苯酚和7种含氯苯酚的GC-MS联用分析方法。采用甲醇为溶剂,超声萃取皮革中的苯酚类物质,蒸发浓缩后,用乙酸酐乙酰化,正己烷萃取,经浓缩和定容后,用GC-MS测定,外标法定量。结果表明,目标物质在0.02~0.30 mg/L范围内的线性关系良好,相关系数为0.998 9~0.999 9,平均回收率为89%~106%,相对标准偏差(n=7)为1.8%~8.8%;方法的定量下限低于0.01 mg/L。方法简便、高效、准确、灵敏,可满足进出口皮革和皮革制品中多种苯酚类物质的检测需求。  相似文献   
2.
A novel azo dye ligand, 2,2′‐(1,3‐phenylenebis(diazene‐2,1‐diyl))bis(4‐chlorophenol), was synthesized from the diazotization of m ‐phenelyenediamine and coupling with p chlorophenol in alkaline medium. Mononuclear Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of the azo ligand (H2L) were prepared and characterized using elemental analyses, infrared spectroscopy, electron spin resonance, magnetic susceptibility, conductance measurements and thermal analyses. The UV–visible, 1H NMR and mass spectra of the ligand and its chelates were also recorded. The analytical data showed that the metal‐to‐ligand ratio in the mononuclear azo complexes was 1:1. Diffuse reflectance and magnetic moment measurements revealed the complexes to have octahedral geometry. The infrared spectral data showed that the chelation behaviour of the ligand towards transition metal ions was through phenolic oxygen and azo nitrogen atoms. The electronic spectral results indicated the existence of π → π* (phenyl rings) and n → π* (─N═N) and confirmed the mentioned structure. Molar conductivity revealed the non‐electrolytic nature of all chelates. The presence of water molecules in all complexes was supported by thermal studies. Molecular docking was used to predict the binding between H2L and the receptors of breast cancer mutant 3hb5‐oxidoreductase, crystal structure of Escherichia coli (3 t88) and crystal structure of Staphylococcus aureus (3q8u). The molecular and electronic structure of H2L was optimized theoretically and the quantum chemical parameters were calculated. In addition, the effects of the H2L azo ligand and its complexes on the inhibition of bacterial or fungal growth were evaluated. The prepared complexes had enhanced activity against bacterial or fungal growth compared to the H2L azo ligand.  相似文献   
3.
王华静  傅尧  王晨  郭庆祥 《化学学报》2008,66(3):362-370
利用六种密度泛函理论方法(B3LYP, B3P86, MPW1K, TPSS1KCIS, X3LYP, BMK)对碳氯键离解能进行理论计算,结果发现几种新发展的密度泛函(DFT)方法用于碳氯键离解能的计算比传统的B3LYP有较大的改善,其中对能量估算相对准确的B3P86方法对碳氯键离解能的计算精度最高,对17个分子中碳氯键离解能计算的平均绝对偏差为6.58 kJ/mol。最后运用B3P86方法对一系列环境危害较大,但可通过光化学降解和生物降解的氯代有机物的碳氯键离解能值进行预测,并讨论了影响碳氯键离解能的结构性质关系。  相似文献   
4.
TiO2光催化降解4-氯苯酚过程中的电分析监测   总被引:3,自引:0,他引:3  
采用循环伏安法和紫外光谱法对有机物的光催化降解进行机理研究和在线监测.以标准光催化剂DegussaP25在紫外光照射下催化降解4-氯苯酚,发现在降解过程中至少有两对氧化还原中间产物对苯二酚-苯醌和羟基氢醌-羟基苯醌.由4-氯苯酚及中间产物的电极响应,可以观测到它们在光催化降解过程中的含量变化,从而对整个过程实现在线监测,并由此全面了解光催化反应机理.从不同反应时间后测得的紫外光谱可以看到,苯环特征峰逐渐消失.这表明4-氯苯酚的苯环逐渐被打开,直至被彻底降解.  相似文献   
5.
毛细管区带电泳分离测定邻、对、间氯代苯酚   总被引:3,自引:0,他引:3  
李珺  袁倬斌 《分析化学》2001,29(12):1416-1418
通过改变电泳条件,用毛细管区带电泳成功地分离了邻、对、间氯代苯酚,并检测到废水中样品的含量。研究了缓冲溶液种类、浓度、pH值、电泳电压以及内标物的选择,并得出了三种样品的标准曲线、线性范围以及加样回收率,为环境样品的监测提供了依据。  相似文献   
6.
4-氯酚稀水溶液的脉冲辐解研究   总被引:10,自引:0,他引:10  
利用脉冲电子束进行了多种条件下4-氯酚稀水溶液的脉冲辐解研究,对其瞬态光谱中的主要吸收峰作了归属,并初步考察了这些瞬态物种的生长、衰减等行为,研究表明,·OH基与4-氯酚在碱性条件下反应生成氯代酚氧基,速率常数为4.14×10^9L/(mol·s),在酸性条件下要经过OH-adducts;H原子与4-氯酚反应生成H-adducts的速率常为2.0×10^9L/(mol·s),产物可通过双分子二级反应逐步脱氯;eaq^-可直接从4-氯酚分子夺氯,反应速率常数为1.82×10^9/L(mol·s)。  相似文献   
7.
李海玉  张庆  康苏媛  吕庆  白桦  王超 《色谱》2012,30(6):596-601
建立了固相萃取-气相色谱-质谱(SPE-GC-MS)检测含氯酚类化合物(2,4-二氯苯酚、2,4,6-三氯苯酚、2,4,5-三氯苯酚、2,3,4,6-四氯苯酚、五氯苯酚、林丹)和菊酯类化合物(氯菊酯、氟氯氰菊酯、氯氰菊酯、溴氰菊酯)等10种木材防腐剂的方法。对家具样品采用超声萃取法、以甲醇为提取剂在室温下反复提取2次,提取液经浓缩后,加入碳酸钾和乙酰酐衍生化,将衍生化后的溶液通过Oasis HLB固相萃取柱净化,用乙酸乙酯洗脱并收集检测。采用该方法实现了家具中10种木材防腐剂的分离检测,该方法中氯酚类防腐剂定量限为1 mg/kg、菊酯类防腐剂定量限为5 mg/kg,平均回收率为76.0%~108.8%。应用该方法对市场上销售的木制家具进行了检测,在部分家具中检出含有少量林丹。实验结果证明,该方法准确、灵敏,可有效地应用于木制家具中防腐剂的实际检验工作中。  相似文献   
8.
A series of metal oxide catalysts for catalytic oxidative degradation of 2-chlorophenol (2-CP) and 4-chlorophenol (4-CP) were prepared, and the supported CuO catalysts were studied particularly. The supported CuO catalysts were characterized by XRD and NH3-TPD techniques, in which CuO/γ-Al2O3 exhibited high degradation activity. The addition of Na2O or K2O into CuO/γ-Al2O3 improved the oxidative degradation of CPs remarkably, in which Na2O was more efficient than K2O. Over CuO/γ-Al2O3-Na2O, CPs were completely converted and the liberation of the inorganic chloride from 2-CP or 4-CP reached 97% or 100% respectively at 30 ?C for 2 h. The supported CuO catalysts with good dispersion of CuO particles and less acid sites were favorable for the efficient oxidative degradation of CPs. In addition, the initial pH of the reaction solution was found to be an important factor which influenced the catalytic oxidative degradation of CPs and the initial pH of 11.2 and 9.8 was preferred for the oxidative degradation of 2-CP and 4-CP respectively over CuO/γ-Al2O3 catalyst.  相似文献   
9.
5-[2-(4-氯苯酚)偶氮]-若丹宁与铂(Ⅱ)的显色反应研究及应用   总被引:11,自引:1,他引:11  
研究了新显色剂5-[2-(4-氯苯酚)偶氮]-若丹宁与铂(Ⅱ)的显色反应.在H2SO4-H3PO4介质中和CTMAB存在下,试剂与Pt(Ⅱ)形成有色配合物,λmax位于426nm,摩尔吸光系数为3.24×105L·mol-1·cm-1,Pt(Ⅱ)量在4.00~10μg/25mL符合比耳定律,方法用于铂催化剂中铂的测定,获得较好的结果.  相似文献   
10.
Photosensitized oxidation of 4-chlorophenol (4CP) by the title complexes (AIPcS and ZnPcS) in aerated aqueous solution uponvisible light irradiation(λ=450nm) has been investigated using methanol as a disassociating reagent.It is confirmed that the monomeric species of the sesitizer is more active than the corresponding dimer in singlet oxygen generation for 4CP oxidation.However,the monomer is also the main component found in the sensitlzer‘s photobleaching, In this reload, AIPcS is much more stable than ZnPcS, and the Dhotoble~hlno is observed to proceed via singlet and triplet oxygen, respectlvely.The final products of 4CP oxidation in alkaline solution are carbon dioxide and chloride ions.while at pH=7 and pH=3 the p-benzoquinone is the product.The temperature is found to have influence on both the photosensitized degradation of methyl orange and ZnPcS photobleaching,with an activation energy of 15.8 and 24.2kJ/mol,respectively.  相似文献   
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