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1.
气相色谱–质谱法测定塑胶中8种苯并三唑紫外吸收剂   总被引:1,自引:0,他引:1  
以气相色谱–质谱联用法测定塑胶中8种苯并三唑紫外吸收剂的含量。采用甲苯作为萃取溶剂,对样品进行超声萃取,选用DB–5HT气相分离色谱柱,以气相色谱–质谱联用仪对塑胶制品中8种苯并三唑类紫外吸收剂(UV–P,UV–320,UV–326,UV–327,UV–328,UV–329,UV–234,UV–360)进行分析测试。在优化的前处理和仪器分析条件下,8种苯并三唑紫外吸收剂萃取效果良好,在17 min内有效分离,色谱峰理想。在0.1~10 mg/L范围内溶液的质量浓度与色谱峰面积线性良好,线性相关系数(r~2)均大于0.999,检出限为0.1 mg/L,重复性试验相对标准偏差小于3%(n=7),加标回收率为95%~110%。该方法简便快捷、准确可靠,满足苯并三唑紫外吸收剂的检测要求。  相似文献   

2.
SA (sulfamic acid) catalyzes the reaction of indole with aldehyde and ketone to afford bis(indol-3-yl)methanes in good to excellent yields under solvent-free condition at ambient temperature.  相似文献   

3.
Two series of 7‐arylazo‐7H‐3‐(2‐methyl‐1H‐indol‐3‐yl)pyrazolo[5,1‐c][1,2,4]triazol‐6(5H)‐ones 4 and 7‐arylhydrazono‐7H‐3‐(2‐methyl‐1H‐indol‐3‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazines 7 were prepared via reactions of 4‐amino‐3‐mercapto‐5‐(2‐methyl‐1H‐indol‐3‐yl)‐1,2,4‐triazole 1 with ethyl arylhydrazono‐chloroacetate 2 and N‐aryl‐2‐oxoalkanehydrazonoyl halides 5 , respectively. A possible mechanism is proposed to account for the formation of the products. The biological activity of some of these products was also evaluated.  相似文献   

4.
An aniline derivative which corresponds to UV-5 in the preceding paper was isolated from the case L-tryptophan sample associated with eosinophilia-myalgia syndrome (EMS). By spectroscopic analyses, the structure was identified as 3-anilinoalanine. The compound was optically active, and the stereochemistry of alanine moiety was determined as L, by comparing the specific rotation with a synthesized 3-anilino-L-alanine.  相似文献   

5.
基于肝素和多硫酸软骨素(OSCS)在单糖组成上的差别,建立了可用于肝素中OSCS检测的柱前衍生高效液相色谱法.采用3 mol/L三氟乙酸,将受污染的问题肝素在110℃下充氮封管水解4 h,在碱性条件下与1-苯基-3-甲基-5-吡唑啉酮进行衍生化反应,再采用C18反相色谱柱,以0.1 mol/L磷酸盐(pH=6.7)缓冲液/乙腈(体积比82∶18)为流动相,在流速1.0 mL/min、柱温25℃及紫外检测波长245 nm的条件下进行液相色谱分析.结果表明,肝素和OSCS的单糖色谱峰具有良好的分离度,测得2批问题肝素中OSCS杂质的质量分数分别为19.6%和28.3%.该方法具有良好的精密度和重现性,易于推广,适合于肝素中OSCS杂质的检测,并可用于硫酸软骨素A和C与硫酸软骨素B的区分和鉴别.  相似文献   

6.
Triphenylphosphine (TPP) has been utilized as a novel and efficient catalyst for the Knoevenagel condensation of indole‐3‐carboxaldehydes 1(a–e) , 1‐methyl‐1H‐indole‐3‐carboxaldehydes 4(a–e) , and 1‐ethyl‐1H‐indole‐3‐carboxaldehydes 6(a–e) with the active methylene compound, that is, meldrum's acid ( 2 ), to afford substituted derivatives 5‐((1H‐indol‐3‐yl) methylene)‐2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione 3(a–e) , 2,2‐dimethyl‐5‐((1‐methyl‐1H‐indol‐3‐yl)methylene)‐1,3‐dioxane‐4,6‐dione 5(a–e) , and 2,2‐dimethyl‐5‐((1‐ethyl‐1H‐indol‐3‐yl)methylene)‐1,3‐dioxane‐4,6‐dione 7(a–e) , respectively, in ethanol medium at RT just within 1 h in excellent yields. The products 3(a–e) were reacted independently with alkylating agents, that is, DMS and DES in the presence of PEG‐600 as an efficient and green solvent, to afford the corresponding N‐substituted methyl and ethyl derivatives 5(a–e) and 7(a–e) , respectively. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:41–48, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20750  相似文献   

7.
Poly(X) (polyriboxanthylic acid) gives up to two differential pulse voltammetric oxidation peaks (peaks I and II) at the PGE. Xanthine, which appears to be a trace contaminant of commercial poly(X) samples, exhibits a differential pulse voltammetric oxidation peak at more negative potentials than the peaks of poly(X). Xanthosine-5'-monophosphate also gives up to two differential pulse voltammetric oxidation peaks at the PGE. An analytical method has been developed to determine trace amounts of xanthine and xanthosine-5'-monophosphate in poly(X) samples based on differential pulse voltammetry.  相似文献   

8.
Abstract— Thermally stimulated luminescence studies of UV- and X-irradiated caffeine have been conducted in the interval77–300 K. The X-ray-induced glow curve exhibits peaks at 102, 128, 158, and 198 K, whereas the UV-induced curve is characterized by peaks with maxima at 120 and 208 K. Analysis of the X-ray-induced glow peaks revealed that the 102 and 128 K peaks obeyed first-order kinetics, while the 158 and 198 K ones followed orders of 1.3 and 1.8, respectively. Trapping parameters associated with the peaks were also elucidated. Concomitant emission spectra of each glow peak (both UV and X-ray induced) were identical and consisted of a band with well-defined maxima at 405 and 480 nm which are attributed to singlet (S1→ S0+ h v ) and triplet (T1→ S0+ h v ) transitions, respectively. At elevated temperatures the triplet transition is not observed due to quenching of the triplet state or to triplet-triplet interactions. An energy-level diagram depicting the thermally stimulated processes in irradiated caffeine is presented.  相似文献   

9.
Two new and ten known alkaloids have been isolated from the bulbs of Lycoris aurea (Amaryllidaceae). The two new compounds, lycosinine A (=[2‐(2,3‐dihydro‐1‐methyl‐1H‐indol‐7‐yl)‐4,5‐dimethoxyphenyl]methanol; 1 ) and lycosinine B (=2‐(2,3‐dihydro‐1‐methyl‐1H‐indol‐7‐yl)‐4,5‐dimethoxybenzaldehyde; 2 ), were fully characterized by spectroscopic methods. In addition, a plausible biogenesis of homolycorine from 1 and 2 is proposed (Scheme).  相似文献   

10.
以复合食品包装袋为实验材料,首次建立了一种用高效液相色谱法(HPLC)同时检测复合食品包装袋中2-(2′-羟基-3′-叔丁基-5′-甲基苯基)-5-氯代苯并三唑(UV-326)和2-(2′-羟基-3′,5′-二叔丁基苯基)-5-氯代苯并三唑(UV-327)含量的分析方法.实验采用超声波辅助提取,提取液旋转蒸发后,经固相...  相似文献   

11.
Benzotriazole UV stabilizers (BUVs) have gained popularity, due to their absorption properties in the near UV range (200–400 nm). They are used in the technology for manufacturing plastics, protective coatings, and cosmetics, to protect against the destructive influence of UV radiation. These compounds are highly resistant to biological and chemical degradation. As a result of insufficient treatment by sewage treatment plants, they accumulate in the environment and in the tissues of living organisms. BUVs have adverse effects on living organisms. This work presents the use of peracetic acid in combination with d-electron metal ions (Fe2+, Co2+), for the chemical oxidation of five UV filters from the benzotriazole group: 2-(2-hydroxy-5-methylphenyl)benzotriazole (UV-P), 2-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl)-4-methylphenol (UV-326), 2,4-di-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl)phenol (UV-327), 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV-328), and 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (UV-329). The oxidation procedure has been optimized based on the design of experiments (DoE) methodology. The oxidation of benzotriazoles follows first order kinetics. The oxidation products of each benzotriazole were investigated, and the oxidation mechanisms of the tested compounds were proposed.  相似文献   

12.
本文采用IR、UV、SEM等实验方法,研究了高分子受阻胺PDS与紫外吸收剂UV-531(2-羟基-4-正辛氧基二苯甲酮)和UV-327(2-(2′-羟基-3′,5′,-二叔丁基)-5氯代苯并三唑)并用对聚丙烯薄膜的光防护作用。实验表明,PDS与UV-531并用有较好的协同效应。这种协同效应被证明主要是PDS对:UV-531的光氧分解有抑制作用所致。PDS与UV-327并用有弱的反协同作用。这种作用被证实是PDS在聚丙烯中的分相作用导致UV-327分散不均所致。实验还发现,PDS对UV-327的光氧分解同样具有抑制作用。并提出了在二种体系中协同与反协同的作用机理。  相似文献   

13.
Characterization of coke on equilibrium, fluid catalytic cracking (FCC) catalysts contaminated with metals was investigated using temperature-programmed oxidation (TPO). TPO spectra of spent equilibrium catalysts from cracking of sour imported heavy gas oil (SIHGO) were deconvoluted into four peaks (Peak K, L, M and N). The four peaks were assigned to different types of coke on the catalyst. Peak L in the TPO spectrum was assigned to the 'contaminant' coke in the vicinity of metals. The amount of contaminant coke (Peak L) correlates with metal-contaminant concentration. The size of Peak L which is related to amount of contaminant coke decreased significantly for the spent highly contaminated catalyst pretreated with hydrogen and methane prior to cracking reactions as compared to the non-pretreated catalysts. Since both hydrogen and methane pretreatment can reduce oxidation state of the vanadium that present at high concentrations on the equilibrium catalysts the decrease in the amount of contaminant-coke represented by Peak L was explained by the reduction of the oxidation state of vanadium. Less contaminant coke was produced after the equilibrium catalysts were pretreated using hydrogen and methane gases since reduced vanadium has lower dehydrogenation activity compared to oxidized vanadium. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

14.
本文采用IR、UV、SEM等实验方法,研究了高分子受阻胺PDS与紫外吸收剂UV-531(2-羟基-4-正辛氧基二苯甲酮)和UV-327(2-(2′-羟基-3′,5′,-二叔丁基)-5氯代苯并三唑)并用对聚 烯薄膜的光防护作用,实验表明,PDS与UV-531并用有较好的协同效应,这种协同效应被证明主要是PDS对UV-531的光氧分解有抑制作用所致。PDS与UV-327并用有弱的反协同作用。这种作用被证实是PDS在聚丙烯中的分相作用导致UV-327分散不均所致,实验还发现,PDS对UV-327的光氧分解同样具有抑制作用。并提出了在二种体系中协同与反协同的作用机理。  相似文献   

15.
研究了MoCl5与n-C7H15COOH间的取代反应条件,如反应温度和时间等,对取代反应产物MoCl5-m(n-C7H15COO)m的影响,讨论了产物的紫外可见光谱,测定了由取代产物组成的铝催化剂对丁二烯聚合反应的活性,结果表明,随着MoCl5中氯的取代量(m=2~4)的增加聚合活性迅速降低。  相似文献   

16.
The reactivity of 3-substituted-6,8-dimethylchromone derivatives 1 - 5 was investigated toward selected nucleophilic reagents namely; 3-amino-1,2,4-triazole, 2-aminobenzimidazole, 7-chloro-4-hydrazinoquinoline, and 5,6-diphenyl-3-hydrazino-1,2,4-triazine. These nucleophiles were allowed to react with 6,8-dimethylchromone-3-carboxaldehyde ( 1 ) through condensation with the aldehyde group with opening of γ-pyrone ring giving compounds 6 , 7 , 10, and 11 . Reactions with 6,8-dimethylchromone-3-carbonitrile ( 2 ), and 6,8-dimethylchromone-3-carboxylic acid ( 3 ) occur via attack at position 2 in both compounds followed by cycloaddition onto the nitrile function (in case of carbonitrile 2 ) or decarboxylation and cyclocondensation with the carbonyl group (in case of carboxylic acid 3 ). The current nucleophilic reagents reacted with simple condensation products 4 and 5 , in boiling dioxane, through nucleophilic addition at the exocyclic vinyl bond followed by addition at the CN group giving 6,8-dimethylchromone linked various heterocyclic systems 20 - 27 .  相似文献   

17.
本文用IR、UV、ESR、TLC等方法研究了新型的双功能受阻胺光稳定剂,Tinuvin-144 [2-(4′-羟基-3′,5′-二叔丁基)苄基-2-正丁基丙二酸五甲基哌啶醇酯]与紫外线吸收剂,UV-531(2-羟基-4-正辛氧基二苯甲酮)和UV-327(2-[2′-羟基-3′,5′-二叔丁基]-5-氯 代苯并三唑)并用体系对聚丙烯光稳定化的并用效应。结果表明,Tinuvin-144与UV-531,UV-327并用时均具有良好的协同效应,144对531,327或531,327对144的光分解均具有相互的保护作用。结果还表明,144与531或327无论在模拟体系或聚丙烯中,在诱导期内均不存在促使他们消耗的化学反应,提出了协同作用的机理。  相似文献   

18.
2‐(2‐(1‐(1H‐Indol‐3‐yl)ethylidene)‐hydrazinyl)‐4‐substituted 5‐(aryldiazenyl)thiazoles and 5‐((1‐(1H‐indol‐3‐yl)ethylidene)hydrazono)‐2‐substituted‐4‐phenyl‐4,5‐dihydro‐1,3,4‐thiadiazoles were synthesized via reaction of hydrazonoyl halides and 2‐(1‐(1H‐indol‐3‐yl)ethylidene)hydrazine‐1‐carbothioamide and alkyl 2‐(1‐(1H‐indol‐3‐yl)ethylidene)hydrazine‐1‐carbodithioate in ethanolic triethylamine. Structures of the newly synthesis were elucidated on the basis of elemental analysis, spectral data, and alternative synthetic route whenever possible.  相似文献   

19.
Peptide mass fingerprinting (PMF) is a powerful tool for identification of proteins separated by two-dimensional electrophoresis (2-DE). With the increase in sensitivity of peptide mass determination it becomes obvious that even spots looking well separated on a 2-DE gel may consist of several proteins. As a result the number of mass peaks in PMFs increased dramatically leaving many unassigned after a first database search. A number of these are caused by experiment-specific contaminants or by neighbor spots, as well as by additional proteins or post-translational modifications. To understand the complete protein composition of a spot we suggest an iterative procedure based on large numbers of PMFs, exemplified by PMFs of 480 Helicobacter pylori protein spots. Three key iterations were applied: (1) Elimination of contaminant mass peaks determined by MS-Screener (a software developed for this purpose) followed by reanalysis; (2) neighbor spot mass peak determination by cluster analysis, elimination from the peak list and repeated search; (3) re-evaluation of contaminant peaks. The quality of the identification was improved and spots previously unidentified were assigned to proteins. Eight additional spots were identified with this procedure, increasing the total number of identified spots to 455.  相似文献   

20.
The reaction of 1H‐indol‐2,3‐diones with 1,6‐dibromohexane has resulted in the formation of new 1H‐indol‐2,3‐diones‐1,1′‐(1,6‐hexanediyl)bis in quantitative yields. These compounds have been used for the synthesis of novel [3′‐(2,3‐dimethyl‐5‐oxo‐1‐phenyl‐3‐pyrazolin‐4‐yl)spiro[3H‐indol‐3,2′‐thiazolidine]‐2,4′‐dione]‐1,1′‐(1,6‐hexanediyl)bis via bis Schiff's bases, [3‐(2,3‐dimethyl‐5‐oxo‐1‐phenyl‐3‐pyrazolin‐4‐yl) imino‐1H‐indol‐2‐one]‐1,1′‐(1,6‐hexanediyl)bis.  相似文献   

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