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1.
基于溶解沉淀-气相色谱-质谱联用技术,建立了一种同时测定PC塑料粒子中十八烷基3-(3,5-二叔丁基-4-羟苯基)丙酸酯(抗氧剂1076)和三[2,4-二叔丁基苯基]亚磷酸酯(抗氧剂168)含量的方法。通过研究不同沉淀剂对抗氧剂提取率的影响,确定了最优沉淀剂。处理后的上清液采用HP-5 MS分离,选择离子模式检测,外标法定量。在优化实验条件下,抗氧剂1076在2~50 mg/L、抗氧剂168在0.1~50 mg/L质量浓度范围内相关系数(r2)均大于0.99,抗氧剂1076和抗氧剂168的方法检出限(LOD)分别为50 mg/kg和0.75 mg/kg,定量限(LOQ)分别为166.7 mg/kg和2.5 mg/kg,回收率为80.3%~119.8%,相对标准偏差(RSDs,n=6)为5.8%~9.2%。该方法适用于PC塑料粒子中抗氧剂1076和抗氧剂168含量的测定。  相似文献   

2.
反相高效液相色谱-质谱法测定喷气燃料中抗氧剂含量   总被引:1,自引:0,他引:1  
薛艳  袁汉成  赵贵平 《色谱》2004,22(6):661-661
分析喷气燃料中抗氧剂的真实含量对于研究和控制喷气燃料贮存的安全性具有重要意义。国外Cunningham等[1]用高效液相色谱 紫外检测器分析抗氧剂,国内目前普遍采用正相色谱,即以正己烷为流动相、用硅胶色谱柱和紫外检测器,直接测定喷气燃料中抗氧剂2,6 二叔丁基对甲酚的含量  相似文献   

3.
赵秋雯  范国梁  周维义  金秀杰 《色谱》1995,13(3):195-199
 用高效液相制备色谱法分离、提纯抗氧剂1010加成反应中产生的副产物。并用红外光谱等定性方法确定提纯物结构。  相似文献   

4.
反相高效液相色谱测定抗氧剂3114   总被引:2,自引:0,他引:2  
建立了用反相高效液相色谱测定抗氧剂3114的方法。优化了试验条件,采用μ-BondapakC18为固定相,甲醇作为流动相,选择270nm作为检测波长,外标法定量,可在8min内完成测定任务。  相似文献   

5.
建立了超高效液相色谱-串联质谱(UPLC-MS/MS)测定药用胶塞中12种抗氧剂的分析方法。胶塞以20%乙醇为提取溶剂,60 ℃浸泡72 h,提取液经乙腈辅助盐析液液萃取后过0.22 μm 聚四氟乙烯(PTFE)滤膜,以甲醇-水(含0.02%甲酸和5 mmol/L甲酸铵)为流动相进行梯度洗脱,经Hypersil Gold C8(100 mm × 2.1 mm,1.9 μm)色谱柱分离,电喷雾离子源(ESI)正、负离子切换模式下以多反应监测(MRM)模式扫描,外标法定量。结果表明,在最优条件下,12种抗氧剂线性关系良好,相关系数(r2)均大于0.995,检出限(LOD)和定量下限(LOQ)分别为0.10~25 ng/g和0.25~75 ng/g,平均加标回收率为75.6%~117%,相对标准偏差(RSD,n = 6)为0.90%~8.4%。该方法前处理简单、准确度高、检出限低,分析时间短至6 min,可用于药用胶塞中12种抗氧剂的快速筛查。  相似文献   

6.
高效液相色谱/大气压化学电离质谱分析新型复合抗氧剂   总被引:4,自引:0,他引:4  
祝玉杰  付兴国  陈立仁 《色谱》2001,19(4):335-337
 应用高效液相色谱 /大气压化学电离质谱技术 ,其中包括直接进样技术、同时正负离子扫描方式、可编程的源内碰撞诱导解离 (CID)技术 ,以及红外光谱分析技术 ,对一种用于润滑油的新型复合抗氧剂进行了分离分析 ,并对其中的有效组分进行了定性鉴定。该方法简便、快速、可靠。  相似文献   

7.
建立了高纯度苯肼的高效液相色谱测定方法。在流动相中加入抗氧剂和色谱改性剂(M),很好解决了苯肼色谱峰拖尾问题,可准确测定高纯苯肼中杂质含量。优化条件是:Agilent hc-C18色谱柱(150×4.6mm,5μm);流动相为甲醇-水(体积比40∶60)其中所含抗氧剂、色谱改性剂(M)、K2HPO4-KH2PO4浓度均为0.02mol/L;流速1.0mL/min;进样量20μL;检测波长272nm。高纯苯肼中所含杂质苯胺、苯酚以及联苯胺,在5~120μg/mL范围内均具有良好的线性关系,相关系数r>0.9993。  相似文献   

8.
报道了一种检测油脂中的合成抗氧剂(BHT、BHA、TBHQ和PG)MLC方法,含有抗氧剂的油脂按1∶4(Voil:V2-propanol)被稀释、过滤,并且在没有前期萃取的情况下直接注射进样分析。研究了抗氧剂的MLC方法的检测条件。当C18色谱柱、胶束流动相中含0.08MSDS,5%(V/V)异丙醇和0.01mol/LNaH2PO4.H2O,胶束流动相的pH为3~4,检测波长为280nm,流速1ml/min时,在1~15μg/g的范围内标准曲线呈线性关系(r0.9992),4种抗氧剂的检测限为0.1~0.4μg/g。方法回收率为89.1%~99.9%。  相似文献   

9.
郑荣  许勇  于建  王柯 《分析试验室》2014,(7):864-868
建立了乳液、霜、水以及油类化妆品中25种邻苯二甲酸酯类化合物的气相色谱-质谱和液相色谱-质谱测定方法。不同基质样品经不同方法净化处理后,采用气相色谱-质谱或液相色谱-质谱进行测定。气相色谱-质谱法采用DB-5MS毛细管色谱柱(30 m,250 mm×0.25μm),程序升温,选择离子模式同时测定21种邻苯二甲酸酯类化合物。液相色谱-质谱采用MN EC-C18色谱柱(4.6×100 mm,2.7μm),以甲醇和0.1%甲酸为流动相,梯度洗脱,流速0.7 mL/min,采用电喷雾电离(ESI+),多反应监测(MRM)模式同时测定24种邻苯二甲酸酯类化合物。25种邻苯二甲酸酯类化合物的线性关系良好,相关系数均大于0.999,回收率实验结果为89.3%~105.6%,RSD为0.4%~4.0%,检出限均小于0.3 mg/kg。方法适用于化妆品中邻苯二甲酸酯类化合物的全面筛查。  相似文献   

10.
采用HPLC-UV法对聚丙烯(PP)中抗氧剂1010和168以及成核剂NA11三种添加剂同时进行快速定性、定量分析.通过对现有的索氏提取器进行改进,提高了萃取效率;通过优化洗脱条件,确保了三个色谱峰的完全分离,三种添加剂标准曲线相关系数分别为0.9979,0.9975和0.9975.建立了上述三种添加剂在PP中剩余量测试值与实际工艺添加量的关系曲线,并用这些关系曲线结合对剩余添加剂的定量分析结果确定某种PP产品中这三种添加剂的实际工艺添加量.研究结果表明:上述关系曲线的相关系数(r)均大于0.95,采用本文方法确定的某种PP产品中抗氧剂1010、抗氧剂168和成核剂NA11的工艺添加量与实际工艺添加量之间的相对误差分别为-5.46%,-3.00%和-4.27%.  相似文献   

11.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

14.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

15.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

16.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

17.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

18.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

19.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

20.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

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