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1.
建立毛细管气相色谱同时测定盐酸氨溴索原料药中甲醇、丙酮两种有机溶刺残留量的方法。两种残留有机溶剂在DB-624毛细管气相色谱柱上均达到良好分离。甲醇和丙酮的线性范围分别为32.54~325.4μg/mL(r=0.9998)、40.68—406.8μg/mL(r=0.9995),回收率分别为94.7%~101.1%、93.9%~99.1%,检出限分别小于20、10μg/mL,测定结果的相对标准偏差均不大于3.6%(n=5)。  相似文献   

2.
抑制型离子色谱法测定白酒中的F-、Cl-、NO2-、H2 PO4-、NO3-   总被引:3,自引:0,他引:3  
用抑制型离子色谱法测定白酒中的F^-、Cl^-、NO2^-、H2PO4^-、NO3^-。流动相为4mmol/LNa2CO3—3 mmol/LNaHCO3混合溶液,流速为1.5mL/min,进样量为0、5mL,在最佳色谱条件下,5种无机阴离子10min内实现基线分离。F^-、Cl^-、NO2^-、H2PO4^_、NO3^-的检出限分别为0、008、0.012、0、030、0.068、0.077mg/L。测定结果的相对标准偏差分别为1.86%、1.30%、2.06%、1.82%、1.50%,回收率分别为108.0%、94.0%、101.0%、98.7%、94.4%。  相似文献   

3.
以N,N-二甲基甲酰胺(DMF)为溶剂,丁酮为内标,采用PV-101毛细管色谱柱 (30 m×0.22 mm),氢火焰离子化检测器,建立兰索拉唑中五种有机溶剂甲醇、乙醇、丙酮、二氯甲烷、乙酸乙酯残留量的定量分析方法。五种有机溶剂检出限分别为0.002 4%,0.002 4%, 0.001 2%,0.000 6%,0.000 6%;在10-1000 mg·L-1浓度范围内,各组分线性关系良好;对应的平均回收率分别为100.8%±3.6%,102.1%±2.3%,99.97%±4.1%,99.63%±2.7%, 102.3%±3.5%。  相似文献   

4.
双氯乙酸苯二酚酯的合成   总被引:2,自引:0,他引:2  
以丙酮为溶剂、三乙胺为缚酸剂,苯二酚10mmol,n(苯二酚):n(氯乙酰氯)=1.0:3.0,在0℃~5℃的冰水浴下反应30min后再加热回流4h~5h,合成了两个双氯乙酸苯二酚酯(收率分别为63.4%,70.2%),其结构经元素分析、1H NMR和MS确认。  相似文献   

5.
高效液相色谱法测定山生柳中酚苷类成分的含量   总被引:2,自引:0,他引:2  
用高效液相色谱法测定山生柳中水杨苷、水杨酰水杨苷和木犀草素07-O-葡萄糖苷的含量,流动相为1.5%醋酸溶液-甲醇,Symmetry C18柱,柱温30℃,流速1.1mL/min,检测波长270nm,线性浓度范围分别为527.0-105.4um/mL,140-28.0ug/mL,81.0-16.2ug/mL,平均回收率是104.9%和103.6%,RSD分别为2.0%,0.3%和0.3%。  相似文献   

6.
超临界流体萃取气相色谱法测定鱼肉中的毒死蜱残留   总被引:23,自引:0,他引:23  
建立了利用离线超临界CO2萃取气相色谱(SFE-GC)测定鱼肌肉中毒死蜱残留量的分析方法。超临界CO2萃取鱼肌肉中毒死蜱的适宜条件为:温度100℃,压力41.370MPa,CO2流量为1mL/min,动态萃取30min,静态萃取时间15min,调节剂甲醇(添加量0.5mL),收集液丙酮。最小检出量为0.01ng;添加回收率为77.3%~105.1%;相对标准偏差(RSD)为2.4%~15.4%,符合残留分析要求。全程分析时间小于2h。  相似文献   

7.
高效液相色谱-电感耦合等离子体质谱法测定汞的3种形态   总被引:7,自引:0,他引:7  
利用HPLC—ICP—MS联用技术对Hg的3种不同形态(甲基汞、乙基汞、Hg^2+)进行分析,通过条件优化,确定了最佳分离条件:流动相为超纯水并含有5%甲醇、0.06mol/L乙酰胺和0.1% 2-巯基乙醇、进样量1000μL、流速0.4mL/min、pH=6.8,最佳检测条件是:RF功率1550W、积分时间0.3s、采样深度:4.5mm、载气流速0.75L/min、辅助气流速0.40L/min。在此条件下,3种形态汞的检出限达到0.1ng/L,检出限降低两个数量级;同时对模拟海水样品中3种形态微量的汞进行测定,加标回收率在90%-110%之间。说明该方法可应用于微含量环境样品的分析。  相似文献   

8.
铅形态的高效液相色谱-电感耦合等离子体质谱分析   总被引:3,自引:0,他引:3  
潘元海  刘湘生  何小青  王长华 《分析化学》2005,33(11):1560-1564
用50mm的反相高效液相色谱短柱在V甲醇/VH2O=55/45,其中水相为0.1mol/L乙酸0.1mol/L乙酸铵的缓冲溶液(pH=4.70),流速0.6mL/min条件下,约10min内实现了无机铅离子(Pb^2+)、氯化三甲基铅(TML)、氯化三乙基铅(TEL)和氯化三苯基铅(TPhL)的高效液相色谱.电感耦合等离子体质谱(HPLC-ICP-MS)联用分析。4种铅形态在去离子水和自来水中的加标回收率分别为93.8%-115.6%和89.3%-137.8%;峰强度和保留时间的RSD分别为7.4%-14.3%和0.5%-1.3%;仪器检出限及方法检出限分别为0.27-3.07μg/L和1.20-2.33μg/L。  相似文献   

9.
加速溶剂萃取-气相色谱法测定土壤中的有机磷农药残留   总被引:30,自引:0,他引:30  
采用加速溶剂萃取法测定土壤中有机磷农药残留物。土壤样品与无水硫酸钠(1:2m/m)混合后,再加适量中性氧化铝和活性碳,用丙酮、甲醇(1:1,V/V)在加速溶剂萃取仪上以10.3Mpa、60℃提取10min,对土壤中10种有机磷农药的回收率在80.4%-113.7%之间。该法用于土壤中的有机磷农药残留测定,速度快,检出限为0.01—0.06μg/kg。  相似文献   

10.
李克昌  张恒彬  刘佳  曹学静  张玉敏 《分析化学》2005,33(11):1580-1582
建立了以磷酸氢二钾-磷酸盐缓冲溶液中添加甲醇为流动相,以反相高效液相色谱同时测定吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的新方法。在流动相为甲醇-0.1mol/L磷酸氢二钾和磷酸缓冲溶液、pH为6.0的最佳条件下,吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的加标回收率分别为98.2%~102.1%、99.1%~101.3%、97.8%~100.7%和99.1%~102.4%;线性范围分别为20~980、18~913、19~943和18~902mg/L;检出限分别为2.0、1.8、1.9和1.8mg/L。本法可同时测定电氧化2一甲基吡啶过程中电解液。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
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   

13.
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   

14.
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   

15.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

16.
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   

17.
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   

18.
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   

19.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

20.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

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