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1.
除草剂双苯唑快的反相高效液相色谱法分析   总被引:1,自引:0,他引:1  
王以燕  宗伏霖 《色谱》1999,17(1):83-84
采用反相高效液相色谱法分析除草剂——双苯唑快,色谱柱为Selectosil5C18不锈钢柱,检测波长为254nm,用V(甲醇)V(水)=6040(pH3)为流动相。方法的变异系数为0.41%,平均回收率为99.34%,线性相关系数为0.9999。方法快速、准确。  相似文献   

2.
高效液相色谱法测定皮炎宁酊中间苯二酚和水杨酸的含量   总被引:16,自引:0,他引:16  
郭兴杰  周密 《色谱》1998,16(6):532-533
采用高效液相色谱法测定了皮炎宁酊中间苯二酚和水杨酸的含量。色谱柱为HypersilODS柱,流动相为V(甲醇)∶V(水)∶V(乙酸)=50∶50∶0.9。检测波长为285nm。在此条件下,间苯二酚和水杨酸可与其降解产物及杂质完全分开。  相似文献   

3.
山药中尿囊素的高效液相色谱分析方法研究   总被引:8,自引:1,他引:8  
周心如  曹京宜 《色谱》1996,14(2):129-131
建立了山药中尿囊素的高效液相色谱分析方法。样品用甲醇-水(90:10,V/V)提取,在氨基柱上进行高效液相色谱分析,紫外检测波长224nm,流动相为甲醇-水(80:20,V/V),相对标准偏差为2.0%(n=5),尿囊素的回收率为98.8%(n=4)。  相似文献   

4.
谢航  张声华 《色谱》1997,15(1):54-56
干枸杞经粉碎、匀浆、离心后,通过阳离子交换柱脱去样品中其它氨基酸,再通过Zorbax-C8柱进行柱前衍生分离。衍生剂:A.4%OPA甲醇溶液;B.尿素∶磷酸钠盐缓冲液(pH6.8)=1∶3(W/V)。流动相:甲醇∶0.01mol/L乙酸钠溶液(pH6.8)=35∶65(V/V)。紫外检测波长330nm。牛磺酸浓度在0.1~1.0mmol/L范围内可被定量测定。回收率可达100.31%±1.98%,变异系数(CV)为1.94%。  相似文献   

5.
反相高效液相色谱法测定化妆品中的防晒剂   总被引:7,自引:0,他引:7  
姚孝元  郑星泉  秦效英  戚其平 《色谱》1998,16(3):223-225
用反相高效液相色谱法在20min内同时测定化妆品中11种防晒剂。色谱柱为YWG-C18柱,流动相为甲醇-四氢呋喃-水-高氯酸(2002001600.1,V/V),检测波长为311nm。报告了对103种防晒化妆品测定的结果。  相似文献   

6.
高效液相色谱法测定饲料中的喹乙醇   总被引:3,自引:0,他引:3  
李来生  邱水平 《色谱》1997,15(5):440-441
报道饲料中喹乙醇的高效液相色谱分析方法。以乙酰苯胺为内标,样品用二甲替甲酰胺(DMF)提取,在C8柱上进行色谱分析,紫外检测波长260nm,流动相为甲醇-水(2080,V/V),喹乙醇的回收率为98.58%~101.63%,相对标准偏差为2.67%~4.25%。  相似文献   

7.
液相色谱法测定生物发酵液中水溶性维生素的研究   总被引:6,自引:0,他引:6  
本文采用反相离子对色谱测定了生物发酵液中的七种水溶性维生素。提出了用自行装填的酸性氧化铝(0.19~0.15mm)前置柱,和5%乙酸洗脱样品的前处理方法;并就有关的色谱条件进行了选择。色谱柱为NovaPakC18;流动相A液为0.05mol/L庚烷磺酸盐(PICB7),冰乙酸调pH=2.5;B液为甲醇+三乙胺(100+0.5);梯度洗脱;UV254nm、290nm、360nm同时测定。线性范围为0.1~10μg,各种维生素的RSD在1.2%~3.0%之间(VitaminB12除外),回收率大于90%。  相似文献   

8.
以邻苯二甲醛及3-巯基丙酸为衍生试剂,50mmol/L磷酸缓冲液(pH7.0)-乙腈(94∶6,V/V)为流动相,在LichrosorbRP18(150mm×4.6mmi.d.,5μm)柱上,研究并建立了测定动物肠粘膜中谷氨酰胺(Gln)的柱前衍生荧光RP-HPLC法。样品与衍生剂按4∶1进行衍生反应,Ex=230nm,Em=389nm;流速为2.0mL/min。Gln的保留时间为3.158min,检测限为25μmol/L(S/N=3.5),线性范围为50~3200μmol/L,r=0.9996。  相似文献   

9.
高效液相色谱法测定血清中茶碱浓度   总被引:2,自引:0,他引:2  
采用高效液相色谱,分析柱:3μm,3.3cm*4.6mm,I.D(Perkin Elmer,USA);预柱:10μm,1cm*2.1mm,I.D(Perkin ELmer,USA);以乙酰氨基酚为内标对氯仿-异丙醇(95:5,V/V)提取样品进行了分析,流动相:0.1mol/L醋酸缓冲液(PH=4.5)-甲醇(70:30,V/V);检测波长:270nm;流速0.5mL/min,3min即完成一次茶  相似文献   

10.
用HPLC测定具有改善睡眠等特定功能的保健药品“梦通宁”中的褪黑激素,并结合紫外光谱来鉴定样品中的褪黑激素。以Novapak C18柱为分离柱,V(甲醇):V(0.05mol/L的Na2HPO4)=30:70作流动相,检测波长为230nm,用外标法进行定量分析,方法回收率98,11%,检出限为0.5mg/L。  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.
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   

14.
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   

15.
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   

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.
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.
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   

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.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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