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1.
戈早川  周建明 《分析化学》2004,32(1):99-101
以2%CPC-醋酸乙酯(9:1)胶束溶液为展开剂,在聚酰胺薄膜上成功地分离了小檗碱、巴马汀和药根碱。以345nm为测定波长,550nm为参比波长进行扫描测定,建立了一种新的同时测定黄连及其制剂中小檗碱、巴马汀和药根碱的胶束薄层扫描法。小檗碱、巴马汀和药根碱的线性范围分别为0.2—2.4、0.1—1.0和0.1—1.0μg;回收率分别为97.7%-99.4%、101.7%~102.6%和96.7%-97.8%;相对标准偏差分别为1.4%-1.7%、1.9%-2.7%和1.8%-2.2%。  相似文献   

2.
核级银铟镉合金中Ag In Cd 的连续滴定   总被引:1,自引:0,他引:1  
刘英  张文  童坚 《分析试验室》1999,18(6):67-70
研究了测定核级银铟镉合金中Ag、In、Cd的连续滴定法。以电位滴定法测定Ag;在pH2.5以EDTA滴定In;在pH≥5.5以EDTA滴定Cd,当n=11时,其RSD分别为:Ag0.11%、In0.52%、Cd1.1%,合成试样分析回收率分别为:Ag99.8%~100.1%、In99.6%~100.3%、Co97.6%~101.3%,测定92个合金试样,其Ag,In,Cd合量范围为:99.78%~  相似文献   

3.
酵素菌肥的金属元素营养分析   总被引:1,自引:0,他引:1  
在磷酸根、硅酸根存在下以2%硝酸镧作机体改进剂,测定了酵素菌肥中多种金属元素的含量,各元素的平均回收率分别为:K98.69%,Ca100.37%,Mg97.81%,Na96.06%,Cu98.26%,Fe96.45%,Zn99.78%,Sr93.54%,Li94.22%。方法简便,快速可靠,肯定 酵素菌肥的金属元素营养价值。  相似文献   

4.
火焰原子吸收光谱法测定尘铅前处理方法的研究   总被引:1,自引:0,他引:1  
采用火焰原子吸收光谱法测定尘铅样品,在0-1.00mg/L范围内样品中铅含量与吸光度呈良好线性关系,检出限为2.88μg/m^2(按定容体积50mL、采样体积400L计)。采取酸煮法、索氏提取法、微波消解法、超声波提取法等4种前处理方法,在0.100,0.500,1.00mg3个质量水平对空白滤筒进行加标回收试验,4种前处理方法的回收率和测定结果的相对标准偏差分别为91.8%-97.4%,2.2%~3.2%;83.0%-86.8%,7.4%-10.3%;93.6%-97.2%,2.5%~3.7%;89.3%-90.9%,3.2%~4.5%,提取效果以酸煮法和微波消解法最佳,超声波提取法次之,索氏提取法最差。  相似文献   

5.
应用双波长分光光度法测定阿丙沙星可溶性粉中阿莫西林、盐酸环丙沙星的含量。以pH=5.0的磷酸盐缓冲液为溶剂,在波长229、248、315、400nm处进行测定,阿莫西林的浓度在5.130~25.650μg/mL、盐酸环丙沙星的浓度在4.888~24.440μg/mL范围内分别与其吸光度差值呈良好的线性关系。阿莫西林的回收率为99.30%~100.19%,测定结果的相对标准偏差为0.60%~1.00%(n=5),盐酸环丙沙星的回收率为99.30%~99.86%,测定结果的相对标准偏差为0.84%~1.02%(n=5)。  相似文献   

6.
毛细管气相色谱法对大麻中主要成分的定性定量分析   总被引:6,自引:0,他引:6  
彭兴盛 《色谱》1998,16(2):170-172
采用毛细管气相色谱法测定大麻中大麻酚、四氢大麻酚和大麻二酚的含量。以氯仿为提取溶剂,甲醇为色谱溶剂,用HP-5(10m×0.53mm×2.65μm)柱,以柱温220℃进行测定。大麻二酚、四氢大麻酚和大麻酚在20~120mg/L的浓度范围内线性关系良好,r分别为0.9994,0.9991和0.9995,回收率分别为97.3%~104.0%,97.3%~106.6%和95.3%~102.4%,最低检测限均为0.2μg/mL。利用3种主要成分保留时间的良好重现性也可进行定性。方法简便、快速、准确、灵敏。  相似文献   

7.
以恒电流库仑分析法测定维生素C、安乃近、二巯丙醇等药物的含量,以永停终,最法指示库仑滴定终点,方法简便快速,相对误差为0.21%~0.28%,相对标准偏差(n=11)为0.027%~0.034%。  相似文献   

8.
水果、蔬菜中16种有机氯残留农药的毛细管气相色谱测定法   总被引:18,自引:1,他引:17  
采用柱层析净化方式,以HP-101弹性石英毛细管柱为分离柱,电子捕获检测的气相色谱法测定水果、蔬菜中16种有机氯农药残留量。方法的检出限为0.1×10-9~2.0×10-9,回收率范围在87.5%~106.3%之间,相对标准偏差为3.0%~9.5%。  相似文献   

9.
马齿苋及其籽中脂肪酸的比较研究   总被引:15,自引:1,他引:15  
本实验利用GC-MS分析技术对马齿苋全草及其籽中的脂肪酸(以甲酯的形式)进行了分析,共鉴定出8种脂肪酸。全草中以亚麻酸(47.16%)、亚油酸(22.00%)及棕榈酸(17.4%)为主,籽中以亚油酸(45.86%)及亚麻酸(30.61%)为主。  相似文献   

10.
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   

11.
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   

12.
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   

13.
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   

14.
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   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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