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1.
提出了高效液相色谱法测定水中痕量甲磺隆。水样经Oasis MCX固相萃取小柱富集并净化后,以Extend C18柱(250 mm×4.6 mm,5μm)为固定相,0.2 mol.L-1甲酸-甲醇-乙腈(60+20+20)混合溶液为流动相进行分离,在225 nm波长处,用二极管阵列检测器测定。甲磺隆浓度在0.005~5.0 mg.L-1范围内与其峰面积呈线性关系,测定下限(10S/N)为0.005 mg.L-1。方法用于水样分析,加标回收率在94.0%~102.0%之间,相对标准偏差(n=6)小于6.5%。  相似文献   

2.
采用分子印迹-基质固相分散-高效液相色谱法(MI-MSPD-HPLC)测定血液中痕量苯磺酸氨氯地平。制备苯磺酸氨氯地平分子印迹聚合物,以此为基质固相分散剂与样品混合均匀,风干后装柱,用甲醇洗脱苯磺酸氨氯地平。洗脱液在Inertsil DOS-SP分离柱上分离,以甲醇-乙腈-水(70+22+8)混合液为流动相进行洗脱,检测波长为237nm。氨氯地平的线性范围为1.7~20.0μg·L-1,检出限(3S/N)为0.5μg·L-1,测定下限(10S/N)为1.7μg·L-1。对空白血液样品进行加标回收试验,回收率在91.0%~109%之间,测定值的相对标准偏差(n=5)在3.7%~4.8%之间。方法可用于测定血液中的苯磺酸氨氯地平。  相似文献   

3.
采用磁固相萃取-高效液相色谱法测定环境水样中双酚A的含量。优化的试验条件如下:1 50mL水样中加入20mg磁性微球进行萃取;2水样的pH为3.0;3萃取时间为15min;4解析溶剂为甲醇(80+20)溶液;5解析时间为10 min。采用C18色谱柱为分离柱,以甲醇-水(85+15)混合液为流动相,在检测波长224nm处进行测定。双酚A的质量浓度在5.0~500μg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)为1.0μg·L-1。方法应用于环境水样的分析,加标回收率在81.4%~109%之间,测定值的相对标准偏差(n=6)在5.7%~8.6%之间。  相似文献   

4.
采用固相萃取-超高效液相色谱法测定水体中呋喃西林、呋喃它酮、呋喃妥因、呋喃唑酮等4种硝基呋喃类药物的含量。样品经HLB固相萃取柱净化后,用氨水-甲醇(5+95)溶液洗脱。以BEH C18色谱柱为分离柱,以乙腈和含有0.1%(体积分数)甲酸的2mmol·L-1乙酸铵溶液以体积比23比77组成的混合液为流动相,在检测波长360nm处进行测定。4种硝基呋喃类药物的质量浓度均在5.0~200μg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)为0.02μg·L-1。以空白样品为基体进行加标回收试验,所得回收率在84.5%~97.2%之间,测定值的相对标准偏差(n=6)在1.5%~4.5%之间。  相似文献   

5.
采用固相萃取-高效液相色谱-原子荧光光谱法联用技术测定了水样中无机汞及有机汞。水样流经以DDTC溶液改性的C18固相萃取小柱。用含有10%(体积分数)乙腈的混合洗脱液4mL,分4次,以1~2mL·min-1流量从小柱上将3种形态的汞洗脱。收集洗脱液,混匀,过滤后通过Venusil MP C18色谱柱,用乙腈、145mmol·L-1乙酸铵溶液和20mmol·L-1半胱氨酸溶液(5+45+50)混合液作为流动相进行色谱分离。根据选定的形态分析条件,用原子荧光光谱法进行测定。汞质量浓度在0.5~20μg·L-1范围内与其峰面积呈线性关系,汞(Ⅱ)、甲基汞、乙基汞的检出限(3S/N)依次为1.6,0.5,1.2ng·L-1。加标回收率在71.2%~95.2%之间,测定值的相对标准偏差(n=6)在4.9%~10%之间。  相似文献   

6.
采用固相萃取-气相色谱法测定鱼塘投毒案件水样中硫丹的含量。取自鱼塘的水样调至pH 4,经CNWBOND LC-C18固相萃取柱分离,用三氯甲烷作为洗脱溶剂,所得提取液用CP-SIL8毛细管色谱柱分离,电子捕获检测器检测。α-硫丹和β-硫丹的峰面积与其质量浓度在0.05~5μg·L-1相同的范围内呈线性关系,方法的检出限(3S/N)均为0.01μg·L-1。加标回收率在91.1%~95.8%之间,测定值的相对标准偏差(n=6)小于1%。  相似文献   

7.
结合固相萃取与高效液相色谱分析技术,建立了一种可以同时检测环境水体中10种微量药品和个人护理用品(PPCPs)的分析方法。将水样pH调节至5,过Poly-Sery HLB固相萃取小柱,用6mL的甲醇洗脱。洗脱液在Agilent Eclipse XDB-C18色谱柱上分离,以水-乙腈为流动相进行梯度洗脱,检测波长为224nm。10种目标化合物的质量浓度在0.5~20mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)为6.0~54.6μg·L-1,测定下限(10S/N)为20.1~182.1μg·L-1。对自来水和地表水进行加标试验,回收率分别在71.2%~108%和56.7%~97.6%之间。方法用于某城镇污水处理厂的原水和最终处理出水的检测。  相似文献   

8.
建立了超高效液相色谱-串联质谱法测定玉米中硝磺草酮及其代谢物(MNBA)的残留分析方法。样品用乙腈-水溶液提取,取适量提取液用甲酸酸化至pH 2,过HLB固相萃取柱进行净化,用甲醇-乙醚(70∶30,V/V)洗脱,洗脱液用氮气吹至近干,用1 mmol/L醋酸铵-乙腈(25∶75,V/V)定容后进行质谱分析,利用基质校正曲线对其准确定量。硝磺草酮和MNBA在1~200μg/L浓度范围内呈线性关系,相关系数均大于0.99,在添加浓度5~50μg/kg范围内,硝磺草酮及其代谢物MNBA的平均回收率为83.8%~101.1%,相对标准偏差在5.3%~12.8%之间,硝磺草酮和代谢物MNBA定量限分别为1.0和2.0μg/kg。  相似文献   

9.
采用高效液相色谱-四极杆飞行时间质谱(HPLC/QTOF-MS)对酮苯丙氨酸钙原料药中的有关物质进行鉴定,并采用反相高效液相色谱法(RP/HPLC)测定有关物质的含量。有关物质含量测定采用C18色谱柱(4.6 mm×150 mm,5μm),20 mmol·L-1磷酸二氢钾(磷酸调至p H 3.3)-乙腈(85∶15)为流动相等度洗脱,流速1 m L·min-1,检测波长205 nm,柱温30℃,进样量10μL。结果确证了2个有关物质分别为苯甲酸和苯乙酸。在优化的色谱条件下,苯甲酸和苯乙酸分别在0.64~5.76μg·m L-1(r=0.999 6)和0.65~5.82μg·m L-1(r=0.999 5)范围内线性关系良好,检出限分别为1.3 ng和1.6 ng,平均回收率(n=9)分别为99.6%和99.0%,相对标准偏差分别为1.6%和1.5%。结果表明,HPLC/QTOF-MS可以快速鉴定酮苯丙氨酸钙中的有关物质。本方法灵敏度高、重现性好、准确可靠,可用于酮苯丙氨酸钙原料药有关物质的检测分析及质量控制。  相似文献   

10.
建立了测定对虾血淋巴、肌肉和肝胰腺等组织中噁喹酸含量的反相高效液相色谱法。采用乙腈提取对虾血淋巴、肌肉、肝胰腺和鳃组织中噁喹酸,色谱柱为Aglient Zorbax SB-C18柱(150×4.6mm,5μm),以乙腈-0.01mol·L-1四丁基溴化铵(磷酸调节pH为2.75)为流动相,流速1.0mL·min-1,荧光检测器检测。噁喹酸在0.002~10μg·mL-1范围内线性关系良好,相关系数R2=0.9996~0.9999。加标回收率为84.70%~90.60%,日内、日间精密度(RSD)分别为1.60%~4.02%、2.91%~4.73%,定量限分别为0.02μg·mL-1、0.01μg·g-1、0.02μg·g-1和0.02μg·g-1。该方法操作简单,重现性好,适用于对虾样品中噁喹酸含量的分析。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

16.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

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20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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