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1.
研究了盐酸吖啶黄与脱氧核糖核酸(DNA)之间的共振瑞利散射(RRS)增强作用,提出了共振瑞利散射技术测定核酸的方法。在pH 6.4的B-R缓冲溶液中,盐酸吖啶黄与脱氧核糖核酸结合使溶液共振瑞利散射强度增强,其最大散射峰位于505 nm处,而在330 nm波长处有一稍弱的散射峰。DNA质量浓度在0.04~0.80 mg.L-1范围内,与RRS强度呈线性关系,检出限(3S/N)为0.023 mg.L-1。应用于测定合成样品中DNA含量并测得回收率为98.0%~104.0%。初步探讨了反应机理,盐酸吖啶黄与DNA间的相互作用包含有静电引力、π-π堆积力。  相似文献   

2.
在pH 6.38的三羟甲基氨基甲烷-盐酸缓冲溶液和溴代十六烷基吡啶存在下,维生素B_1与氯酚红结合生成的缔合物使共振瑞利散射显著增强并产生新的共振瑞利散射光谱,最大共振瑞利散射峰位于339nm处,维生素B_1的质量浓度在0.03~0.42mg·L~(-1)内与其对应的共振瑞利散射增强程度(ΔI/_(RRS))呈线性关系,检出限(3s/k)为0.004 2mg·L~(-1)。据此提出了溴代十六烷基吡啶增敏共振瑞利散射法测定药物中的维生素B_1的方法。应用此方法分析了维生素B_1药物,加标回收率在99.2%~102%之间,测定值的相对标准偏差(n=6)在2.1%~2.5%之间。  相似文献   

3.
建立了测定皮蛋中Hg的双波长共振瑞利散射新方法,研究了共振瑞利散射的光谱特征、共存物质的影响及反应机理。在pH 6.58的Tris-HCl缓冲介质中,Hg(Ⅱ)与快绿-溴代十六烷基吡啶结合生成三元络合物,使体系的双波长-共振瑞利散射(DWO-RRS)光谱显著增强,最大和次大的共振瑞利散射峰分别位于344 nm和470 nm波长处。当用双波长-共振瑞利散射(DWO-RRS)法测定时,Hg(Ⅱ)的质量浓度在0.005~0.50 mg/L范围内与体系的共振瑞利散射增强强度△I_(RRS)呈线性关系,检出限(3σ/S)为1.4 ng/mL,定量限为0.034 mg/kg。方法用于皮蛋中Hg的测定,回收率为98.2%~102%,相对标准偏差(n=5)为2.1%~2.7%。  相似文献   

4.
建立了一种快速、准确测定药物中酒石酸美托洛尔的双波长共振瑞利散射(DWORRS)新方法。在酸性Tris-盐酸介质中,刚果红与酒石酸美托洛尔及表面活性剂十六烷基三甲基溴化铵反应生成红色三元缔合物,使双波长共振瑞利散射显著增强并产生新的具有2个明显散射峰的共振瑞利散射(RRS)光谱,最大共振瑞利散射峰位于375 nm,另一共振瑞利散射峰位于515 nm,酒石酸美托洛尔在0.004~0.55 mg/L范围内与体系的RRS增强强度的绝对值(│△I_(RRS)│)呈线性关系,检出限为0.0032 mg/L(375 nm),0.0038 mg/L(515 nm)和0.0018 mg/L(DWO-RRS,375 nm+515 nm)。还探讨了RRS的光谱特征、适宜反应条件、反应机理及共存物质的影响。方法用于药物中酒石酸美托洛尔含量的测定,加标回收率为98.57%~102.1%,相对标准偏差为2.0%~2.5%。  相似文献   

5.
建立了快速测定药物及生物样品中奥扎格雷钠的共振瑞利散射(RRS)法。在弱碱性Tris-盐酸缓冲介质中,奥扎格雷钠与维多利亚蓝B反应生成离子缔合物,使共振瑞利散射信号显著增强,最大共振瑞利散射峰位于355 nm,在此处,奥扎格雷钠的质量浓度在0.002~0.4 mg/L范围内与共振瑞利散射增强程度△I_(RRS)呈线性关系,检出限为0.0018 mg/L。方法用于市售奥扎格雷钠药物、血液及尿样中奥扎格雷钠的测定,加标回收率为98.0%~102%,相对标准偏差为1.3%~1.8%。  相似文献   

6.
在pH 8.71的Tris-HCI缓冲介质中,结晶紫(CV)与苯唑西林(OXA)结合,使体系的共振瑞利散射(RRS)急剧增强并出现新的RRS光谱,最大共振瑞利散射峰位于380nm处,苯唑西林的浓度在0.08~0.8μg·mL-1范围内与散射强度(△1RRS)成良好的线性关系,据此建立了测定苯唑西林的共振瑞利散射法,检出...  相似文献   

7.
建立了一种快速测定药物中乌拉地尔的高灵敏共振瑞利散射(RRS)法,研究了RRS的光谱特征、反应条件及共存物质的影响。在p H 3.38的Tris-盐酸介质中,乌拉地尔与溴代十六烷基吡啶-偶氮氯膦Ⅲ反应生成三元离子缔合物,导致共振瑞利散射显著增强并产生新的RRS光谱。在最大共振瑞利散射峰374 nm波长处,乌拉地尔在0.002~0.37 mg/L范围内与缔合物的RRS增强强度的绝对值(│△IRRS│)呈线性关系,检出限为0.0016 mg/L。该法用于药物中乌拉地尔含量的测定,加标回收率为99.0%~99.7%,相对标准偏差(n=5)为1.6%~2.0%。  相似文献   

8.
建立了测定痕量大观霉素的共振瑞利散射(RRS)法。在弱碱性Tris-HCl缓冲介质中,大观霉素与橙黄Ⅳ相互作用后,共振瑞利散射显著增强,在352nm处的△IRRS最强。大观霉素的质量浓度在0.6~4.0mg/L范围内与△IRRS成正比,检出限(3Sb/S)为0.084mg/L。该法可用于市售大观霉素药物及人尿中大观霉素含量的测定,回收率为98.6%~101.5%。  相似文献   

9.
提出了测定痕量长春瑞滨(NVB)的共振瑞利散射(RRS)光谱法。在pH为2.2的BR缓冲体系中,NVB与曙红Y(EY)形成物质的量的比为1比1的离子缔合物,从而引起共振瑞利散射强度显著增强,其最大散射波长位于312nm。散射信号的增强(ΔIRRS)与NVB的质量浓度在0.06~3.0mg·L-1范围内呈线性关系,检出限(3σ)为1.7μg·L-1。方法应用于注射液和尿样中NVB的测定,加标回收率在99.8%~101%之间,测定值的相对标准偏差(n=5)在1.1%~2.2%之间。  相似文献   

10.
在pH=5.0—9.0的水溶液中, 硫化镉纳米微粒[(CdS)n]与蒽环类抗生素米托蒽醌(MXT)、 表柔比星(EPI)和柔红霉素(DNR)凭借静电引力及疏水作用力结合, 形成粒径更大的聚集体, 导致共振瑞利散射(RRS)的增强并产生新的RRS光谱, 最大的RRS峰位于292 nm(MXT体系)、 285 nm(DNR体系)和315 nm(EPI体系). 与此同时还观察到二级散射(SOS)和倍频散射(FDS)强度明显提高. 其最大SOS峰位于540 nm(MXT体系)和560 nm(EPI及DNR体系), 而最大的FDS峰分别位于335 nm(MXT体系)、 320 nm(EPI体系)和330 nm(DNR体系). 在一定条件下, 3种散射强度(ΔI)均与药物的浓度成正比, 反应具有高灵敏度, 对于3种药物的检出限在3.6—9.1 ng/mL之间. 其中(CdS)n-MXT体系灵敏度最高, 对MXT的检出限分别为4.1 ng/mL(RRS)、 3.8 ng/mL(SOS)和3.6 ng/mL(FDS). 据此发展了一种用纳米硫化镉作探针, 灵敏、 简便并快速测定蒽环类抗癌药物的共振瑞利散射新方法.  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.

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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   

19.
20.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

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