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1.
大黄的非线性化学指纹图谱研究   总被引:1,自引:0,他引:1  
通过别洛索夫-扎鲍京斯基(B-Z)振荡反应对不同来源大黄进行定性分析,将大黄粉末加入H2SO4-MnSO4-CH3COCH3-NaBrO3中,组成化学振荡体系,用电化学工作站记录数据,并对化学试剂的浓度、反应温度、大黄用量等条件进行了考察,确定体系的最佳实验条件,获得了不同来源大黄的非线性化学指纹图谱.通过对大黄非线性化学指纹图谱的研究,发现不同来源的大黄的指纹图谱主要参数有较大区别.该方法简便,准确,可靠,可方便地用于不同来源大黄的定性分析.  相似文献   

2.
本文提出了BrO3-Ce4+-H2SO4-丙二酸/苹果酸复合有机底物化学振荡体系,并将其用于研究中药的电化学指纹图谱.考察了振荡体系中各组分的浓度、温度、中药加入量、浸泡时间等因素对振荡图谱特异性的影响,确定了最佳组成及测试条件.研究结果表明,非线性电化学指纹图谱可用于鉴别和评价中药的真伪、药效、道地性等.该方法快速、...  相似文献   

3.
介绍了医药类院校物理化学实验“D-101大孔树脂对根皮苷的吸附动力学”。从该实验的背景、意义与目的、原理、操作、数据处理、讨论与教学建议等方面进行了详细介绍。在操作部分附上了各步原始操作记录的样例,在数据处理部分附上了处理数据与绘图拟合的样例,并附上了已录制的实验教学及数据处理指导视频网址。所设计的实验兼具了鲜明的物理化学特征与制药行业特点,在实现了基础化学实验操作教学目的的同时,也起到了与医药领域各专业实验教学紧密支撑的衔接作用。  相似文献   

4.
不同产地中药赤芍在振荡体系中的化学指纹图谱研究   总被引:1,自引:0,他引:1  
采用H2 SO4 - CH2 (COOH)2 - Ce2( SO4)3- KBrO3化学振荡体系,研究了中药赤芍的化学指纹图谱,并对温度、赤芍用量进行了考察,确定体系的最佳实验条件为12 mL 3.0 mol/L H2SO4溶液、6 mL 0.4 mol/LCH2( COOH)2溶液、3 mL 0.005 mol/L ...  相似文献   

5.
采用振荡技术,研究了中草药及中成药板蓝根-丙酮-溴酸钾-硫酸锰-硫酸的振荡反应新体系的振荡指纹图谱.测定了不同浓度,不同温度下板蓝根的振荡反应图谱,得到了不同温度、浓度下的反应诱导期、振荡周期及振荡寿命,得出诱导期表观活化能Ein=135.054kJ/mol,振荡周期平均活化能Ep=71.802kJ/mol;初步研究此...  相似文献   

6.
柴胡舒肝丸的毛细管电泳指纹图谱及其黄芩苷含量的测定   总被引:2,自引:0,他引:2  
孙国祥  闫娜娜  丁国瑜 《色谱》2010,28(11):1077-1083
建立了柴胡舒肝丸(Chaihu Shugan Pill, CHSGP)的毛细管区带电泳指纹图谱(capillary electrophoresis fingerprint, CEFP),并采用内标法测定了黄芩苷的含量。以50 mmol/L硼砂-150 mmol/L磷酸二氢钠-50 mmol/L磷酸氢二钠(1:1:1, v/v/v)(含5 mmol/L庚烷磺酸钠)为背景电解质(BGE)溶液,采用未涂层石英毛细管(总长度75 cm,有效分离长度63 cm,内径75 μm),以色谱指纹图谱分离量指数(RF)为目标函数优化实验条件,在紫外检测波长265 nm、运行电压11 kV条件下,以黄芩苷峰为参照物峰,确定了22个共有指纹峰,建立了CHSGP的CEFP,通过对20批样品聚类分析确定用其中13批生成对照CEFP(RCEFP),以此RCEFP为标准用系统指纹定量法鉴别20批柴胡舒肝丸质量。结果其中的4批化学成分数量和分布比例不合格,4批含量明显偏低,其他12批完全合格。采用内标法测定黄芩苷的含量,在5~200 mg/L范围内线性良好(r=0.9999),平均回收率(n=9)为98.2%。该法具有较好的精密度和重现性,为柴胡舒肝丸的质量控制提供了一种新的参考。  相似文献   

7.
铁皮石斛的裂解气相色谱指纹图谱及其系统聚类分析   总被引:4,自引:0,他引:4  
王丽丽  王聪  潘再法  孙法 《色谱》2008,26(5):613-617
采用裂解气相色谱/质谱法(Py-GC/MS)测定了10种不同产地的铁皮石斛并结合系统聚类分析法比较了这些铁皮石斛的指纹图谱,采用释放气体分析法考察了裂解温度对指纹图谱的影响。结果表明,0.4 mg样品在450 ℃下可瞬间裂解,10种样品的指纹图谱具有相似性,且重现性好;采用系统聚类分析能区别不同产地的样品。本法快速、简便、准确,不失为药材质量控制的良好方法。  相似文献   

8.
以H2SO4 - KBrO3- MnSO4- CH3COCH3为电化学振荡反应体系,采用电化学方法获取黄芩不同提取条件下电化学指纹图谱,根据指纹图谱特征参数诱导时间考察黄芩提取液总成分含量,优化黄芩提取的最佳工艺为: 采用10倍量的水,提取3次,每次2 h.结果表明,黄芩提取液浓度和诱导时间(tin)呈良好的线性关系,其线性回归方程为tin=-570C+7176(r=0.9970),线性范围为5.0~12.2 g/L.  相似文献   

9.
胡芯  陈泽  闫涛  胡锴  赵发琼  黄驰  刘欲文 《大学化学》2020,35(4):137-144
针对现有物理化学实验教材中的“B-Z振荡反应实验”进行了重新设计,加入了基于反应机理的复杂反应动力学数学处理及B-Z反应在分析检测中的应用。新的实验设计使用的仪器、试剂等与原方案相同,在保留原实验趣味性、前沿性的基础上增加了更多的理论知识点,提高了实验的自主性、设计性,加大了实验的难度。在教学模式上新的实验设计更易于课上、课下相结合:课下完成理论模拟探究振荡周期的影响因素,初步确定实验方案(反应条件),课上实施、验证、优化实验设计,并拓展B-Z振荡反应的应用。新实验设计更能加深学生对非线性非平衡态动力学与耗散结构的认识,理解B-Z振荡反应分析检测应用与反应机理间的联系。关于非线性动力学的数学处理方法可以应用于科学研究与生产实践中。  相似文献   

10.
大青叶的毛细管电泳指纹图谱研究   总被引:19,自引:0,他引:19  
采用高效毛细管电泳法,紫外检测波长228nm,电压12.5kV,以硼酸(100mmol/L):硼砂(50mmol/L)=11:10(调pH11)为背景电解质进行指纹图谱研究。建立了大青叶药材的电泳指纹图谱(CEFP)。以胞苷峰为参照物峰,确定了18个共有峰,测定了10个产地大青叶的CEFP与共有模式间具有良好的相似性,用色谱指纹图谱指数对其进行评价。所建立的CEFP具有较好的重现性,可用于大青叶药材的质量控制。  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   

19.
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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