阻抑速差催化光度法测定磺胺类药物

研究了磺胺嘧啶(SD),磺胺二甲嘧啶(SM2),抑制了碘催化As(Ⅲ)-Ce4+反应速率的条件,建立了阻抑速差光度法测定磺胺类药物的新方法。结果表明,在含0.01 mg/L I-,0.225 mol/L H2SO4,0.5 g/L NaCl,0.00125 mol/L As2O3和0.001 mol/L Ce4+溶液中测定SD和SM2的线性范围分别为2.25~3.75和2.0~3.5 mg/L;检出限为2.1×10-4和2.7×10-4g/L;表观摩尔吸光系数(L.mol-1.cm-1)为3.44×104和2.76×104。已用本法测定SD和SM2针剂和SM2片剂。     

溴氧化紫外分光光度法测定维生素C和多酚

研究了同时测定维生素C和多酚的新方法。在体积分数38%和47.5%的乙醇、6×10-5mol/LBr2、2.5×10-3mol/LKI水溶液中,维生素C和多酚类的表观摩尔吸光系数(L.mol-1.cm-1)分别为5.42×104、8.22×105和5.46×104、8.60×105,维生素C和多酚的相对标准偏差(RSD)分别为2.5%、2.3%和2.1%、2.6%,该法用于绿豆芽、酸橙、未熟苹果、青椒中的维生素C和多酚含量测定,回收率为95.78%～100.7%。     

简便吸收光谱法测定饮料中共存色素诱惑红和柠檬黄

建立了同时测定饮料中共存色素诱惑红和柠檬黄的简便吸收光谱法。在pH 7.2～8.7 Tris-HCl介质中,诱惑红和柠檬黄与双绿SF反应生成离子缔合物。诱惑红-双绿SF在可见光区有正吸收峰(496 nm)和负吸收峰(570 nm),诱惑红的质量浓度在0.03～12.4 mg/L范围内服从朗伯-比尔定律,表观摩尔吸光系数为1.79×104L/(mol·cm)(496 nm)和2.43×104L/(mol·cm)(570 nm),检出限为29μg/L (496 nm)和27μg/L(570 nm),定量限分别为0.78 mg/kg和0.73 mg/kg。柠檬黄-双绿SF在422 nm和660 nm处分别产生1个较强的正吸收峰,柠檬黄的质量浓度在0.04～13.4 mg/L范围内服从朗伯-比尔定律,表观摩尔吸光系数为2.13×104L/(mol·cm)(422 nm)和1.59×104L/(mol·cm)(660 nm),检出限为32μg/L(422 nm)和35μg/L(660 nm),定量限分别为0.87 mg/kg和0.95 mg/kg。当用双波长法测定时,表观摩尔吸光系(κ)为4.22×104L/(mol·cm)(诱惑红体系)和3.72×104L/(mol·cm)(柠檬黄体系),诱惑红体系的检出限和定量限分别为0.014 mg/L和0.38 mg/kg,加标回收率和相对标准偏差分别为98.0%～102%和2.3%～2.8%;柠檬黄体系的检出限和定量限分别为0.017 mg/L和0.46 mg/kg,加标回收率和相对标准偏差分别为97.5%～103%和1.1%～2.2%。该法适于饮料中诱惑红和柠檬黄的测定。     

基于灿烂绿与甜蜜素的显色反应测定饮料中甜蜜素

建立了测定饮料中甜蜜素的吸收光谱法。在弱酸性溶液中,甜蜜素与灿烂绿反应生成离子缔合物,在608 nm和636 nm处产生2个较强的正吸收峰,甜蜜素的质量浓度在0.05～3.6 mg/L范围内服从朗伯-比尔定律,表观摩尔吸光系数(κ)为5.12×10~4L/(mol·cm)(608 nm)和4.11×10~4L/(mol·cm)(636 nm),检出限为0.038 mg/L(608 nm)和0.041 mg/L(636 nm),定量限分别为25.2和27.2 mg/L。若将608 nm和636 nm叠加测定,表观摩尔吸光系数(κ)为9.23×10~4L/(mol·cm),检出限和定量限分别为0.02和13.3 mg/L,此法用于实际样品中甜蜜素的测定,加标回收率(n=5)和相对标准偏差(RSD,n=5)分别为97.7%～102%和1.0%～2.0%。该法适于苏打、果味及碳酸饮料中甜蜜素的测定。     

三重比光谱导数法同时测定氨基酸注射液中的三种芳香氨基酸

采用三重-比光谱导数分光光度法同时测定氨基酸注射液中的3种芳香氨基酸,讨论了测定酪氨酸、苯丙氨酸和色氨酸的实验条件.实验结果表明,在pH 7.4的NaH2PO4-NaOH缓冲溶液中,3种氨基酸的线性范围分别为:酪氨酸2.0×10-6～2.8×10-5 mol/L,苯丙氨酸2.0×10-5 ～1.6×10-3 mol/L,色氨酸4.0×10-7～1.6×10-6 mol/L.回收率在95%～105%之间.     

玫瑰精B光度法测定苯唑西林的含量

在pH=9.13的Tris-HCl缓冲体系中,玫瑰精B可与苯唑西林反应生成浅粉红色离子缔合物,产生两个明显的褪色峰.其最大褪色波长分别位于578 nm和494nm,表观摩尔吸光系数(ε)分别为8.70×104L/(mol·cm)和5.20×104L/(mol·cm).苯唑西林的浓度在0～0.6 mg/L范围内与溶液的褪...     

乙基曙红-溴化十六烷基吡啶光度法测定水样中阴离子表面活性剂

在弱酸性的HAC-NaAC缓冲介质中,将溴化十六烷基吡啶(CPB)与乙基曙红(EE)染料溶液混合,加入阴离子表面活性剂(AS),溶液颜色加深,最大吸收波长都在516nm处,且阴离子表面活性剂的浓度与溶液的增色程度呈良好线性关系。在最大吸收波长处,3种阴离子表面活性剂——十二烷基苯磺酸钠(SDBS)、十二烷基磺酸钠(SLS)及十二烷基硫酸钠(SDS)的浓度分别在0~2.05×10-5mol/L、0~2.08×10-5mol/L、0~2.04×10-5mol/L范围内遵守比尔定律,表观摩尔吸光系数分别为2.38×104、2.82×104和2.98×104L/(mol.cm),检出限分别为8.42×10-7、4.56×10-7和7.95×10-7mol/L。方法具有较高的灵敏度和良好的选择性,用于不同水样中AS的测定,结果满意。     

溴甲酚紫、溴甲酚绿光度法测定阿昔洛韦

在pH 3.30的NH2CH2COOH-NaCl-HCl缓冲介质中,阿昔洛韦(Aciclovir,ACV)可与溴甲酚紫(BCP)、溴甲酚绿(BCG)反应,形成离子缔合物,溶液颜色发生明显变化,其最大褪色波长分别为428 nm(BCP-ACV)、450 nm(BCG-ACV),在此波长处,阿昔洛韦的浓度与溶液褪色程度呈良好线性关系,可用分光光度法测定。在BCP-ACV、BCG-ACV体系的最大褪色波长处,ACV的浓度分别在0~2.69×10-5mol/L、0~2.58×10-5mol/L范围内遵守比耳定律,表观摩尔吸光系数分别为2.53×104L.mol-1.cm-1、1.79×104L.mol-1.cm-1,检出限分别为5.10×10-7mol/L、7.13×10-7mol/L。方法用于药品、血浆及尿液中阿昔洛韦的测定,结果满意。     

维多利亚蓝B-双波长分光光度法测定垃圾渗滤液中十二烷基磺酸钠

在pH 7.3的B-R缓冲溶液中,阴离子表面活性剂十二烷基磺酸钠(SDS)与维多利亚蓝B(VBB)以物质的量比2:1反应生成具有正吸收和负吸收的蓝色离子缔合物,最大正吸收波长为690 nm,最大负吸收波长为615 nm,线性范围分别为0.2～8.2 mg·L-1(正吸收)和0.2～6.8 mg·L-1(负吸收),表观摩尔吸光率为3.48×104L·mol-1·cm-1(正吸收)和2.14×104L·mol-1·cm-1(负吸收),采用双波长叠加测定,灵敏度可达5.60×104L·mol-1·cm-1,据此建立了测定SDS含量的双波长分光光度法.探讨了适宜的反应条件及垃圾渗滤液的预处理方法.该法用于垃圾渗滤液中SDS含量的测定,回收率在98.5 0A～101.0H之间,测定值的相对标准偏差(n=5)在0.8%～1.5%之间.     

流动注射化学发光法测定3种氟喹诺酮类药物

研究发现,氟喹诺酮类药物对可溶性Mn(-甲醛化学发光体系有强烈的增敏作用,结合流动注射技术,建立了3种氟喹诺酮类药物诺氟沙星、氧氟沙星和环丙沙星的流动注射化学发光新方法。在优化的实验条件下(2×10-4molMn(-3%甲醛-3mol/L磷酸),本方法测定诺氟沙星、氧氟沙星和环丙沙星的线性范围分别为1.0×10-7～1.0×10-5mol/L,1.0×10-7～1.0×10-5mol/L和3.0×10-7～5.0×10-5mol/L;检出限分别为3×10-8mol/L,3×10-8mol/L,1×10-7mol/L;相对标准偏差(5.0×10-6mol/L氟喹诺酮类药物,n=11)分别为2.6%,1.6%和2.8%。该方法已用于诺氟沙星胶囊中诺氟沙星的含量测定。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

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.     

非那雄胺合成工艺改进

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。     

Synthesis of phenolic components of Grains of Paradise

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.     

Study of hydration of two cements of different strengths

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, M_o, 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 600-700^oC. 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.     

Acid hydrolysis of carboxymethylcellulose of low degree of substitution

Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.     

恶臭嗅辨实验室建设探讨

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。     

氯氧化镁生成热的研究

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^-。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

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.

     

Estimation of Kinetic Parameters of Thermal Oxidation of Ilmenite

The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe₂O₃. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.