1-苯基-3-甲基-4-苯甲酰基-吡唑酮-5与中性磷(膦)萃取剂协同萃取镧(Ⅲ)

研究了1-苯基-3-甲基- 4-苯甲酰基-吡唑酮-5(HPMBP)和中性有机磷(膦)类萃取剂Cyanex 471X(TIBPS,B)在硝酸介质中对稀土元素La（Ⅲ）的萃取,用斜率法和恒摩尔法探讨了萃取机理,确定了萃合物的组成为La(NO3)2·PMBP·B,计算了萃取平衡常数.比较了HPMBP与Cyanex 471X、Cyanex 921、Cyanex 923、Cyanex 925、DEH/EHP、P350及TBP的单独及混合体系萃取La（Ⅲ）的性能,结果表明所有混合体系对La（Ⅲ）均有协同效应,其中HPMBP与Cyanex 923、Cyanex 921、Cyanex 925的混合体系是萃取La（Ⅲ）的有效体系.     

核磁共振法研究1-苯基-3-甲基-4-苯甲酰吡唑酮(5)在溶剂中的异构体性质

1959年,B.S.Jensen制得一系列酰代吡唑酮,并指出这类化合物可用于多种金属元素的液液萃取,但没有萃取的实验数据。本文的部分作者曾于1962年复制了1-苯基-3-甲基-4-苯甲酰吡唑酮(5),并研究了它的萃取性质及其萃合物。继后,又研究了它对钼、钨的萃取以及钼氧螯合物的晶体结构。这种萃取剂对金属的分析分离研究在国内外也受到广泛重视。然而,对它在溶剂中的异构互变平衡及其异构体的性质,尚不清楚。本文试图利用核磁共振方法,在不破坏异构体互变平衡的条件下,观测α-质子的信号,从而阐明这个螯合剂在溶剂中的异构体性质。     

固相微萃取-气相色谱法测定工业苯酚中的2-甲基苯并呋喃和2,4-二苯基-4-甲基-1-戊烯

建立了工业苯酚中有机杂质的固相微萃取-气相色谱(SPME-GC)分析方法。实验考察了SPME萃取温度和萃取时间的影响,同时也优化了热解吸时间。优化后的萃取温度为20 ℃,萃取时间为10 min,热解吸时间为30 s。使用此法对工业苯酚样品中的两种主要有机杂质进行了分析检测,结果表明: 2-甲基苯并呋喃和2,4-二苯基-4-甲基-1-戊烯分别在0.05～1.06 mg/L和0.05～0.99 mg/L范围内线性关系良好(r2分别为0.990和0.992),检出限分别为0.5和1.6 μg/L。在0.1 mg/L的添加水平下,2-甲基苯并呋喃和2,4-二苯基-4-甲基-1-戊烯的回收率分别为104%和113%。该方法具有简单、快速、灵敏度高等优点,适合于工业苯酚中这两种主要痕量有机杂质的准确定量分析。     

超声波萃取与索氏萃取丙烯腈-丁二烯-苯乙烯中四溴双酚A的比较研究

采用气相色谱-质谱法对超声波萃取与索氏萃取丙烯腈-丁二烯-苯乙烯(ABS)中四溴双酚A进行了比较研究。超声波萃取的最优试验条件:溶剂为二氯甲烷,温度为30℃,时间为60min;索氏萃取的最优试验条件:溶剂为甲苯,回流次数为每小时4次,时间为12h。四溴双酚A的质量浓度在1.00~100mg·L-1范围内与其峰面积呈线性关系。索氏萃取的萃取率高于超声波萃取的萃取率,索氏萃取的相对标准偏差(n=6)为2.1%,加标回收率在80.4%~85.7%之间。     

4,4''''-癸二酰-双-(1-苯基-3-甲基-5-吡唑啉酮)和中性磷萃取剂对铀(Ⅵ)的协同萃取

或许是考虑到溶解度的原因,迄今应用4,4′-癸二酰-双-(1-苯基-3-甲基-5-吡唑啉酮)(简称为DBPMP或H_2A)所进行的萃取研究,都是采用氯仿作为稀释剂。然而,氯仿属于A型受电子溶剂,能和具有给电子原子氧的DBPMP及中性磷萃取剂TBP或TOPO生成分子间氢键而缔合,从而降低萃取的分配比。若改用N型惰性溶剂作为稀     

苯-丙-硅共聚物固相微萃取涂层制备及性能研究

合成了苯乙烯-丙烯酸丁酯-乙烯基三乙氧基硅氧烷三元共聚物,并对其结构进行了表征,对其热稳定性、粘度、与纤维的结合能力等物理性能进行了测试。使用自制固相微萃取装置,研究了该聚合物作为固相微萃取涂层的应用性能,对水中小分子烷基苯、氯苯、硝基苯进行了萃取实验,将萃取结果与商品涂层萃取结果进行了比较,令人满意。实验数据表明,苯-丙-硅三元共聚物作为固相微萃取涂层性能优良。     

基于冷冻熔炼的液-液萃取样品富集技术研究

本文通过对区域熔炼原理及液-液萃取技术的探讨,发展了一种简单高效的基于冷冻熔炼的液-液萃取样品富集新技术.通过理论分析,探讨了冷冻熔炼、常温液-液萃取以及冷冻熔炼液-液萃取中溶质浓度的分布特征,通过富集效率的探讨证明冷冻熔炼液-液萃取技术是液-液萃取与区域熔炼技术的结合.通过葡萄汁样品的分析,对该技术进行了评价.理论计算求得冷冻熔炼液-液萃取中相应组分的富集效率为4.5,而试验测得富集效率为4.8,两者结果一致,说明冷冻熔炼液-液萃取是一种简单高效的样品富集技术.     

超声萃取-高效液相色谱法测定烟草中β-D-吡喃葡萄糖-3-氧代-α-紫罗兰醇苷

建立了一种用超声波辅助萃取-高效液相法测定烟草中β-D-吡喃葡萄糖-3-氧代-α-紫罗兰醇苷含量的新方法。以甲醇为萃取溶剂,超声萃取条件经过正交实验优化,优化后的条件为料液比1:40(m/V,g/mL)、萃取功率160W,萃取时间20 min。所得萃取液经大孔吸附树脂柱层析法分离后,用Waters SunFireC18(150 mm×4.6 mm,5μm)色谱柱分离,紫外检测器(波长为243nm)检测,流动相为V(乙腈):V(水)=20:80;流速1 mL/min。β-D-吡喃葡萄糖-3-氧代-α-紫罗兰醇苷在0.01～1 mg/mL范围内线性关系良好,相关系数为0.9994,相对标准偏差为1.8%,检出限为0.05μg/mL,平均回收率为87.80%。该方法适用于β-D-吡喃葡萄糖-3-氧代-α-紫罗兰醇苷的定量分析。     

H2BPMOPP和PMBP协同萃取Ln3+的研究

4-酰代双吡唑啉酮对金属离子具有很强的萃取能力。本文在合成萃取剂1，2-双(1′-苯基-3′-甲基-5′-氧代吡唑-4′-基)邻苯二酮(H2BPMOPP-H2A)的基础上，     

t-BAMBP萃取-原子吸收分光光度法测定矿物中微量铷、铯

利用4-叔丁基-2-（α-甲苄基）酚（t-BAMBP）萃取矿物中微量的铷和铯,再利用原子吸收分光光度法测定其在萃取剂中的浓度．并对稀释剂的选择、萃取酸碱度、相比影响、萃取时间及干扰离子等进行了研究．实验结果表明,检出限分别为铷:0.02μg/g,铯:0.08μg/g。标准浓度在0~200μg/50mL时,线性关系大于0.9989,样品加标回收率为96.4%~104.4%之间,相对误差小于1%．     

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。     

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.     

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.     

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^-。     

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.     

Mechanism of action of base-catalyzed oxygenation of phenol derivatives

Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.     

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.