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1.
Based on the investigation of a non-ionic surfactant-salt-H2O liquid-liquid extraction system, general rules concerning salt selection are concluded and the mechanism of phase separation is explained. The extraction behavior of chlorpromazine hydrochloride (CPZ) and procaine hydrochloride (PCN) in such a system is studied. Research shows that the extraction efficiency of CPZ can amount to 96% by twice extraction, which means that quantitative extraction is realized, while that of PCN is 77%. This system produces distribution coefficients (KD) of 12.3 and 2.6, respectively, for CPZ and PCN. Extraction mechanism is deduced according to ultraviolet absorbance; and molecular fluorescence spectra change of the drugs in the system studied.  相似文献   
2.
冠醚型电极对局部麻醉药响应功能的研究   总被引:3,自引:0,他引:3  
用二苯并24-冠-8作为活性物质、邻苯二甲酸二(2-乙基)己酯为增塑剂制得PVC膜电极。电极对局麻药丁卡因、普鲁卡因和利多卡因具有能斯特响应,用于局麻药针剂的测定取得满意的结果。  相似文献   
3.
Simple two-parameter Hückel and Pitzer equations were used for the calculation of the activity coefficients of aqueous hydrochloric acid at 25°C up to a molality of 2.0 mol-kg–1. The data obtained by Harned and Ehlers(12,13) from galvanic cells without liquid junction were used in the analysis and the parameters obtained were compared to those obtained from all reliable data presented in the literature for HCl at this temperature. A good agreement between the parameters was always observed. The activity coefficients obtained by the new equations were compared to those suggested by Robinson and Stokes,(8) Hamer and Wu,(1) and Pitzer and Mayorga,(9) and good agreement was also found. The data from the most important literature data sets for HCl were also predicted using the new activity coefficient equations, and the magnitude of the resulting errors was close to the precision of the measurements, the errors forming an almost random pattern for all data sets.  相似文献   
4.
阿斯美胶囊中四种组分的高效液相色谱分析   总被引:2,自引:0,他引:2  
建立了反相高效液相色谱法测定阿斯美胶囊中氨茶碱、盐酸甲氧非那明、马来酸氯苯那敏及那可汀四种组分的含量。色谱柱为SpherisorbC8,5μm,200cm×40mmID,流动相为体积分数05%的三乙胺溶液(磷酸调节pH55)+乙腈+甲醇(550+368+82),检测波长为264nm,线性范围分别为:氨茶碱3125~250mg/L,γ=09996,盐酸甲氧非那明15625~1250mg/L,γ=10000,马来酸氯苯那敏25~200mg/L,γ=09999,那可汀875~700mg/L,γ=09999;回收率(n=3)分别为1012%,1008%,999%,995%;精密度:日内平均RSD(n=6)分别为07%,04%,04%,06%;日间平均RSD(n=3)分别为10%,10%,11%,12%。  相似文献   
5.
IR spectroscopy was coupled with the matrix isolation technique to study the molecular complex formed between C3O2 and HCl and its photodissociation. The vibrational frequencies of the complex were compared with those of HCl and C3O2 monomers. For C3O2, a bent structure was characterized in the solid environment.

The vibrational frequencies were calculated in the 4000–400 cm−1 range using an ab initio method at the MP2/6-31G** level for the most stable complex; these frequencies describe the hydrogen interaction with the central carbon atom of C3O2 (T complex). The measured shifts between the vibrational mode frequencies of the complex and monomers were in good agreement with the calculated values.

Broad-band UV irradiation ( > 230 nm) of the T complex leads preferentially to ketene chloride and carbon monoxide. Ketene chloride formation can be explained by the reaction between HCl and the carbene C2O, which results from photo-dissociation at the C=CO bond of C3O2.  相似文献   

6.
Glass capillaries coated with Chirasil-Val, a chirally functionalised polysiloxane, are capable in principle of resolving all protein amino-acid enantiomers in a single run and within a short analysis time, thus allowing for example the quantitative amino acid determination by enantiomer labelling. The elution characteristics of the individual amino acids however are also dependent upon the chemical nature of the capillary wall surface, and a surface pretreatment is found to be necessary if all protein amino acids are to be analysed. Of the various methods of pretreatment tested, etching of borosilicate glass with gaseous HCl followed by deposition of colloidal silicic acid is considered to be the most suitable.  相似文献   
7.
Liu LD  Liu Y  Wang HY  Sun Y  Ma L  Tang B 《Talanta》2000,52(6):991-999
Spectrophotometric determination of procaine hydrochloride is described. The procaine hydrochloride reacts with p-dimethylaminobenzalhyde in glacial acetic acid to form an Schiff base which is a yellow compound, and its maximum absorption wavelength is at 455nm, 455=3.46×104. The absorbance for procaine hydrochloride from 0.2 to 15 μg ml−1 obeys Beer's law. The linear regression equation of the calibration graph is C=5.866A−0.02, with a linear regression correlative coefficient is 0.9994 and relative standard deviation (RSD) of 1.7%; the detection limit is 0.1 μg ml−1; recovery is from 92.0 to 110.0%. Effects of reaction medium, temperature, gentamycin, beneylpenicillin, kanamycin, streptomycin, foreign ions, and stand for time on the determination of procaine hydrochloride have been examined. The results obtained by this method agreed with those by the official method (dead-stop titration). This method is rapid and simple, and can be used for the determination of procaine hydrochloride in injection solution of procaine hydrochloride.  相似文献   
8.
Simple two-parameter Hückel and Pitzer equations were used for the calculation of the activity coefficients of aqueous hydrochloric acid at temperatures 0–60°C up to a molality of 2.0 mol-kg–1. The data obtained by Harned and Ehlers(2,3) on galvanic cells without a liquid junction were used in the parameter estimations of these equations. These data consist of sets of measurements at the temperature intervals of 5°C. It was observed that all estimated parameters follow very simple equations with respect to temperature. They are either constant or depend linearly on the temperature. The values for the activity coefficient parameters calculated by these simple equations are recommended here. The recommended parameter values were tested by predicting the data of Gupta, Hills, and Ives,(5) consisting of cell measurements from 5 to 45°C and molalities up to 1.0 mol-kg–1, and the data of Bates and Bower,(4) which extend to 95°C but measurements were only made on molalities less than about 0.1 mol-kg–1. The activity coefficients obtained by the new equations were also compared to those calculated by the Pitzer equations with the parameter values determined by Saluja, Pitzer, and Phutela(6) from calorimetric data. The agreement observed was excellent up to a molality of 1.5 mol-kg–1 at temperatures from 0 to 60°C.  相似文献   
9.
In the present work, an extended Hulburt–Hirschfelder oscillator model is proposed as a means of simplifying potential energy functions for direct‐potential‐fit analyses. The new potential energy function is joined smoothly to the long‐range inverse‐power dispersion energy expression. The new model is employed in direct‐potential‐fits using spectroscopic line positions that involve the ground electronic states of the principal isotopologues of hydrogen iodide and carbon monoxide, and the ground and first singlet‐sigma excited states of hydrogen fluoride and hydrogen chloride. The present methodology is found to lead to compact, flexible, and robust representations for the potential energy that compare favorably with the results of past work where more complicated models were employed.  相似文献   
10.
建立了高效液相色谱(HPLC)同时测定染发剂中N,N-双(2-羟乙基)-p-苯二胺硫酸盐(DHPD)、N,N-二甲基-p-苯二胺硫酸盐(DMPD)、N,N-二乙基-p-苯二胺硫酸盐(DEPD)、N-苯基-p-苯二胺盐酸盐(PPD)4种p-苯二胺N位衍生物的方法。采用Agilent Eclipse XDB-C18柱(150 mm×4.6 mm,5μm)为固定相,25 mmol/L磷酸缓冲液(pH 6.0,含0.1%的辛烷磺酸钠)和乙腈为流动相,梯度洗脱,流速1.0 mL/min,柱温25℃,进样量20μL,检测波长250 nm和280 nm。各组分的线性范围为0.1~400 mg/L,相关系数r为0.999 2~0.999 9,检出限为18~108 mg.kg-1,定量下限为42~320 mg.kg-1,RSD<10%,加标回收率为83%~115%。该方法具有简便、快速、准确等特点,基本满足实际样品的分析要求。  相似文献   
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