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51.
Abstract Room temperature ionic liquids (RTILs) are mainly referred to melting salt systems composed by organic cations and organic or inorganic anions that exhibit liquid-like behavior at or around room temperature. Chloroaluminate room temperature ionic liquid (chloroaluminate RTILs) is one kind of RTIL synthesized by chloride quaternary ammonium salts and anhydrous AlCl3. Three kinds of chloroaluminate RTILs were synthesized using trimethylamine hydrochloride (TA), 1-butylpyrinium chloride (BPyC), or 1-methyl-3-alkylimidazolium (BMIC), respectively, with anhydrous AlCl3 and their application in reducing the content of olefin in FCC gasoline from the Jinzhou Petrochemical Corporation was studied. The effects of chloroaluminate RTIL component and operation conditions on olefin reduction were investigated as well as the repeatability of chloroaluminate RTILs. The results show that at room temperature, when the ratio of anhydrous AlCl3 to quaternary ammonium (mole/mole), the solvent-oil ratio (g/g), and the reaction time were 2/1, 20/100, and 1/2 h, respectively, the content of olefin in FCC gasoline was deduced more than 30%. The chloroaluminate RTILs could be used at least four times on the basis of keeping their activity. 相似文献
52.
Sameh M. Abdel-Hamid Seham E. Abdel-Hady Abdel-Hamid A. El-Shamy Hadir F. El-Dessouky 《Drug development and industrial pharmacy》2013,39(10):1078-1089
The antispasmodic drug mebeverine hydrochloride was formulated into a film-forming gel to be used as a topical local anesthetic. A mixture of cellulose derivatives was used as a base. Additives were used to enhance the release as well as the residence time. Formulations were characterized in terms of drug release, mucoadhesion and rheology. Clinically, the selected formula has shown faster onset (p?=?0.0156), longer duration (p?=?0.0313), better film residence (p?=?0.0313), and no foreign body sensation (p?=?0.0313) in comparison to Solcoseryl® dental paste. Histopathological examination showed no change in inflammatory cells count, concluding that this topical anesthetic is efficacious and safe orally. 相似文献
53.
该文利用核磁共振实验技术详细研究了抗心律失常药物盐酸普罗帕酮的化学结构特征,并借助二维核磁共振实验技术对盐酸普罗帕酮的氢谱和碳谱进行了完全归属,为该类化合物的结构解析提供了有益的分析依据。 相似文献
54.
Ashok Mahajan Naazneen Surti Pooja Koladiya 《Drug development and industrial pharmacy》2018,44(3):463-471
The aim of the present study was to improve the dissolution and flow properties of lurasidone hydrochloride (LH) by solid dispersion adsorbate (SDA) technique. Solid dispersions (SDs) of LH were prepared by fusion method using Poloxamer P188. The melt dispersion was adsorbed onto the porous carrier Florite (calcium silicate). A 32 factorial design was employed to quantify the effect of two independent variables, namely ratio of carrier (Poloxamer 188) and LH in SD and ratio of adsorbent (Florite) to SD. SDA granules of LH were studied for flow properties and characterized using differential scanning calorimetry, scanning electron microscopy, and X-ray diffraction. Tablets of optimized composition of SDA granules (equivalent to 20?mg of drug) and plain tablets were prepared by direct compression method. The dissolution studies were carried out in Mcllvaine buffer (pH 3.8) as per USFDA guidelines and characterized for parameters such as percent dissolution efficiency, t50, and Q30. Tablets prepared from SDA granules showed almost four-fold increase in cumulative percentage drug release as compared to tablets prepared from plain LH. The value of dissolution efficiency was enhanced from 49.60% for plain tablets to 94.15% for SDA tablets. SDA granules did not show any change in drug release and X-ray diffraction pattern after storage at 40?°C/75% of RH for 3?months, which confirms that Florite prevented conversion of drug from amorphous form to crystalline form improving physical stability of the amorphous state of LH. 相似文献
55.
56.
乙苯甲喹唑啉酮盐酸盐合成方法的改进 总被引:1,自引:0,他引:1
以邻乙酰氨基苯甲酸为原料,在POCl3作用下与2-乙基苯胺缩合得3-(2-乙基苯基)-2-甲基-4-(3H)-喹唑啉酮盐酸盐,其条件为:以甲苯为溶剂,邻乙酰氨基苯甲酸与2-乙基苯胺摩尔比为1:1,反应时间3h,产物收率为80%。 相似文献
57.
本文报道了一种测定克咳敏的新方法 ,用硅钨酸作为电活性物质 ,将离子敏感场效应晶体管与药物敏感膜相结合 ,制成药物敏感场效应晶体管传感器 ,测定克咳敏的线性范围为 5 .0× 10 -2 ~ 5 .0× 10 -5mol/L ;适宜的 pH范围为 4 .0~ 7.5 ;响应灵敏度为 5 9.5mV/Pc.用该传感器测定克咳敏片剂的含量 ,结果和药典方法相一致 . 相似文献
58.
本文对柳杉KP浆的高白度漂白方法进行了研究。研究表明,采用硫酸盐法能够煮出卡伯值在28~32范围内的可漂浆,而且细浆得率高。采用C-Eop-HA-P四段漂(C-氯化,Eop-添加H2O2的氧碱抽提,HA-高温次氯酸盐漂后直接酸处理,P-过氧化氢漂白),能够将柳杉KP浆漂到白度88%以上,而且漂白得率达94%,返黄值仅0.3左右,漂后浆的强度比原浆强度约下降10%(打浆度42°SR)。 相似文献
59.
Okonogi S Khongkhunthain S Bunyaratavej P Thusaphorn T Umpriwan R 《Drug development and industrial pharmacy》2004,30(4):347-357
The current research study is based on the design and development of a sol-gel biodegradable controlled-release formulation for use in the treatment of periodontal diseases. Glycerylmonooleate (GMO) was used as a main composition in the gel base. The influence of various additives, e.g., glycerylmonostearate (GMS), methylcellulose (MC), surfactants, and triglycerides, in GMO formulations on rheologic and swelling properties and release characteristics was described. It was demonstrated that the surfactants and triglycerides affected rheologic behavior, whereas GMS and MC influenced both rheologic and swelling properties of the bases. The release study revealed that drug released from the gel bases depended on the square root of time. The kinetics can be explained by the Higuchi's diffusion theory. Some polyols could enhance drug release from the gel. The stability results suggested that the dental gels obtained should be kept in the low temperature range. 相似文献
60.
To select a suitable formulation for the development of transdermal drug-delivery system of diltiazem hydrochloride. Transdermal patches of the drug, employing different ratios of polymers, ethylcellulose (EC), and povidone (PVP) were developed and evaluated for the potential drug delivery using depilated freshly excised abdominal mouse skin. The influence of different film compositions on in vitro drug permeation into receptor fluid were studied using a modified Franz diffusion cell. The cumulative amount of drug was found to be proportional to the square root of time, i.e., Higuchi kinetics. From this study, it was concluded that the films composed of povidone:ethylcellulose (1:2) should be selected for the development of transdermal drug-delivery system of diltiazem hydrochloride, using a suitable adhesive layer and backing membrane, for potential therapeutic use. 相似文献