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51.
为了利用半导体光催化和硫酸根自由基高级氧化技术协同作用处理抗生素废水,采用溶剂热法制备三维结构的钼酸铋(Bi2MoO6)微球,并在可见光照射下激发Bi2MoO6进而活化过一硫酸氢盐(PMS)处理含盐酸四环素(TC)废水。利用扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、紫外-可见漫反射光谱(UV-Vis DRS)等对样品形貌特征、晶格结构、光学性能进行表征。结果表明,Bi2MoO6纳米片组成的三维微球具有良好的吸附和可见光催化降解TC能力,活化PMS协同作用可以进一步提高系统降解TC的效率。通过静态实验,考察催化剂使用量、PMS初始浓度、环境共存阴离子(Cl-、CO2-3、NO-3)和腐殖酸(HA)对可见光激发Bi2MoO6活化PMS降解TC性能的影响。自由基捕获实验表明,·OH、SO-4·、O-2·和h+等活性基团在可见光激发Bi2MoO6活化PMS催化降解TC过程中都做出了贡献。 相似文献
52.
将带有胍基抗菌官能团的聚六亚甲基盐酸胍(PHGC)与甲基丙烯酸环氧丙酯(GMA)反应,制备了含碳碳双键官能团的功能化聚六亚甲基盐酸胍。利用紫外分光光度法测定了反应转化率,并考察了溶剂、反应物配比、反应时间及温度对反应转化率的影响规律。采用FT-IR、Raman、NMR和TG对功能化聚六亚甲基盐酸胍的组成、结构和热稳定性进行了表征。结果表明,在DMSO溶剂中,当GMA与PHGC摩尔比为1:1,在60℃下反应60 h后,反应转化率可达75%,且合成的功能化聚六亚甲基盐酸胍具有良好的热稳定性。功能化聚六亚甲基盐酸胍可用作大分子单体,与其他单体共聚制备具有抗菌性能的聚合物和微球。 相似文献
53.
本文建立了用甲醛溶液吸收-盐酸副玫瑰苯胺分光光度法测定白砂糖中二氧化硫的方法.该法用甲醛代替汞盐,减少了对环境的污染.样品经处理后加入甲醛,样液中二氧化硫与甲醛生成稳定的羟基甲基磺酸,加氢氧化钠后,与盐酸副玫瑰苯胺作用,生成紫红色化合物,在579 nm处测定其吸光度.白砂糖中二氧化硫浓度在0~60 mg/kg范围内与吸光度值呈良好的线性关系(r=0.9998),检出限为0.81 mg/kg.样品测定的相对标准偏差在2.8%~4.1%,回收率在93.8%~98.6%之间.与国标方法测定结果比较,两者无显著性差异,结果令人满意. 相似文献
54.
本文以邻氨基苯甲酸为原料,经重氮化后,在表面活性剂PEG-600和少量锌粉存在下,70℃时经亚硫酸钠还原、20~25%的盐酸酸析后制得邻羧基苯肼盐酸盐,产率83.4%,含量(HPLC)≥99.5%,邻氨基苯甲酸:亚硝酸钠:盐酸:亚硫酸钠为1.0:1.02:3.0:2.5(mol/mol),邻氨基苯甲酸:PEG-600:锌粉为1.0:0.02:0.05(W/W)。 相似文献
55.
Kholoud Arafa Rehab N. Shamma Omaima N. El-Gazayerly 《Drug development and industrial pharmacy》2018,44(7):1158-1170
Purpose: Metformin hydrochloride (MF) repurposing as adjuvant anticancer therapy for colorectal cancer (CRC) proved effective. Several studies attempted to develop MF-loaded nanoparticles (NPs), however the entrapment efficiency (EE%) was poor. Thus, the present study aimed at the facile development of a new series of chitosan (CS)-based semi-interpenetrating network (semi-IPN) NPs incorporating Pluronic® nanomicelles as nanocarriers for enhanced entrapment and sustained release of MF for efficient treatment of CRC.Methods: The NPs were prepared by ionic gelation and subsequently characterized using FTIR, DSC, TEM, and DLS. A full factorial design was also adopted to study the effect of various formulation variables on EE%, particle size, and zeta-potential of NPs.Results: NPs had a spherical shape and a mean particle size ranging between 135 and 220?nm. FTIR and DSC studies results were indicative of successful ionic gelation with the drug being dispersed in its amorphous form within CS-Pluronic® matrix. Maximum EE% reaching 57.00?±?12.90% was achieved using Pluronic®-123 based NPs. NPs exhibited a sustained release profile over 48?h. The MF-loaded NPs sensitized RKO CRC cells relative to drug alone.Conclusion: The reported results highlighted the novel utility of the developed NPs in the arena of colon cancer treatment. 相似文献
56.
Side‐chain polyesters were synthesized from N‐octyl‐, N‐dodecyl‐ or N‐hexadecyl‐diethanolamine and succinic acid anhydride. These polyesters were then transformed into polyester hydrochlorides by protonation of the amino groups using different amounts of HCl (20–100 mol%). Above 60 mol% the reaction is not quantitative and a degree of protonation of up to 88% is obtained. The structures of the synthesized polyesters and their hydrochlorides were determined by 1H nuclear magnetic resonance spectroscopy. The thermal properties of the synthesized polyesters and their hydrochlorides were also studied using differential scanning calorimetry in relation to the side‐chain length and the degree of polyester protonation. The polyester with octyl side chains and its hydrochlorides were amorphous liquids at room temperature, while the polyester and polyester hydrochlorides with hexadecyl side chains formed a smectic crystalline phase, SmB, or its tilted analogues. The polyester with a dodecyl side chain was also an amorphous liquid at room temperature, while its hydrochlorides with various degrees of protonation were smectic liquid crystals, as determined by X‐ray diffraction. By simply varying the degree of protonation the liquid crystal isotropization temperature was increased from 32 °C to 82 °C. Copyright © 2011 Society of Chemical Industry 相似文献
57.
58.
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
59.
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
60.
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