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排序方式: 共有1111条查询结果,搜索用时 15 毫秒
91.
以2-羟甲基-4-(甲氧基丙氧基)-3-甲基吡啶盐酸盐为起始原料,经氯代、缩合反应"一锅法"制得2-{[3-甲基-4-(3-甲氧基丙氧基)-2-吡啶基]甲基亚磺酰基}-1H-苯并咪唑,再经氧化反应得到雷贝拉唑。 相似文献
92.
93.
高效液相色谱法测定盐酸度洛西汀中1-萘酚的含量 总被引:1,自引:0,他引:1
建立一种适用于测定盐酸度洛西汀中1-萘酚的测定方法。色谱柱为AgilentC18柱(5μm,4.6mm×250mm);磷酸盐缓冲溶液(pH=5.8)-乙腈(63∶37)为流动相;检测波长为230nm;柱温为30℃;流速1.0mL/min;进样体积为10μL。样品中盐酸度洛西汀和1-萘酚分离度良好,1-萘酚的最低检测限为0.132ng。所建立的方法简便、快速,可准确地分离盐酸度洛西汀中的1-萘酚,并能有效监控产品中的主要有关物质。 相似文献
94.
Zhiwei Zhao Yueyue Liu Xing Liu Yuan Liu Jingwen Chen Shixia Chen Shuguang Deng Jun Wang 《American Institute of Chemical Engineers》2023,69(6):e18046
The one-step adsorptive separation of high-purity ethylene (C2H4) from a ternary gas mixture (C2H2/C2H4/CO2) is challenging and has not been reported on porous carbons. Herein, we report camphor seeds husk-derived ultramicroporous carbons (CSHs) show high affinities toward acetylene (C2H2) and carbon dioxide (CO2) over C2H4. The optimized CSH-2-700 with high heteroatom contents and centered pore size distributions shows high C2H2 adsorption capacity (2.24 mmol g−1) and record ideal adsorbed solution theory (IAST) C2H2/C2H4 selectivity (10.2) among one-step C2H4 purification adsorbents. Meanwhile, CSH carbons are the only carbon adsorbents that preferentially adsorb CO2 over C2H4, with a CO2/C2H4 selectivity of 1.9 under ambient conditions. Furthermore, dynamic breakthrough experiments verified its feasibility for one-step C2H4 purification from a three-component C2H2/C2H4/CO2 gas-mixture. 相似文献
95.
Yingjie Guo Zan Chen Xue Hu Yawei Du Cuijia Duan Claudia Li Sibudjing Kawi Yinhui Li 《应用聚合物科学杂志》2024,141(3):e54818
Imino hypercrosslinked polymers (NH-HCPs), amino hypercrosslinked polymers (NH2-HCPs), and carboxyl hypercrosslinked polymers (COOH-HCPs) were synthesized through cross-linking and Friedel-Crafts reactions to serve as highly efficient adsorbents for doxycycline hydrochloride (DOX) in water. These polymers, NH-HCPs, NH2-HCPs, and COOH-HCPs, exhibited specific surface areas measuring 450, 267.576, and 94.39 m2/g, respectively. The adsorption kinetics of DOX onto these polymers were consistent with the pseudo-second-order model, while the adsorption isotherms followed the Langmuir model (NH-HCPs) and Freundlich model (NH2-HCPs and COOH-HCPs), respectively. The maximum DOX adsorption capacities for NH-HCPs, NH2-HCPs, and COOH-HCPs were 166.82, 132.43, and 72.07 mg/g, respectively. Simulation results indicated that COOH-HCPs exhibited the strongest adsorption capability due to a substantial presence of oxygen and nitrogen groups on its surface, enabling the formation of hydrogen bonds with DOX. However, its actual adsorption capacity was the lowest among the polymers, indicating that structural adjustments played a more significant role in improving adsorption performance compared to functional adjustments. Adsorption experiments conducted with NH-HCPs and NH2-HCPs further supported this hypothesis. The primary DOX adsorption mechanism of NH-HCPs, NH2-HCPs, and COOH-HCPs involved the H-bonding of oxygen and nitrogen functional groups, along with other mechanisms such as π-π conjugated effects, pore-filling effects, electrostatic interactions, and acid–base interactions. Overall, this study demonstrates the effectiveness of NH-HCPs, NH2-HCPs, and COOH-HCPs in DOX removal from water, highlighting the significant influence of structural adjustments on adsorption performance. 相似文献
96.
该研究将L-半胱氨酸盐酸盐添加到面团中制作曲奇,研究了不同添加量(0.3、0.6、1.0、1.5 g/kg)L-半胱氨酸盐酸盐对4种有害醛类含量、曲奇外观和挥发性物质的影响。结果表明:添加后,曲奇的接受度高于未添加对照组,且4种有害醛类的含量显著降低。当L-半胱氨酸盐酸盐添加量为1.5 g/kg时,曲奇中5-羟甲基糠醛、3-脱氧葡萄糖醛酮、乙二醛和丙酮醛含量分别降低28.75%、62.73%、46.27%、36.59%。微固相萃取-气质联用结果显示:添加后,曲奇的挥发性醛、醇和吡嗪类物质含量增加,大部分酮类物质含量减少。细胞毒性实验结果显示:添加L-半胱氨酸盐酸盐的曲奇水提取物添加对人胃粘膜上皮细胞活力有促进作用。结合实验分析,曲奇最适L-半胱氨酸盐酸盐添加量为1.0 g/kg。 相似文献
97.
Shiv Sankar Bhattacharya 《Journal of Adhesion Science and Technology》2013,27(10):925-942
The main objective of this research work was to fabricate and evaluate adhesive matrix-type transdermal patches of buflomedil hydrochloride, employing different ratios of pressure sensitive adhesives (PSAs) by solvent casting technique. The adhesive matrix-type transdermal patches were evaluated by their in vitro physicochemical properties such as thickness, moisture content, weight variation, drug content uniformity, etc. The effects of PSAs ratio, drug loading, and concentration of permeation enhancer were evaluated thoroughly. Ex vivo skin permeation studies with kinetic modeling of adhesive matrix patches were systematically evaluated. Based on the above observations, the best optimized buflomedil hydrochloride-loaded adhesive matrix-type transdermal patch was further characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction study, and differential scanning calorimetry analyses. Drug containing adhesive matrix patches showed sustained release property without showing any incompatibility in adhesive matrix system. Hence, adhesive matrix-type transdermal patches of buflomedil hydrochloride can be used as a potential carrier for sustained transdermal delivery of hydrophilic drugs like buflomedil hydrochloride. 相似文献
98.
盐酸克伦特罗完全抗原的合成及其偶联工艺的优化 总被引:1,自引:0,他引:1
为获取用于快速免疫分析的免疫抗原和包被抗原,本实验采用重氰化反应制备盐酸克伦特罗(Clenbuterolhydrochloride,CL)完全抗原,在强酸条件下CL先经重氮化,再与鸡卵清白蛋白(OVA)发生共价取代制备了盐酸克伦特罗包被抗原(OVA-CL),并以正交实验确定了共价取代反应的关键影响因素,进一步采用单因素实验确定了反应所需的最佳条件,并通过紫外扫描对制得的包被抗原进行了鉴定.结果表明,投料比例是盐酸克伦特罗完全抗原合成的关键因素,搅拌转速和反应时间也起着至关重要的作用.而且偶联反应在l h内基本完成,延长反应时间对提高产物偶联比影响不大.当投料比例为30:1,pH值约为8,低速搅拌状况下,包被抗原和免疫抗原的偶联比分别高达29:1和48:l,盐酸克伦特罗完全抗原合成条件的优化筛选取得了预期的效果. 相似文献
99.
Frank Marion E.; Formaker Bradley K.; Hettinger Thomas P. 《Canadian Metallurgical Quarterly》2003,117(2):228
The tastes of 100 mM sodium chloride (NaCl), 100 mM sucrose, and 1 mM quinine hydrochloride in mixtures were investigated in golden hamsters (Mesocricetus auratus) with a conditioned taste aversion (CTA) paradigm. CTAs, established in golden hamsters by injection of lithium chloride, were quantified as percent suppression of control 1-hr stimulus intake. CTAs for 10 of 15 stimulus pairs with common components symmetrically cross-generalized, suggesting that component qualities were recognized in binary and ternary mixtures. However, CTAs to quinine were hardly learned and were weakly expressed when quinine was mixed with NaCl, and generalizations from multiple to single stimuli were stronger than vice versa (i.e., asymmetric). The behaviors reflect peripheral inhibition and/or central mixture suppression. Nonetheless, components retain their distinct qualities in mixtures, suggesting that taste processing is analytic. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
丙酮与溴素(mol比为1:2.03)在冰醋酸存在下发生取代反应,分离提纯后得三种产物。经过IR和NMR分析,可确定主要产物为1,3-二溴丙酮。1,3-二溴丙酮为淡黄色液体(25℃),折光率n_D~(20)为1.553 2。1.3-二溴丙酮与六次甲基四胺成盐物分别在盐酸、乙醇中水解得淡黄色粉状固体。经过IR分析,证明生成物为1,3-二氨基丙酮盐酸盐。 相似文献