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以紫外光谱法研究了青霉素G钾盐(Pen-K)在十六烷基三甲基溴化铵(CTAB)胶束体系中的水解反应, 并探讨了水解反应机理.结果表明, CTAB胶束对Pen-K的水解具有抑制作用; Pen-K在CTAB胶束体系水解时,体系pH值的变化与在水中相似, 表明H+浓度对这种抑制作用影响较小.红外光谱和微极性研究表明,部分Pen-K钾盐定位于CTAB胶束栅栏层中, 增加了其稳定性. 相似文献
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β-CD对SDS胶束生成与特性的影响 总被引:1,自引:0,他引:1
通过胶束的扩散系数D、聚集数N和β-CD在SDS胶束与水连续相间的分配系数P的测定,研究了β-CD对SDS胶束特性的影响.结果表明,β-CD浓度较小时,随着β-CD的加入,其在SDS胶束相中的分配增大,胶束的扩散系数D与聚集数N均降低.β-CD浓度较大时,其在水连续相中的分配增加,对SDS胶束的扩散系数D与聚集数N的影响显著降低.SDS浓度小于第一CMC,β-CD与SDS单体形成1∶1的包合物;SDS浓度大于第一CMC,β-CD与SDS形成1:8的混合球形胶束. 相似文献
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流动注射化学发光法测定青霉素G钾 总被引:1,自引:0,他引:1
在甲醛的存在下,酸性KMnO4与青霉素G钾能够产生很强的化学发光,从而建立了KMnO4-甲醛-青霉素G钾化学发光体系来测定青霉素G钾.青霉素G钾的测定线性范围为2.0×10-7~1.0×10-5 g/mL,方法的检出限为1.4×10-7 g/mL,对4.0×10-7 g/mL的青霉素G钾进行11次平行测定,相对标准偏差为1.0%,用此法测定青霉素G钾取得了较好的结果. 相似文献
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以α-甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,β-内酰胺类抗生素青霉素V钾为模板,制备了分子印迹聚合物(MIP),通过紫外吸收光谱法研究发现模板分子与单体之间产生了氢键相互作用,二者的结合常数为2.889×109L3/mol3,化学配位比为3。通过吸附实验,探讨了印迹聚合物对模板分子的识别特性,结果印迹因子为2.31,最大表观结合量为8.63μg·mg-1,表明MIP对模板青霉素V钾有较强的特异识别性,为进一步将其应用于实际样品中抗生素的残留分析奠定了基础。 相似文献
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我们曾研究了黑皂膜的界面性质,为深入了解pH对偶氮苯类化合物在水溶液中及胶束表面上结构变化的影响,本文选用亮黄(BY)为谱学探针,仔细考察了其水溶液及溴化十六烷基三甲铵(CTAB)胶束溶液的共振Raman光谱,根据谱带指认,描述了由酸碱性导致的BY分子的结构变化,其中包括共振体间平衡和酸碱平衡。 相似文献
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火焰原子吸收光谱法间接测定青霉素V钾 总被引:3,自引:0,他引:3
基于青霉素V钾在酸性条件下的水解产物可与Pb2 + 形成沉淀 ,用火焰原子吸收光谱法测定沉淀中铅的含量 ,可间接测定药片中青霉素V钾的含量。在优化条件下 ,测定青霉素V钾的线性范围为 5 .15× 10 -5~ 4 .12× 10 -4mol/L ,线性回归方程为A =2 .4 2× 10 3 c - 0 .0 6 3 1,相关系数为 0 .999 1,检出限为 7.392× 10 -7mol/L ,测定结果的相对标准偏差为 0 .0 6 %~ 0 .6 9% ,回收率为 97.8%~ 10 2 .0 %。 相似文献
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反胶团相转移法提取青霉素G的研究 总被引:5,自引:1,他引:5
报道了非蛋白质类活性物质青霉素G在反胶团相转移提取中的特性和机理。结果表明,青霉素G在CTAB/正辛醇:氯仿(4:1,V/V)反胶团体系中的相转移提取为离子对静电作用与胶团溶解机理;在室温及pH值5~8的条件下,提取率在90%以上,且保持了青霉素的稳定性。 相似文献
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研究十六烷基三甲基溴化铵(CTAB)对DNA分子热稳定性的影响对于认识阳离子表面活性剂与DNA二者之间的相互作用具有重要的意义。用差示扫描量热法和变温紫外光谱法研究了CTAB对鲑鱼精DNA及降解的鲱鱼精DNA热稳定性的影响,发现CTAB使鲑鱼精DNA的热稳定性降低,但降低程度随CTAB浓度的增大而先增大后减小;CTAB使鲱鱼精DNA发生了两阶段熔解行为。 相似文献
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The effects of penicillin potassium salt (PenK) on the solubility, Krafft temperature TK, critical micelle concentration CMC of SDS micelle and the phase behavior of SDS/n-C5H11OH/H2O system were studied. The partial phase diagrams of SDS/PenK/H2O system at different temperatures were determined. The release amounts of PenK in SDS/n-C5H11OH/H2O system and the distribution coefficient of PenK between micelle and water were measured by UV-Vis spectroscopy. The results show that in the presence of PenK, the CMC of SDS was decreased while the TK of SDS was increased and the solubility of SDS in both water and SDS/n-C5H11OH/H2O oil in water (O/W) microemulsion was decreased, but increased in water in oil (W/O) microemulsion. SDS micelles and SDS/n- C5H11OH/H20 O/W microemulsion could accelerate the release rate of PenK. The addition of SDS and water could both increase the release rate of PenK, whereas the presence of n-C5H11OH reduced the release rate of PenK. The above results were related to the electrostatic repulsion between PenK and SDS. 相似文献
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Stefanie Breukers Christer L. Øpstad Hans‐Richard Sliwka Vassilia Partali 《Helvetica chimica acta》2009,92(9):1741-1747
The oft‐claimed ‘good’ water solubility of the food color norbixin ( 3 ) could not be confirmed. In contrast, the potassium salt 5 of norbixin formed suitable dispersions. The surface and aggregation properties of salt 5 were investigated and compared with other naturally occurring and synthetic hydrophilic carotenoids (Table). 相似文献
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Synthesis, Characterization and Properties of Tri-substitute Potassium Salt of Trinitrophloroglucinol 总被引:1,自引:0,他引:1
The title complex [K3(TNPG)·(H2O)2]n was synthesized by the reaction of the aqueous solutions of trinitrophlomglucinol (TNPG) with KHCO3. The complex was characterized by elemental analysis and FTIR spectroscopy, and its single crystal structure was determined by X-ray diffraction analysis. The structural analysis demonstrates that two different coordination modes of K cations [K(1) and K(2)] are around TNPG^3- anions in complex [Ka(TNPG)·(H2O)2]n, where the coordination numbers are eight. All K atoms coordinate with O atoms of phenolic hydroxyl group and nitro-group simultaneously. The thermolysis of the [Ka(TNPG) · (H2O)2]n has been investigated by using differential scanning calorimetry (DSC) and thermogravimetry-derivative thermogravimetry (TG-DTG) at a heating rate of 10 ℃/min. The thermal decomposition processes of the title complex were comprised of one endothermic dehydration stage and one exothermic decomposition stage in 270-320℃, and the final decomposition residue contained KNC. Impact and friction sensitivity results of the complex revealed its sensitive nature towards mechanical stimuli. The experiments verified that the complex has some characteristics of explosive. 相似文献
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钛酸镁钾具有优异的力学性能,被广泛用作各类高级轿车刹车片的摩擦材料。而材料的组成及形貌对刹车效果的影响很大,传统的合成工艺无法对其进行有效地控制。本文通过对煅烧工艺的优化,从而得到结晶度和形貌俱佳的钛酸镁钾片晶。以Mg(OH)_2、K_2CO_3和TiO_2为原料,加入KCl为熔盐,采用熔盐法合成钛酸钾镁片晶(KMTO)。利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)技术手段研究了煅烧工艺(升温速率、煅烧温度、保温时间)对钛酸钾镁片晶组成及形貌的影响,并对其反应机理进行了初步的探讨。结果表明,不同的煅烧工艺对熔盐法合成钛酸镁钾片晶的组成及形貌产生了显著的影响,以200℃/h升温至800℃后,再以100℃/h升温至1000℃,保温2 h,通过水洗干燥,即可得到结晶度较高、形貌比较均匀的K_(0.8)Mg_(0.4)Ti_(1.6)O_4片晶。 相似文献
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荧光和动态光散射方法研究两性表面活性剂胶束的聚集和相互作用 总被引:4,自引:0,他引:4
以芘为荧光探针、二苯酮为猝灭剂,利用荧光方法测定了两性表面活性剂N-十二烷基-N,N-二甲基氨基丙磺酸盐(DDAPS)胶束在不同温度和不同NaCl浓度下的聚集数。利用动态光散射方法得到了胶束的水力半径Rh.结果表明,DDAPS的胶束聚集数和Rh值随NaCl浓度的升高略有增大;随温度的升高而稍有下降。DDAPS胶束之间的作用力以排斥力为主。 相似文献