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31.
片剂中红霉素的二次微分简易示波伏安法测定   总被引:4,自引:0,他引:4  
根据在 pH=10.0的NaOH -H3BO3-KCl支持电解质溶液中 ,红霉素在二次微分简易示波伏安图阴极支 -1.55V(vsSCE)处产生一灵敏峰的示波特性 ,建立了测定药品中红霉素含量的二次微分简易示波伏安法 ;校正曲线的线性范围为2.5×10-6~4.8×10-5 mol/L,相关系数为0.9994 ,检出限为1.2×10-6 mol/L;对8.000×10 -6mol/L红霉素进行7次测定的RSD为1.9 % ,样品的平均回收率为99 % ;该法的特点为仪器简单、简便快速、无需通氮除氧。  相似文献   
32.
AIM:To prepare polylactiv acid microspheres of Erythromycin for Lung targeting.METHEDS:The orthogonal test design was used to optimize the technology of preparation.The character of the microspheres,drug release in vitro,stabiligy and tissue distribution were examined. RESULTS:The Erythromycin polylatic acid microspheres was regular in its morphology.Drug was enveloped in microspheres but not physically mixed with PDLLA.The average particle size was 11.65μm with over 94% of the microspheres being in the range of 5-20μm;The drug loading and the incorporation efficiency were 18% and 60% respectively.The microspheres were stable for three month at 4℃ and room temperature.The in vitro release properties could be expressed by the Higuchi′s equation:y=28.067+3.8515t^1/2(r=0.9834).Comparing with injection,the drug in microspheres was more concentrated in lung tissue.CONLUSION:Erythromycin polylactic acid microspheres showed significant sustained release and lung targeting.  相似文献   
33.
Six molecularly imprinted polymers (MIPs) of erythromycin (ERY) were prepared by noncovalent bulk polymerization using methacrylic acid (MAA) as the functional monomer. On the basis of binding analysis, the MIPs with 1:2 optimum ratio of template to MAA were selected for subsequent scanning electron microscopy and Brunauer–Emmett–Teller analyses, which indicated that the MIPs had more convergent porous structures than the nonimprinted polymers. The equilibrium binding experiments showed that the binding sites of MIPs were heterogeneous, with two dissociation constants of 0.005 and 0.63 mg mL−1, respectively. Furthermore, the performance of the MIPs as solid-phase extraction (SPE) sorbents was evaluated, and the selectivity analysis showed that the MIPs could recognize ERY with moderate cross-reactivity for other macrolides. The overall investigation of molecularly imprinted SPE for cleanup and enrichment of the ERY in pig muscle and tap water confirmed the feasibility of utilizing the MIPs obtained as specific SPE sorbents for ERY extraction in real samples. Figure Schematic diagram of the preparation and application of the erythromycin imprinted molecularly imprinted polymers Suquan Song and Aibo Wu contributed equally to this work.  相似文献   
34.
琥乙红霉素与茜素的荷移反应及其测定   总被引:3,自引:0,他引:3  
孙曙光 《光谱实验室》2004,21(6):1115-1118
琥乙红霉素与茜素在水 -乙醇介质中反应 ,生成电荷转移络合物 ,最大吸收波长为 5 46 nm,表观摩尔吸光系数为 9.91× 10 3 L· mol-1·cm-1。以等摩尔连续变换法和斜率比法测得荷移络合物的组成比为1∶ 1,稳定常数是 1.6× 10 4。浓度在 0— 80 mg/ L范围内服从比耳定律。 6次测定结果的相对标准偏差为1.4 1%。测定了琥乙红霉素样品中有效成分的含量 ,与文献结果基本吻合 ,回收率在 97.0 %以上  相似文献   
35.
Using a laser monitoring observation technique, the solubility of erythromycin acetone solvate in binary acetone + water solvent mixtures was measured by a synthetic method at temperatures ranging from 298.00 K to 323.00 K and at atmosphere pressure. The results of these measurements were correlated by the combined nearly ideal binary solvent CNIBS/Redlich–Kister equation and the modified Apelblat equation, respectively. For the solubility data studied, the CNIBS/Redlich–Kister equation was found to provide a more accurate mathematical representation of the experimental data.  相似文献   
36.
琥乙红霉素与水杨基荧光酮(SAF)在乙醇溶液中发生荷移反应,荷移络合物在522nm处有最大吸收,表观摩尔吸光系数ε为8.5×103L.mol^-1.cm^-1,荷移络合物的组成比为1∶1,稳定常数是105.2,药物浓度在1.724—129.3mg/L范围内服从比耳定律。当琥乙红霉素的浓度为68.96mg/L时,8次测定结果的相对标准偏差为0.52%。测定了琥乙红霉素片剂中有效成分的含量,并与药典法比较,结果基本吻合,回收率在98.3%以上。  相似文献   
37.
本文利用4-(1'-四氢吡咯)吡啶(PPY)及聚乙烯吡啶(PVP)复合催化剂催化合成了11,2',4'-三-0酰化红霉素衍生物,与传统方法相比,该法具有简单、快速、收率高等优点。一些影响素及反应机理被讨论,目标物收率为90%以上。  相似文献   
38.
Erythromycin is a mixture of macrolide antibiotics produced by Saccharopolyspora erythreas during fermentation. A new method for the analysis of erythromycin by liquid chromatography has previously been developed. It makes use of an Astec C18 polymeric column. After validation in one laboratory, the method was now validated in an interlaboratory study. Validation studies are commonly used to test the fitness of the analytical method prior to its use for routine quality testing. The data derived in the interlaboratory study can be used to make an uncertainty statement as well. The relationship between validation and uncertainty statement is not clear for many analysts and there is a need to show how the existing data, derived during validation, can be used in practice. Eight laboratories participated in this interlaboratory study. The set-up allowed the determination of the repeatability variance, s(2)r and the between-laboratory variance, s(2)L. Combination of s(2)r and s(2)L results in the reproducibility variance s(2)R. It has been shown how these data can be used in future by a single laboratory that wants to make an uncertainty statement concerning the same analysis.  相似文献   
39.
红霉素分子印迹二维光子晶体水凝胶传感器的研究   总被引:1,自引:0,他引:1  
以红霉素为印迹分子,聚苯乙烯二维光子晶体为模板,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸甲酯为交联剂,2,2-二乙氧基苯乙酮为引发剂,紫外光引发聚合,在甲醇-乙酸(9∶1, V/V)中洗脱印迹分子,得到能够特异性识别红霉素的分子印迹二维光子晶体水凝胶.通过测试德拜环直径变化,研究了此水凝胶在红霉素溶液中的响应性能.实验结果表明,当红霉素的浓度从0增加到1×10-6 mol/L时,德拜环直径增加6 mm, 相应的晶格间距减小30 nm.此外,水凝胶在1×10-6 mol/L红霉素的类似物罗红霉素、琥乙红霉素溶液中,德拜环直径仅分别增加1.5和2.0 mm,表明此光子晶体水凝胶具有良好的选择性,有望用于红霉素低成本的简易检测.  相似文献   
40.
高效液相色谱法测定红霉素、甲红霉素和罗红霉素的研究   总被引:6,自引:0,他引:6  
建立了高效液相色谱-荧光法同时测定红霉素、甲红霉素、罗红霉素的方法。该方法以9-芴代甲氧苯酰氯(FMOC-CL)为衍生试剂,以V(乙腈)∶V(磷酸二氢钾)=3∶1为反应体系,于50℃反应1 h。液相色谱分析条件为:Extend-C18柱(4.6 mm i.d.×150 mm),乙腈-25 mmoL磷酸二氢胺(pH 7)为流动相,梯度淋洗;柱温30℃,流速1.5 mL/min,激发波长255 nm、发射波长315 nm。线性范围分别为红霉素0.5~100μg、甲红霉素0.5~100μg、罗红素0.1~150μg。检出限为红霉素1μg/mL、甲红霉素1μg/mL、罗红霉素0.25μg/mL。加标回收率为90%~97%,相对标准偏差为3.5%~7.9%。  相似文献   
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