固相萃取-高效液相色谱法测定动物尿样中的莱克多巴胺

莱克多巴胺（ractopamine）是一种新型的β-肾上腺素兴奋剂,我国农业部、卫生部、国家药品监督管理局在2002年联合下发的176号公告中已经明确将其列入禁用药品名单。目前,文献报道的莱克多巴胺的检测方法很少,特别是国内还未见文献报道。由于莱克多巴胺在动物体内代谢较快,因而药物往往以原形的形式从体内排出。检测动物尿样具有快速、准确等特点,建立动物尿样中的莱克多巴胺的检测方法可以对畜产品生产过程中使用莱克多巴胺的现象进行有效的监控。因此,探索动物尿样中莱克多巴胺的检测方法具有非常重要的理论意义和实际价值。本文建立了动物尿样中莱克多巴胺残留量的高效液相色谱（HPLC）测定方法,样品处理简单,灵敏度高。     

维生素A衍生物合成工艺的改进

维生素A衍生物合成工艺的改进;多双键烷基膦衍生物;Wittig-Horner反应     

物理实验数据处理中的一些问题的探讨

针对当前大学物理实验教学中关于数据处理的一些问题进行了探讨。提出了测量值与测量结果这两个词的不同。对于有效数字位数的保留进行了系统性的分析。指出了数据修约中所存在的一些不恰当之处。认为实验教学中宜考虑测量次数对实验结果的影响。简述了置信概率、概率型式、标准不确定度及扩展不确定度等问题的相互联系。     

Plasma electrolytic oxidation of AZ91D magnesium alloy in biosafety electrolyte for the surgical implant purpose

Plasma electrolytic oxidation (PEO) of AZ91D magnesium alloy in biosafety electrolyte was studied. The prepared PEO coating and its stability in the simulated body fluid (SBF) were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), potentio-dynamic polarization, electrochemical impedance spectroscopy (EIS) and immersion test. The SEM results show that a kind of smooth, compact and well adhesive PEO coating is prepared in the proposed biosafety electrolyte. The electric analytical results show that the corrosion resistance of the PEO coating is excellent even in harsh environment. Immersion test shows that the PEO coating is stable enough in the SBF solution. The weight loss, the average corrosion rate and the pH variation of the PEO treated magnesium alloy are far lower than the untreated ones. From these highly positive results, the proposed PEO process is promising in the treatment of the surgical magnesium alloy materials.     

Structure and Fluorescence Property of a 2D Macrometallacycle Supramolecular Network [Zn2(2-mBIM)2(SUC)2]n

A zinc(Ⅱ) coordination polymer [Zn2(2-mBIM)2(SUC)2]n (1, 2-mBIM = bis(2-methylimidazo-1-yl) methane, SUC = succinate anion) has been synthesized and characterized by X-ray diffraction. Complex 1 crystallizes in the triclinic space group P1 with a = 9.4871(8), b = 12.9789(5), c = 14.0230(5), α = 90.474(1), β = 90.3560(10), γ = 109.691(1)°, V = 1529.94(15)3 , Z = 2, Dc = 1.553 mg/m3 , μ = 1.63 mm-1 , F(000) = 736, the final R = 0.0645 and wR = 0.0951 for 4067 observed reflections with I > 2σ(I). Each Zn atom was coordinated by two individual 2-mBIM ligands in a cis-conformation and two monodentate coordinated succinate anions in a gauche conformation, resulting in the formation of a two-dimensional supramolecular network containing a cationic 16-membered macrometallacycle and a 28-membered macrometallacycle. The result also indicates that the conformation of the ligands has a strong influence on the structure of the supramolecular network.     

Effects of cyclodextrin-modified polycarboxylate superplasticizers on the dispersion and hydration properties of cement paste

Abstract

A new series of poly (AA-co-β-CD-A-co-TPEG) (PACDs) copolymers were prepared by the copolymerization of a novel monovinyl β-cyclodextrin monomer (β-CD-A), acrylic acid and isoprenyl oxy polyethylene glycol (TPEG-2400), which could be used as superplasticizers and shown excellent dispersion ability. Therefore, this work mainly investigated the adsorption behavior, dispersing properties as well as hydration behavior of cement pastes. Optical microscopy was employed to describe dispersing performance. X-ray diffraction (XRD) and TGA/DTG were utilized to account for the cement hydration process. We found that the PACDs with β-CD-A exhibited outstanding dispersion ability. In addition, the performances of the PACDs were monitored by evaluating the setting time and fluidity of the cement paste. The results clearly shown that the setting time was longer and slump loss was smaller than that of PACD₀ that without β-CD-A. Therefore, PACDs with the proper content of β-CD pendants had excellent performances due to the steric hindrance of the CD moieties.     

超高效液相色谱-质谱结合主成分分析方法研究制川乌配伍前后的肠内菌代谢差异

利用超高效液相色谱-质谱联用( UPLC-MS)技术结合主成分分析方法研究制川乌单煎液、制川乌与白芍、制川乌与防己共煎液在大鼠肠内菌中的代谢差异。采用SIMCA-P软件,以肠内菌代谢后乌头类生物碱的相对含量为变量进行主成分( PCA)分析。在主成分得分图中,制川乌单煎液与制川乌-白芍、制川乌-防己共煎液均可以明显区分,说明制川乌单煎液与制川乌-白芍、制川乌-防己共煎液的肠内菌生物转化存在显著差异。通过主成分分析载荷图及独立样本t检验,从制川乌-白芍组得到7种差异显著的标志物,从制川乌-防己组得到6种标志物,其中制川乌-白芍组有4种标志物经肠内菌代谢后含量高于制川乌组,而制川乌-防己组有1种化合物含量高于制川乌组,两组中其它标志物含量低于制川乌组。这些标志物可能是制川乌配伍前后药效差异的物质基础。     

CO2相干激光轮廓成像研究

本文以自制CO_2相干激光成像的实验系统,成功地实现了相干激光的彩色轮廓成像。     

沉淀介质对共沉淀法制备（Bi，Pb）2223先驱粉的影响

本文利用物理化学原理对改进的共沉淀法和传统的共沉淀法所使用的介质进行了对比研究．通过比较PH值在以水为介质的传统共沉淀法和改进的以乙醇为介质的共沉淀法的化学计量比的不同影响，我们发现传统共沉淀法不能找到合适的PH值范围来使各种金属离子完全共沉淀，也就难以维持原始的化学计量比，而改进的共沉淀法有很宽的PH值范围（PH=3～7．4），能使所要沉淀的各种金属离子完全共沉淀并维持原始的化学计量比．对改进的共沉淀法制备的前驱粉经过X光衍射分析显示，其相组成合适．扫描电镜分析显示前驱粉完全满足制备超导（Bi，Pb）2223带材的需要．