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61.
王恒  赵洁  陈志伟  何品刚  方禹之 《色谱》2008,26(6):740-743
建立了同时测定含脂羊毛中除虫脲和杀铃脲的反相高效液相色谱方法。样品用正己烷-乙醚混合溶剂提取,经凝胶渗透色谱柱和固相萃取柱净化后,采用反相高效液相色谱-二极管阵列检测器检测,外标法定量。除虫脲和杀铃脲分别在0.41~41 mg/L和0.38~38 mg/L范围内线性关系良好,相关系数分别为0.9996和0.9999。最低检出限:除虫脲为0.22 mg/kg,杀铃脲为0.18 mg/kg;最低定量限:除虫脲为0.73 mg/kg,杀铃脲为0.60 mg/kg。在添加水平为0.76~10.25 mg/kg的除虫脲和杀铃脲时,平均加标回收率为86.3%~96.7%,相对标准偏差为4.2%~8.7%。该方法杂质干扰小、回收率高、重现性好,能够对含脂羊毛中除虫脲和杀铃脲残留量进行准确的定性定量分析。  相似文献   
62.
原油是最复杂的化学体系之一,人们对原油这种复杂的胶态分散体及其稳定性的研究兴趣与日俱增,尤其是与石油稳定性密切相关的沥青质超分子聚集体。但人们对形成沥青质超分子聚集体的主要作用力长期以来颇有争议。本文重点介绍了石油组分及其模型化合物在溶液中形成超分子聚集体的超分子化学作用研究进展。通过实验方法和理论计算证明沥青质聚集体是沥青质分子间通过氢键、π-π堆积、偶极-偶极相互作用等多种分子间弱相互作用力协同作用形成的热力学稳定结构;合成具有沥青质结构特点的纯化合物,研究它们在溶液中的行为,是提高对沥青质在液态相中自缔合行为认识的有效方法;结合现阶段的研究状况,对石油组分模型化合物的超分子化学作用研究的发展前景进行了展望。  相似文献   
63.
Lignin‐grafted copolymers, namely lignin‐graft‐poly(methyl methacrylate‐co‐butyl acrylate) (lignin‐g‐P(MMA‐co‐BA)), are synthesized via “grafting from” atom transfer radical polymerization (ATRP) with the aid of lignin‐based macroinitiators. By manipulating the monomer feed ratios of MMA/BA, grafted copolymers with tunable glass transition temperatures (−10–40 °C) are obtained. These copolymers are evaluated as sustainable thermoplastic elastomers (TPEs). The results suggest that the mechanical properties of these TPEs lignin‐g‐P(MMA‐co‐BA) copolymers are improved significantly by comparing with those of linear P(MMA‐co‐BA) copolymer counterparts, and the elastic strain recovery is nearly 70%. Lignin‐g‐P(MMA‐co‐BA) copolymers exhibit high absorption in the range of the UV spectrum, which might allow for applications in UV‐blocking coatings.

  相似文献   

64.
沈桂荣  傅恩生 《光学学报》1993,13(2):61-164
报道了研制的激光束二维强度分布测量装置,实现了从红外到可见的激光束二维强度分布测量,给出直观的激光束远场立体花样和平面分布等高能量图,进一步用该装置测量出激光能量,文章最后给出了标定方法和结果.  相似文献   
65.
徐光辉[1,第六章§1]讨论了成批服务系统M/M[r]/1,并在limPj(t)=Pj>0假设下,求出马氏过程N(t)的平稳分布{Pi},李文琦等在[2,P1688]指出[1.P218—219]给出的关于limPj(t)=Pj>0的证明是不准确的,并利用Foster判别法给出N(t)的遍历性的严格证明。本文指出N(t)的遍历性可由Pij(△t)的表达式及Takacs[4,P94定理2]推出。  相似文献   
66.
The diagnostic system for two dimension(2-D)intensity distribution of laserbeam is a measuring instrument for many parameters of laser beam.2-D intensity distributionplot of laser beam is obtained by the two dimension scanning mirror which is controlled by amicrocomputer to scan the laser beam on a detector.Many parameters of laser beam such asthe isointensity distribution plot,the beam diameter,the beam waist diameter,the laser pow-er,the diverge angle and the beam brightness,are given by means of the microcomputer pro-cessing the data measured.Theoretical analysis of beam parameter transform is given.  相似文献   
67.
食品中碘的光谱电化学法测定   总被引:5,自引:1,他引:4  
本文研究了用光谱电化学法测定食品中的碘,探讨了最佳的测定条件,用于海带,海带表层盐及模拟碘盐中碘的测定,结果满意,回收率高,抗干扰力强,操作快捷,方法简单易行。  相似文献   
68.
Tong L  Wang Y  Xiong J  Cui Y  YigangZhou  Yi L 《Talanta》2008,76(1):80-84
Eucommia ulmodies Oliver (E. ulmodies) has been used as herbal medicine for thousands years in China. The selection of the control substances and their fingerprints of this plant medicine were investigated by using high performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). The gradient elution mode was applied in chromatographic separation, and the data was analyzed by "Computer Aided Similarity Evaluation" software to compare the similarity of the E. ulmodies from different habitats. Low similarity was found in the samples from nonadjacent provinces, while high similarity was obtained in those from the adjacent provinces. The LC-MS fingerprints of E. ulmodies showed the main active constituents and could be used for its original identification and quality evaluation.  相似文献   
69.
Thin film transistors (TFTs) with zirconium‐doped indium oxide (ZrInO) channel layer were successfully fabricated on a flexible PEN substrate with process temperature of only 150 °C. The flexible ZrInO TFT exhibited excellent electrical performance with a saturation mobility of as high as 22.6 cm2 V–1 s–1, a sub‐threshold swing of 0.39 V/decade and an on/off current ratio of 2.5 × 107. The threshold voltage shifts were 1.89 V and ?1.56 V for the unpassivated flexible ZrInO TFT under positive and negative gate bias stress, respectively. In addition, the flexible ZrInO TFT was able to maintain the relatively stable performance at bending curvatures larger than 20 mm, but the off current increased apparently after bent at 10 mm. Detailed studies showed that Zr had an effect of suppress the free carrier generation without seriously distorting the In2O3 lattice. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   
70.
A novel and facile magnetic deep eutectic solvents (DES) molecularly imprinted polymers (MIPs) for the selective recognition and separation of Bovine hemoglobin (BHb) was prepared. The new-type DES was adopted as the functional monomer which would bring molecular imprinted technology to a new direction. The amounts of DES were optimized. The obtained magnetic DES-MIPs were characterized with fourier transform infrared spectrometry (FT-IR), thermogravimetric analysis (TGA), field emission scanning electron microscope (FESEM), dynamic light scattering (DLS), elemental analysis and vibrating sample magnetometer (VSM). The results suggested that the imprinted polymers were successfully formed and possessed a charming magnetism. The maximum adsorption capability (Qmax) and dissociation constant (KL) were analyzed by Langmuir isotherms (R2 = 0.9983) and the value were estimated to be 175.44 mg/g and 0.035 mg/mL for the imprinted particles. And the imprinted particles showed a high imprinting factor of 4.77. In addition, the magnetic DES-MIPs presented outstanding recognition specificity and selectivity so that it can be utilized to separate template protein from the mixture of proteins and real samples. Last but not least, the combination of deep eutectic solvents and molecular imprinted technology in this paper provides a new perspective for the recognition and separation of proteins.  相似文献   
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