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本文研究了七个以反式二(二苯基膦吡啶)-三羰基铁为三齿配体的过渡金属双核配合物,将Jorgensen建议的处理电荷转移光谱的方法推广处理MMCT跃迁,通过光学电负性的计算取得金属-金属成键的证据。由Raman光谱羰基伸缩振动频率的蓝移进一步支持这类化合物中存在金属-金属成键相互作用的推断。  相似文献   
64.
Alloyed ternary CdS(1-x)Se(x) nanowires were synthesized by template-assisted electrodeposition, in which the ratio of S to Se in the nanowires was controlled by adjusting the relative amounts of the starting materials. Higher-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) showed that the alloyed ternary CdS(1-x)Se(x) nanowires are highly crystalline, and no phase-separated Cd was observed in these nanowires. Optical measurements indicated that the band-gap engineering can be realized in these CdS(1-x)Se(x) nanowires through modulating the composition of S and Se. With broadly tunable optical and electrical properties, these alloyed nanowires could be used in color-tuned nanolasers, biological labels, and nanoelectronics.  相似文献   
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本文合成了Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Cu(Ⅱ)大环配合物及其溴碘加成物,研究了远红外和Raman光谱,对MN4局部进行了伸缩振动的简正坐标分析,求得了各化合物的键角和伸缩力常.通过Raman光谱初步确定了溴碘的存在形式.对溴碘加成物的叠层结构和各化合物的成键进行了讨论.  相似文献   
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对HDEHP(H2B2)和HEH/EHP(H2L2)混合萃取剂在硫酸介质中萃取稀土元素(La,Nd,Sm,Gd)的机制进行了研究。研究表明,在水相平衡pH=2.0时,混合萃取剂萃取这几种元素的协萃系数分别为:1.96(La),3.52(Nd),5.96(Sm),5.71(Gd),并且协萃系数随水相平衡pH的升高而增加。利用斜率法分别确定了单一萃取剂HDEHP和HEH/EHP以及混合萃取剂HDEHP HEH/EHP在硫酸体系中萃取稀土元素的配合物结构式分别为RE(SO4)xH2x(HB2)3,RE(SO4)xH2x(HL2)3以及RE(HB2)2(HL2)。计算了反应的平衡常数及形成常数并确定了反应机制为阳离子交换反应。  相似文献   
67.
采用原子吸收分光光度法测定87例中风患者血清中Ca、Mg、Zn、Cu、Fe含量,并与正常组作对比。结果表明:中风患者Zn、Fe降低,而Mg、Cu增高,Zn/Cu比值降低(P<0.05~0.01);而两组血清Ca无统计学上的差别(P>0.50)。  相似文献   
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The facile one-pot preparation of hydrophobic cellulose nanocrystals (CNCs) from wood pulpboard in an ionic liquid is reported in the present paper. This process employed a so-called amorphous cellulose solvent system capable of dissolving the majority of the amorphous regions in cellulose while maintaining the crystalline domains essentially intact, and consisting of tetrabutylammonium acetate with dimethylacetamide. These solvents were mixed at a mass ratio of 1:9 in conjunction with acetic anhydride to prepare CNCs via surface acetylation. The rod-like morphology and nanometer-scale dimensions of the resulting CNCs were ascertained by atomic force microscopy and transmission electron microscopy. Successful surface acetylation while maintaining an intact crystalline core was confirmed by Fourier transform infrared, 13C CP/MAS NMR and X-ray photoelectron spectroscopy in addition to X-ray diffraction. Finally, the thermal stability and hydrophobic behavior of the hydrophobic CNCs were characterized using thermal gravimetric analysis and water contact-angle measurements, respectively.  相似文献   
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Meditinib (ME) is a novel tyrosine kinase inhibitor used as an antichronic myeloid leukemia drug. A simple, sensitive and specific LC/MS/MS method was developed and validated for the analysis of ME and its metabolite demethylation meditinib (PI) in monkey plasma using naltrexone as the internal standard. Sample preparation involved protein precipitation with methanol. The analysis was carried out on an Agilent C8 column (3.5 µm, 2.1 × 50 mm). Elution was achieved with a mobile phase gradient varying the proportion of a water solution containing 0.1% formic acid (solvent A) and a 0.1% formic acid in methanol solution (solvent B) at a flow rate of 300 μL/min. The method had a linear calibration curve over the concentration range of 2–1000 ng/mL for ME and 2–1000 ng/mL for PI. The lower limits of quantification of ME and PI were 2 and 2 ng/mL, respectively. The intra‐ and inter‐day precision values were <15% and accuracy values were within ±10.0%. The mean recoveries of ME and PI from plasma were >85%. The assay has been successfully used for pharmacokinetic evaluation of ME and PI using the monkey as an animal model, and those data are reported for the first time. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
70.
A highly novel and direct synthesis of benzoxazinones was developed via Cp*Co(III)-catalyzed C–H activation and [3 + 3] annulation between sulfoxonium ylides and dioxazolones. The reaction is conducted under base-free conditions and tolerates various functional groups. Starting from diverse readily available sulfoxonium ylides and dioxazolones, a variety of benzoxazinones could be synthesized in one step in 32%-75% yields.  相似文献   
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