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71.
Hyun‐Woo Shim Ah‐Hyeon Lim Jae‐Chan Kim Gwang‐Hee Lee Prof. Dong‐Wan Kim 《化学:亚洲杂志》2013,8(11):2851-2858
A phase‐pure MnWO4‐based nanocomposite, MnWO4@MWCNTs (MWCNTs=multiwalled carbon nanotubes), was successfully synthesized through a simple hydrothermal reaction at 180 °C by adjusting the pH of the precursor medium. The resulting nanocomposite maintains the original flowerlike morphology of MnWO4 with hierarchical structures composed of numerous single‐crystalline nanorods that drive growth preferentially along the [001] direction. The growth mechanism for the flowerlike formations is also discussed. In addition, the Li electroactivity of pure MnWO4 and MnWO4@MWCNTs electrodes was investigated. As an anode for Li‐ion batteries, the MnWO4@MWCNTs nanocomposite showed enhanced electrochemical performance in reversible Li storage relative to that shown by bare MnWO4 electrodes, including a high capacity of 425 mAh g?1 and superior rate performance. This performance can be attributed to the synergistic effect of the nanocomposite combined with the MWCNTs, which provide efficient electron transport in their role as a conductor. 相似文献
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73.
Morpholine amide intermediates, which are easily prepared by aminolysis of various esters with diisobutyl(morpholino)aluminum, react with organolithium and reducing agents (DIBALH or LDBMA) without isolation of the aminolysis intermediates to give ketones in 83–95% yields and aldehydes quantitatively. 相似文献
74.
Cover Picture: Long‐Lived Trifluoromethanide Anion: A Key Intermediate in Nucleophilic Trifluoromethylations (Angew. Chem. Int. Ed. 43/2014)
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75.
Suparno Mukhopadhyay Hilmi Luş Ah Lum Hong Raimondo Betti 《Journal of sound and vibration》2012,331(17):3961-3975
It is of interest to the modal testing and health monitoring community to quantify how an error in any identified mode shape propagates to the identified flexibility matrix. Here this problem is investigated in a probabilistic framework. The approach followed involves deriving analytical expressions to track how errors, due to random deviations between identified and “true” mode shapes, propagate to the Modal Assurance Criterion (MAC) and the Coordinate Modal Assurance Criterion (COMAC) values as well as the estimated flexibility matrix. The comparison of the expected values and variances of these errors identifies the inconsistency between the magnitude of errors in the MAC and COMAC values and the identified flexibility matrix. The analytical results are further validated via Monte Carlo simulations. Finally, two mode shape comparison criteria, termed as the Flexibility Proportional Modal Assurance Criterion (FPMAC) and the Flexibility Proportional Coordinate Modal Assurance Criterion (FPCOMAC), are proposed. These new criteria aim to mimic the expected error in the predicted flexibility matrix in a direct comparison of the identified and “true” mode shapes, and hence they can be used to complement MAC and COMAC in interpreting the analysis results. 相似文献
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78.
Md. Abdul Aziz Kyungmin Jo Jeong‐Ah Lee Md. Rajibul Haque Akanda Daekyung Sung Sangyong Jon Haesik Yang 《Electroanalysis》2010,22(22):2615-2619
We herein report an amphiphilic polymer‐, carboxylated multiwalled carbon nanotube (CNT)‐, silane polymer‐, and streptavidin‐modified indium tin oxide (ITO) electrode that allows low nonspecific binding and efficient immobilization of DNA, along with good electrocatalytic activities and low background‐current levels. The low nonspecific binding results from the well‐covering of the CNT and ITO surface with the amphiphilic polymer and silane polymer, as well as the poly(ethylene glycol) groups of the polymers. The streptavidin for DNA immobilization is covalently attached to the carboxylic acid groups of the amphiphilic polymer and CNT. A low surface coverage of CNT on the ITO electrode provides the good electrocatalytic activities and low background‐current levels. The fabricated electrode enables us to achieve a detection limit of 100 pM in DNA detection. 相似文献
79.
Jongmee Lee Cheol Min ParkKyeong Ah Kim Chang Hee LeeJae Woong Choi 《Magnetic resonance imaging》2010
Purpose
The purpose of this study was to describe magnetic resonance (MR) findings of focal eosinophilic liver disease using gadoxetic acid (Gd-EOB-DTPA).Materials and Methods
Nineteen patients (M:F=14:5; age range, 26–66 years; mean age, 50 years) with 35 focal eosinophilic liver lesions were included after reviewing the medical records of 482 patients who underwent Gd-EOB-DTPA-enhanced MR imaging (MRI) on a 3.0-T unit between April 2008 and June 2009. The diagnosis of focal eosinophilic liver disease was established by means of percutaneous liver biopsy or surgery and consistent clinical findings. Two radiologists retrospectively reviewed MR images with consensus. Margin, shape and distribution of the lesions were analyzed. We also evaluated signal intensity of focal hepatic lesions on T1- and T2-weighted images and patterns of enhancement in dynamic contrast study.Results
The mean diameter of the lesions was 1.7 cm (range, 0.7–6.1 cm). Most of the focal eosinophilic liver lesions [n=31/35 (88.6%)] had poorly defined margins. They were usually isointense or slightly hypointense [n=34/35 (97.2%)] on T1-weighted images and hyperintense [n=32/35 (91.4%)] on T2-weighted images. Dynamic study showed enhancement (rim or homogeneous) on the arterial phase [n=21/35 (60%)] and hypointensity on the late venous phase [n=31/35 (88.6%)]. All the lesions were hypointense on the hepatobiliary phase images.Conclusion
Focal eosinophilic liver lesions tend to be hyperintense on the arterial phase and hypointense on the late venous phase during dynamic study of Gd-EOB-DTPA-enhanced MRI. Although these findings mimic other focal hepatic lesions, poorly defined margins of the lesions and peripheral eosinophilia might help distinguish focal eosinophilic liver disease from other hepatic lesions. 相似文献80.
Toy AA Chaffey-Millar H Davis TP Stenzel MH Izgorodina EI Coote ML Barner-Kowollik C 《Chemical communications (Cambridge, England)》2006,(8):835-837
Thioketones are demonstrated to be suitable agents for controlling free radical polymerization processes: the polymerizations carry (pseudo) living characteristics indicating that the control process is induced by a persistent radical effect. 相似文献