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31.
Copper (I) oxide nanocubes (Cu2O NCs) covered with cobalt oxide nanohexagons (Co3O4 NHs) were prepared through simple chemical method. Here, ascorbic acid is used as reducing and capping agent for the synthesis of nanocubes and nanohexagons. Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy‐dispersive X‐ray spectroscopy (EDX) and X‐ray diffraction spectroscopy (XRD) were employed to confirm the prepared nanocomposite. Cu2O NCs?Co3O4 NHs nanocomposite is drop cast on the glassy carbon electrode (GCE) for the fabrication of glucose sensor. The fabricated Cu2O NCs?Co3O4 NHs/GCE exhibited a better electrocatalytic activity towards the determination of glucose than that of individually fabricated Cu2O NCs and Co3O4 NHs modified GCE. Our finding exhibited a wide linear range from 1 μM to 5330 μM with LOD of 0.63 towards glucose. In addition, the sensor attained appreciable stability, repeatability and reproducibility. Practicality of the sensor was demonstrated in human serum samples. The main advantages of the fabricated sensor are simple, biocompatible, cost effective, fast response and highly stable electrode surface.  相似文献   
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An alternative synthetic route for the preparation of key intermediate synthons 7‐α‐bromoacetyl‐2‐diphenylaminofluorene (α‐BrDPAF‐H) and 7‐α‐bromoacetyl‐9,9‐dialkyl‐2‐diphenylaminofluorene (α‐BrDPAF‐Cn) was demonstrated. The latter reactions involved the first step of dialkylation of 2‐bromofluorene at C9 position of the fluorene moiety, the second step of a diphenylamino group attachment at C2 position of the resulting dialkylfluorene, and the third step of Friedel‐Craft acylation of α‐bromoacetyl group at C7 position of dialkylated diphenylaminofluorene. From the intermediates α‐BrDPAF‐H and α‐BrDPAF‐Cn, a series of C60keto‐DPAF nanostructures, such as the fullerene monoadducts C60(>DPAF‐H) and C60(>DPAF‐Cn), where n is 2, 4, or 10, were synthesized in a reasonable yield. Molecular mass ions of the dyads C60(>DPAF‐H), C60(>DPAF‐C2), C60(>DPAF‐C4), and C60(>DPAF‐C10) were clearly detected in positive ion matrix‐assisted laser desorption ionization mass spectrum (MALDI–MS) that confirmed the composition mass of each compound synthesized.  相似文献   
34.
VK Sharma  BK Chikara 《Pramana》1999,53(4):707-725
The d + d, t + p and h + n relative wavefunctions and their asymptotic normalizations are considered in the framework of the generator coordinate method (GCM) and compared with ATMS (amalgamation of two-body correlation into multiple scattering processes) method which used the realistic Reid soft core interaction. The asymptotic normalization of relative wavefunctions provide various coupling constants, the cluster probability amplitude (the so-called Z 1/2-factor) and matter RMS radii. These wavefunctions are also used to obtain 4He − dd, 4He − tp and 4He − hn vertex functions in the virtual decay of 4He. The extrapolation of vertex functions for negative values of q 2 upto the corresponding poles provide the vertex constants which are comparable with other estimates. It is noticed that in GCM the coupling constants C 2 for 4He − dd vertex is less than 2 as has been obtained in the forward dispersion relation technique.  相似文献   
35.
Long-term morpho-dynamics in special type of estuary   总被引:1,自引:0,他引:1  
Thousands of rocky hills and islands scattered in the Pearl River delta plain and the adjacent coastal waters in South China have been or will be acted as deposition nucleus during the evolution process of the delta. The Huangmaohai estuarine complex consists of two of the eight major outlets of the Pearl River estuarine system. Since sea level reached the present level approximately 6000 years ago, especially in the last 250 years, the Huangmaohai estuarine complex has progressed to the sea by filling up the sea inlets formed between these rocky islands and between mainland and islands. This 'filling up' process left deep imprints on the long-term mor-pho-dynamic equilibrium in the estuaries. The present paper reveals that the long-term mor-pho-dynamic relation originating from this 'filling up' process in the Huangmaohai estuarine complex is different from that in many coastal plain estuaries in several aspects: (1) longitudinal variation of estuary width, (2) longitudinal variation of tidal range, (3)  相似文献   
36.
Measurement of elastic and quasielastic reaction cross sections were done in 16O + 118Sn system at two different energies above the barrier. Attempts are being made to understand the results in the framework of coupled reaction channel model.  相似文献   
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