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971.
972.
973.
A. Shailos M. El Hassan C. Prasad J. P. Bird D. K. FerryL. -H. Lin N. Aoki K. Nakao Y. OchiaiK. Ishibashi Y. AoyagiT. Sugano 《Superlattices and Microstructures》2000,27(5-6)
We present evidence for a re-entrant metal–insulator transition that arises in quantum dot arrays as the gate voltage is used to sweep their density of states past the Fermi level. The form of the temperature variation of the conductance observed in these arrays can be accounted for using a functional form derived from studies of the metal–insulator transition in two dimensions, although the values obtained for the fit parameters suggest that the behavior we observe here may be quite distinct to that found in two dimensions. 相似文献
974.
Lithium trifluoromethane-sulfonate (Li-TFMS:CF3SO3Li) irradiated by γ-rays showed an electron spin resonance (ESR) powder spectrum having the rhombicg-factor ofg xx = 2.0259 ± 0.0005,g yy = 2.0112 ± 0.0005 andg zz = 2.0025 ± 0.0005 and a triplet hyperfine coupling constant ofA xx/gβ= 0.8 ± 0.15 mT.A yy andA zz are not obtained because of the broadened spectrum. The energy levels,g-factor,A xx/gβ and optical absorption spectrum of several conceivable radicals such as C⋅F2SO3Li, CF3-S-O⋅ and CF3-S-O-O⋅ have been calculated by softwares MOPAC-V2 and Gaussian-98 based on ROHF (Restricted Hatree-Fock for open shell molecule). The most probable radical was ascribed to CF3-SO⋅ from both calculated and experimental results. The response to γ-ray dose and the thermal stability have been studied in addition to the effect of UV illumination for possible use of the signal intensity in ESR dosimetry. The obtained number of free radicals per 100 eV (G-value) was 1.23 ± 0.40. 相似文献
975.
A sensitive and selective electrochemical sensor for the determination of glutathione(GSH) was developed using a modified multiwall carbon nanotube paste electrode with 3,4 dihydroxy cinnamic acid as a mediator.This modified electrode showed very high electrocatalytic activity for the anodic oxidation of GSH.Under the optimized conditions,the electrocatalytic peak current showed a linear relationship with GSH concentration in the range of 0.5-400.0 μmol/L with a detection limit of 0.1 μmol/L GSH.The relative standard deviations for seven successive assays of 5.0 and 25.0 μmol/L GSH were 2.2% and 2.7%,respectively.The modified electrode was used for the determination of GSH compounds in real urine samples. 相似文献
976.
Sami Ullah Khan Hassan Waqas Taseer Muhammad Muhammad Imran Malik Zaka Ullah 《理论物理通讯》2020,72(10):105001-11
The current article investigates the impact of the bioconvection in an unsteady flow of magnetized Cross nanofluid with gyrotactic microorganisms and activation energy over a linearly stretched configuration. The analysis has been performed by utilizing the realistic Wu's slip boundary and zero mass flux conditions. The effects of nonlinear thermal radiation and the activation energy are also addressed. The governing flow equations are deduced to a dimensionless form by considering suitable transformations which are numerically targeted via a shooting algorithm. The physical visualization of each physical parameter governing the flow problem has been displayed graphically for distribution of velocity, temperature, concentration and motile microorganisms. The numerical treatment for the variation of skin friction coefficient, local Nusselt number, local Sherwood number and motile density number is performed in tabular forms. 相似文献
977.
Khizar Hayat Mahmood Hassan Akhtar Awais Siddique Saleemi Hafiz Badaruddin Ahmad Naeem Akhtar 《Electroanalysis》2020,32(8):1664-1670
Herein, we report the development of a robust, sensitive, and selective non‐enzymatic electrochemical sensor for the detection of hydrogen peroxide (H2O2). The novel BA modified CN‐dot wrapped Cu2O‐nano‐frogspawn (FS@CN‐dot) sensor probe demonstrated a catalytic property towards H2O2 that allowed the highly sensitive electrochemical detection at a low reduction potential. The as prepared CN‐dot wrapped Cu2O hetero‐structured nanocomposite was analyzed using surface analysis methods to confirm the morphology, crystallinity, and oxidation states of various constituents and dopant elements. Further, the morphological analysis of the Cu2O nanoparticles revealed that the Cu2O retains frogspawns‐liked structure. Under the optimized experimental conditions, the sensor showed a wide dynamic range of H2O2 from 0.5 μM to 9 mM with a detection limit (LD) of 1.2±0.1 nM. The designed sensing probe showed good stability, high sensitivity, and selectivity even in the presence of potential interfering molecules. To check the reliability of the fabricated sensor in biomedical applications, the proposed sensing probe was successfully applied to monitor H2O2 in saliva of a gum‐diseased patient. To the best of our knowledge, this report is the first of its kind not only because of its novel construction style in terms of CN source, but also in terms of real sample applicability as well. 相似文献
978.
Fathy Hassan Masuki Kawamoto Krishnachary Salikolimi Daisuke Hashizume Takuji Hirose Yoshihiro Ito 《Tetrahedron letters》2018,59(2):99-102
An operationally simple ring closure of racemic 1,1′-bi-2-naphthol (BINOL) yielded the heterocyclic aromatic compound 7H-dibenzo[c,g]carbazole (DBC). This one-pot method gave a good conversion and is suitable for gram-scale synthesis. DBC derivatives have high thermal durability, amorphous and crystalline structures with unique morphological properties, and semi-conducting behavior with potential applications in organic electronics. 相似文献
979.
In the present work, the separations of calixarene derivatives have been investigated using both high-performance liquid chromatography (HPLC) and nonaqueous capillary electrophoresis (NACE) techniques. HPLC-1 method with LC-318 (pore size = 300 Å) column and MeCN mobile phase was optimized for the separation of calixarenes. At the flow-rate of 1 ml/min p-nitrocalix[6]arene, calix[4]arene and calix[6]arene could be well baseline and symmetrically separated within 5 min. For the separation of p-tert-butylcalix[n]arenes (n = 4, 6, 8), HPLC-2 and NACE methods have been optimized. The optimal conditions in HPLC-2 method included NH2 column and MeCN mobile phase, and p-tert-butylcalix[n]arenes (n = 4, 6, 8) were baseline separated within 10 min at 0.8 min/min. The optimal conditions for NACE method employed MeCN-H2O (8:2, v/v) as the nonaqueous medium and 120 mM Tris/HCl (pH 9.0) as the buffer, and p-tert-butylcalix[n]arenes (n = 4, 6, 8) were successfully baseline resolved within 16 min. With the detection at 280 nm, the calibration lines were linear in the ranges of 1-200 μg/ml for calixarene derivatives by HPLC-1 and HPLC-2 methods, and of 2.5-200 μg/ml for p-tert-butylcalix[n]arenes (n = 4, 6, 8) by NACE method, respectively. The detection limits (S/N = 3) and recoveries ranged from 0.5 to 1.4 μg/ml and from 98.1 to 102.4% by both HPLC-1 and HPLC-2 methods, and from 1.3 to 2.0 μg/ml and from 97.9 to 105.1% by NACE method, respectively. The intra-day reproducibility of the methods was determined with satisfactory results. The proposed HPLC and NACE methods were accurate and reproducible, and could be utilized to separate and determine calixarene derivatives. 相似文献
980.
In this work, we define cumulative residual q-Fisher (CRQF) information measures for the survival function (SF) of the underlying random variables as well as for the model parameter. We also propose q-hazard rate (QHR) function via q-logarithmic function as a new extension of hazard rate function. We show that CRQF information measure can be expressed in terms of the QHR function. We define further generalized cumulative residual divergence measures between two SFs. We then examine the cumulative residual q-Fisher information for two well-known mixture models, and the corresponding results reveal some interesting connections between the cumulative residual q-Fisher information and the generalized cumulative residual divergence measures. Further, we define Jensen-cumulative residual (JCR-) measure and a parametric version of the Jensen-cumulative residual Fisher information measure and then discuss their properties and inter-connections. Finally, for illustrative purposes, we examine a real example of image processing and provide some numerical results in terms of the CRQF information measure. 相似文献