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91.
Characteristics of charge traps in TlInS2 single crystals are investigated by the use of thermally stimulated current (TSC) technique. The TSC spectra of the sample from 80 K to 300 K are recorded at a constant heating rate. The spectra reveal that there are several trapping levels associated with the complex structure of overlapping peaks. The experimental results indicate that the traps in TlInS2 associated with the spectra in the measuring range of temperature obey the monomolecular (first order) kinetics. Thus, the spectra are resolved into first order shaped peaks by the use of computerized best fit procedure. The trapping parameters; such as the energy depth, temperature dependent frequency factor and capture cross section, together with concentrations of the corresponding six discrete levels are computed. These centers all having low capture cross sections with strong temperature dependence are found to be at the energies of 0.11 eV, 0.22 eV, 0.25 eV, 0.26 eV, 0.29 eV and 0.30 eV with high concentrations of 6.6 × 1016, 2.0 × 1017, 3.3 × 1017, 9.6 × 1016, 2.3 × 1017 and 4.0 × 1017 cm?3, respectively. 相似文献
92.
This paper studies the importance of corrections that account for the presence of walls on the forces act- ing on nanoparticles during their transport in microchannels.Theoretical and experimental investigations have reported anisotropic and hindered motion of nanoparticles near a microchannel wall. To investigate the influence of the near-wall effects, various conditions were examined. In particular, computer simu- lations were performed with and without the near-wall correction of forces. The corresponding capture efficiency and the average penetration of the captured nanoparticles were compared, and the importance of the near-wall corrections was assessed. Effects were evaluated for the nanoparticle diameter, the chan- nel width, the channel length, and the pressure gradient. The results indicate that the inclusion of wall effects is crucial for the analysis of nanoparticle transport in microchannels. 相似文献
93.
In this paper, we study the joint user assignment and power allocation for the defined utility function (central cell throughput) maximization in massive Multiple Input-Multiple Output (MIMO) cellular system coexistence with Wireless Fidelity (WiFi) network. Firstly, the power allocation of problem is formulated as a convex optimization. Unfortunately, the formulated problem has not a closed-form solution. For solving the mentioned problem, it is converted to three sub-problem based on the number of lemmas that are expressed. Due to two of these problems remain difficult to solve, this two sub-problem are relaxed. The Ellipsoid algorithm is an iterative algorithm that used for solving of the relaxed problems. In the following, joint user assignment and power allocation will be addressed, in which two approaches are proposed for solving. In the first approach, we propose an iterative algorithm that user assignment problem and power allocation problem are solved in each iteration. In the second approach, at first, users are assigned to licensed and unlicensed bands, then for the obtained arrangement, the power allocation problem is solved. The simulation results showed that the proposed algorithms are significantly close to the benchmark methods. 相似文献
94.
Immobilized enzymatic reactors recently have drawn much attention because of the striking advantages, such as high substrate turnover rate and ease in coupling with the separation and detection systems. Carrier materials, which have great effects on the development of the immobilized enzymatic reactors, have always being the focus of study. In this paper, the contributions, mainly in the last 5 years, on the enzymatic reactors and their applications in proteome study are reviewed, with some newly developed inorganic and organic carriers for enzyme immobilization described in details. Moreover, the hyphenation of immobilized enzymatic reactors with the separation and identification systems is also summarized. By reviewing these achievements, it could be seen that enzymatic reactors have very bright future, especially in proteome analysis. 相似文献
95.
Lianbing Ren Yunchun LiuMingming Dong Zhen Liu 《Journal of chromatography. A》2009,1216(47):8421-8425
Boronate affinity chromatography is an important tool for specific isolation of cis-diol-containing compounds such as glycoproteins, RNA and carbohydrates. Boronate functionalized monolithic capillaries have been recently developed for specific capture of cis-diol-containing small biomolecules, but the apparent hydrophobicity of the columns prevents them from specific capture of glycoproteins. In this paper, a hydrophilic boronate affinity monolithic capillary was prepared by in situ free radical polymerization, using 4-vinylphenylboronic acid (VPBA) and N, N′-methylenebisacrylamide (MBAA) as functional monomer and cross-linker, respectively. The prepared poly(VPBA-co-MBAA) monolithic capillary exhibited uniform open channel network and high density of accessible boronic acid. Due to the utilization of hydrophilic cross-linker, the prepared column was hydrophilic, allowing for specific capture of glycoproteins. 相似文献
96.
97.
Among features observed in polyethylene-based materials under high fields, packet-like space charge are frequently reported but without complete theory explaining their formation and propagation. The present contribution reports transient dynamics of packet-like space charge in low-density polyethylene (LDPE) under multi-field coupling conditions based on pulsed electro-acoustic (PEA) method. The measurements were carried out under −125 kV/mm at 20 °C, 40 °C, and 60 °C. Space charge results reveal systematic occurrence of positive packet-like space charge in all samples generated at the anode and then moved toward the cathode. It is observed that higher temperatures contribute to the migration of packet-like space charge and field distortion. Based on the detailed injection model of packet-like space charge, it is shown that electrode injection plays a major role in the formation of positive packet-like space charge, the total amount and depth not only depend on the temperature, but also the negative charges dynamics. Packet-like space charge phenomena at different temperatures still feature NDM relationship with the nonlinear increase of migrate velocity as the rise of temperature. 相似文献
98.
99.
Xiaogang Chen Zonglong Wang Deyi Chen 《International Journal of Infrared and Millimeter Waves》2008,29(4):424-431
The effects of direct current (dc) bias-drifting on radio on fiber (RoF) links are quantitative investigated and simulated.
Single sideband (SSB) modulation and carrier suppressed double sideband (CS-DSB) modulation RoF links are considered, power
variation of targeted signal and harmonic suppression on account for bias-drifting are calculated and evaluated. Our results
suggest that power variation can be maintained within 1.1 dB with dc bias drift ε less than 5% in the SSB modulation RoF link
and the degradation of harmonic suppression is evident with ε exceed 2% in the CS-DSB modulation RoF link. 相似文献
100.
A pursuit-evasion differential game with bounded controls and prescribed duration is considered. The evader has two possible dynamics, while the pursuer dynamics is fixed. The evader can change the dynamics once during the game. The pursuer knows the possible dynamics of the evader, but not the actual one. The optimal pursuer strategy in this game is obtained. It is robust with respect to the control of the evader, the order of its dynamics and the time of the mode change. The capture conditions of the game are established and the pursuer capture zone is constructed. An illustrative example of the game is also presented. 相似文献