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101.
The current research work presents a facile and cost–effective co-precipitation method to prepare doped (Co & Fe) CuO and undoped CuO nanostructures without usage of any type of surfactant or capping agents. The structural analysis reveals monoclinic crystal structure of synthesized pure CuO and doped-CuO nanostructures. The effect of different morphologies on the performance of supercapacitors has been found in CV (cyclic voltammetry) and GCD (galvanic charge discharge) investigations. The specific capacitances have been obtained 156 (±5) Fg?1, 168(±5) Fg?1 and 186 (±5) Fg?1 for CuO, Co-doped CuO and Fe-doped CuO electrodes, respectively at scan rate of 5 mVs?1, while it is found to be 114 (±5) Fg?1, 136 (±5) Fg?1 and 170 (±5) Fg?1 for CuO, Co–CuO and Fe–CuO, respectively at 0.5 Ag-1 as calculated from the GCD. The super capacitive performance of the Fe–CuO nanorods is mainly attributed to the synergism that evolves between CuO and Fe metal ion. The Fe-doped CuO with its nanorods like morphology provides superior specific capacitance value and excellent cyclic stability among all studied nanostructured electrodes. Consequently, it motivates to the use of Fe-doped CuO nanostructures as electrode material in the next generation energy storage devices.  相似文献   
102.
Neural Computing and Applications - The identification of water stress is a major challenge for timely and effective irrigation to ensure global food security and sustainable agriculture. Several...  相似文献   
103.
X-linked retinitis pigmentosa (XLRP) results from mutations in at least two different loci, designated RP2 and RP3, located at Xp11.3 and Xp21.1, respectively. The RP3 gene was recently isolated by positional cloning, whereas the RP2 locus was mapped genetically to a 5-cM interval. We have screened this region for genomic rearrangements by the YAC representation hybridization (YRH) technique and detected a LINE1 (L1) insertion in one XLRP patient. The L1 retrotransposition occurred in an intron of a novel gene that consisted of five exons and encoded a polypeptide of 350 amino acids. Subsequently, nonsense, missense and frameshift mutations, as well as two small deletions, were identified in six additional patients. The predicted gene product shows homology with human cofactor C, a protein involved in the ultimate step of beta-tubulin folding. Our data provide evidence that mutations in this gene, designated RP2, are responsible for progressive retinal degeneration.  相似文献   
104.
A mathematical model to represent turbulent fluid flow and mixing in continuous casting tundishes has been developed. The model involves solution of the three-dimensional turbulent Navier-Stokes equation, turbulence being modeled by the so-calledK-ε, two-equation model. Fluid flow parameters and residence time distribution has been predicted in a tundish of rectangular cross section. The model is later extended to predict fluid flow in typical industrial tundishes where walls are not vertical, but rather slightly inclined from the vertical. This results in an interresting variation in fluid flow, which may have important technological implications. The theoretical predictions are compared with measurements obtained in water models. The detailed understanding of the hydrodynamics of the tundish flow can be used to optimize their design for steel cleanliness. YOUDUO HE (on leave from Boutao Institute of Iron and Steel Technology, People's Republic of China) Research Associate  相似文献   
105.
X-ray holography is a new method of structure determination based on measurement of interference of a known reference wave with an unknown object wave (containing information on atomic sites scattering the reference wave) so that phase information is preserved. Unlike X-ray diffraction, it does not demand for translational periodicity in the material. It is based on the idea similar to that of optical holography and has been tested on crystals, quasicrystals, thin films and doped semiconductors for their structure determination. In order to analyse potentials and limitations of this technique, we have carried out theoretical simulation studies on simple structures. In this paper we describe the basic algorithm of hologram generation and reconstruction of atomic positions from generated data. We illustrate this technique using Fe (bcc) single crystal as sample case to demonstrate its capabilities and limitations. Simulations were carried out on the Cu (fcc) structure and on complex structure such as the Al-Pd-Mn quasicrystal. Technical issues such as low signal to noise ratio, twin image problem etc have been discussed briefly to emphasize the need for high intensity X-ray source such as synchrotron for experiments and proper reconstruction algorithm. Finally the scope and potential of this technique have been discussed.  相似文献   
106.
The fill area primitive of GKS (Graphical Kernel System)1 is one of the more powerful features which differentiates it from earlier device independent graphics software and systems. Its specification is extremely general in the form of a closed boundary, possibly self-intersecting, and whose interior can be filled in a variety of styles. However a complete implementation of this primitive is very complex. It is difficult to find a single graphics workstation incorporating this primitive in hardware or firmware. Most GKS implementations will have to include software for simulating the appearance of this primitive on the commonly available displays and hard-copy graphics devices. Correct and efficient algorithms are necessary for developing this software. Because of the generality many of the existing algorithms are not directly applicable. In this paper we describe:
1. a new algorithm for clipping a fill area polygon, using what we have named as the Bridge Technique.
2. implementation of a plane sweep algorithm, by Nievergelt and Preparata,2 for solid filling and hatching, particularly applicable to vector devices.
3. extension of the plane sweep algorithm for filling with any given pattern on raster as well as vector devices.
The algorithms have been designed to work for all special cases as well. In fact they have been implemented having in mind the fill area set primitive of GKS-3D extension.3 All these algorithms have been very successfully implemented in a commercially available GKS implementation, namely indoGKS.  相似文献   
107.
Wireless Personal Communications - Adaptive transmission strategies for cognitive radio sensor network provide flexibility to the nodes based on data packets. In this paper, an optimum transmission...  相似文献   
108.
Journal of Electronic Materials - This paper presents a systematic study of Al0.23Ga0.77N/GaN/AlxGa1?xN double-heterojunction high-electron-mobility transistors (DH-HEMTs) with a boron-doped...  相似文献   
109.
Human’s decision making is not necessarily always planned; their unplanned behaviour—determined by natural personality traits—also contributes to the decision making process. In this study, we investigate factors related to planned and unplanned behaviour to understand why people share political content in online social media. Based on an online survey of 257 social media users, our results demonstrate that the factors representing both planned (i.e., perceived social recognition and altruistic motivation) and unplanned behaviour (i.e., extroversion and impulsiveness) affect people’s political content sharing behaviour. Our study understands that sharing political content is not like sharing other forms of content such as tourist attractions—the former can provoke serious punishment in some countries. Accordingly, trait impulsiveness is negatively associated with political content sharing behaviour. We also found that collective opinion moderates people’s planned behaviour, but not their unplanned behaviour. In other words, personality traits are unaffected by others’ opinions, but traits that humans can control can be shaped by others’.  相似文献   
110.
In this paper, a simple and robust approach for flame and fire image analysis is proposed. It is based on the local binary patterns, double thresholding and Levenberg–Marquardt optimization technique. The presented algorithm detects the sharp edges and removes the noise and irrelevant artifacts. The autoadaptive nature of the algorithm ensures the primary edges of the flame and fire are identified in the different conditions. Moreover, a graphical approach is presented which can be used to calculate the combustion furnace flame temperature. The various experimentations are carried out on synthetic as well as real flame and fire images which validate the efficacy and robustness of the proposed approach.  相似文献   
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