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2.
Manika Chaudhary Milan Singh Ashwani Kumar Yogendra K. Gautam Anil K. Malik Yogesh Kumar Beer Pal Singh 《Ceramics International》2021,47(2):2094-2106
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
3.
Robert Groth Luke T. Cravigan Sadegh Niazi Zoran Ristovski Graham R. Johnson 《Journal of the Royal Society Interface》2021,18(178)
The airborne dynamics of respiratory droplets, and the transmission routes of pathogens embedded within them, are governed primarily by the diameter of the particles. These particles are composed of the fluid which lines the respiratory tract, and is primarily mucins and salts, which will interact with the atmosphere and evaporate to reach an equilibrium diameter. Measuring organic volume fraction (OVF) of cough aerosol has proved challenging due to large variability and low material volume produced after coughing. Here, the diametric hygroscopic growth factors (GF) of the cough aerosol produced by healthy participants were measured in situ using a rotating aerosol suspension chamber and a humidification tandem differential mobility analyser. Using hygroscopicity models, it was estimated that the average OVF in the evaporated cough aerosol was 0.88 ± 0.07 and the average GF at 90% relative humidity (RH) was 1.31 ± 0.03. To reach equilibrium in dry air the droplets will reduce in diameter by a factor of approximately 2.8 with an evaporation factor of 0.36 ± 0.05. Hysteresis was observed in cough aerosol at RH = ∼35% and RH = ∼65% for efflorescence and deliquescence, respectively, and may depend on the OVF. The same behaviour and GF were observed in nebulized bovine bronchoalveolar lavage fluid. 相似文献
4.
The crystallization process of hexagonal boron nitride in the presence of copper has been investigated. The positive effect of copper on the crystallinity of boron nitride was observed in the three studied systems of: nitrided boron, nitrided boron–carbon, and previously prepared turbostratic boron nitride. However, the presence of copper hindered the formation of boron carbonitride and produced graphite and boron nitride phases separately. Poor crystallinity was found as a conditio sine qua non for the existence of such a compound. Well-crystallized boron nitride had a very low spacing parameter 0.3328 nm and a regular hexagonal shape. 相似文献
5.
Apparent carbon aromaticities, fa, of some asphaltenes have been measured by n.m.r. in solution and compared with those obtained by the CP/MAS technique on solid samples. The aromaticities were also measured for several Alberta plains coals. From the 1H solution spectra and 13C solid nmr spectra of asphaltenes, some of their skeletal features, not obtainable from solution spectra only, have been suggested. 相似文献
6.
John R. Clem Zhidong Hao Ljiljana Dobrosavljević-Grujić Zoran Radović 《Journal of Low Temperature Physics》1992,88(3-4):213-219
We present a generalized variational model of an isolated vortex, valid in the anisotropic case when the external magnetic field is along one of the symmetry directions. We discuss the effects of the field anisotropy on the core and magnetic pinning of individual vortices. 相似文献
7.
8.
Zoran Ognjanovi? Zoran Markovi? Miodrag Ra?kovi? Dragan Doder Aleksandar Perovi? 《Annals of Mathematics and Artificial Intelligence》2012,65(2-3):217-243
The aim of the paper is to present a sound, strongly complete and decidable probabilistic temporal logic that can model reasoning about evidence. The formal system developed here is actually a solution of a problem proposed by Halpern and Pucella (J Artif Intell Res 26:1–34, 2006). 相似文献
9.
A case of using the Semantic Interoperability Framework for custom orthopedic implants manufacturing
Milan Zdravković Miroslav Trajanović Miloš Stojković Dragan Mišić Nikola Vitković 《Annual Reviews in Control》2012,36(2):318-326
The efficiency and effectiveness of the daily practice in orthopedic surgery depend on the availability, interoperability and unique access to a wide set of information, related to the patient’s medical record and diagnosis, domain knowledge and available resources and staff. The most important of the tangible resources, needed for the therapeutic or preventive actions are orthopedic implants. In some cases, the implants may be highly complex and customized products, which need to be manufactured (assembled) on basis of the above information in a shortest possible timeframe. In this paper, the case of the custom orthopedic implants manufacturing is described from the perspective of the collaborative enterprising, with special consideration of the interoperability issues of the involved enterprise collaboration. It is shown how the previously developed Semantic Interoperability Framework can be used to improve the efficiency of the manufacturing and other relevant processes. 相似文献
10.
This paper proposes a system for the early automatic recognition of health problems that manifest themselves in distinctive
form of gait. Purpose of the system is to prolong the autonomous living of the elderly at home. When the system identifies
a health problem, it automatically notifies a physician and provides an explanation of the automatic diagnosis. The gait of
the elderly user is captured using a motion-capture system, which consists of body-worn tags and wall-mounted sensors. The
positions of the tags are acquired by the sensors and the resulting time series of position coordinates are analyzed with
machine-learning algorithms in order to recognize a specific health problem. Novel semantic features based on medical knowledge
for training a machine-learning classifier are proposed in this paper. The classifier classifies the user’s gait into: 1)
normal, 2) with hemiplegia, 3) with Parkinson’s disease, 4) with pain in the back and 5) with pain in the leg. The studies
of 1) the feasibility of automatic recognition and 2) the impact of tag placement and noise level on the accuracy of the recognition
of health problems are presented. The experimental results of the first study (12 tags, no noise) showed that the k-nearest
neighbors and neural network algorithms achieved classification accuracies of 100%. The experimental results of the second
study showed that classification accuracy of over 99% is achievable using several machine-learning algorithms and 8 or more
tags with up to 15 mm standard deviation of noise. The results show that the proposed approach achieves high classification
accuracy and can be used as a guide for further studies in the increasingly important area of Ambient Assisted Living. Since
the system uses semantic features and an artificial-intelligence approach to interpret the health state, provides a natural
explanation of the hypothesis and is embedded in the domestic environment of the elderly person; it is an example of the semantic
ambient media for Ambient Assisted Living. 相似文献