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111.
Cation-vacancy induced intrinsic magnetism in GaN and BN is investigated by employing density-functional theory based electronic structure methods. The strong localization of defect states favors spontaneous spin polarization and local moment formation. A neutral cation vacancy in GaN or BN leads to the formation of a net moment of 3 muB with a spin-polarization energy of about 0.5 eV at the low density limit. The extended tails of defect wave functions, on the other hand, mediate surprisingly long-range magnetic interactions between the defect-induced moments. This duality of defect states suggests the existence of defect-induced or mediated collective magnetism in these otherwise nonmagnetic sp systems.  相似文献   
112.
As the application of electrocatalyst continues to expand, envisaging the hidden mechanisms occurring at various length scale affecting the catalytic efficiency became important. To enhance the stability of electrocatalyst and reduce the cost, it is of paramount importance to reveal the active site's dynamics (using in situ techniques for getting the real-time information) which directly affect the reactions such as oxygen evolution reaction, hydrogen evolution reaction, and so on. Since such reactions are crucial for many engineering and scientific applications, in situ characterization techniques are required, which could capture such reactions happening at a different length and time scale. This article analyzes the recent progress made in the field of electrocatalyst's characterization using in situ neutron techniques. The article also paves the future path and has delineated the future challenges involved in multiscale correlative techniques (e.g., neutron techniques in the combination of synchrotron or microscopic techniques) used for getting the multiscale (atomic to micrometer range) mechanistic information about the electrocatalyst's working and degradation.  相似文献   
113.

In the present work, radon concentrations were measured in surface and underground water samples in Faridabad District of Southern Haryana, India using an active radon monitor based on alpha scintillation technique and results have been inter-compared. The average radon concentration in the underground water samples was observed to be 4 times higher than in the surface water samples. The estimated annual effective dose varied from 5.7 to 58.5 μSvy?1 with an average of 24.2 μSvy?1 for underground water samples and 1.1 to 12.5 μSvy?1 with an average of 6.7 μSvy?1 for surface water samples. The estimated annual effective dose for both type of samples was found to be less than 0.1 mSvy?1, which is the safe limit as suggested by World Health Organisation and EU Council.

  相似文献   
114.
Journal of Thermal Analysis and Calorimetry - In order to decrease the energy consumptions in energy conversion devices, boiling heat transfer augmentation is one of the important research...  相似文献   
115.
116.
Post-translational methylation, discovered more than half a century ago, encodes information in the form of a structural modification on a peptide or protein. The addition of a CH3 group is one of the most subtle covalent modifications that exist in biology. In spite of this, recent years have revealed the many profound functional effects that arise from protein methylation in the cell. In an effort to open the doors to new assays and detection methods that would enable new basic and applied research into methylation pathways, chemical agents that can recognise and bind to methylated sites are now being pursued. In this review, we describe the supramolecular approaches to the recognition of methylated amino acids, peptides and proteins that have arisen in the last few years.  相似文献   
117.
Pool boiling heat transfer performances of Cu-Al2O3-coated copper surfaces have been studied experimentally for its potential use in heat transfer applications. In the present study, a two-step electrochemical deposition method is examined. This method provides an easy control on surface properties such as porosity and coating thickness. The deposition method is studied carefully and responsible surface morphology parameters are reported. After performing the pool boiling experiments on coated surfaces with DI water, the maximum critical heat flux of 1800 kW/m2 and heat transfer coefficient of 193 kW/m2 K, which are 68% and 260% higher than that of bare surface, respectively.  相似文献   
118.
ABSTRACT

Wireless sensor networks (WSNs) play a vital role in present-day world, which are being used in different types of applications and occupy an important part in networking domain. The main objective of WSNs is to sense and collect the information from a given area of interest and provide the gathered data to the sink. WSN comprises of number of sensor nodes with batteries of limited energy for communication and computational activities, which are not possible to recharge the batteries after their deployment in the region of interest. Therefore, saving battery energy and utilising the limited power to the optimum level for extending network lifetime became the main factor of WSN. Hence, optimum cluster head (CH) selection will make the network to support longer lifetime and balanced energy consumption during its lifetime. Our proposed protocol selects the optimum CH and found out to be more efficient than the existing low energy adaptive clustering hierarchy. The simulated output shows better network lifetime and in some other performance metric.  相似文献   
119.
120.
A perchlorate ligand in the rare mu4-1,1,2,2 binding mode is seen for the first time as the sole support for the assembly of two cationic [Cu II 2L]+ fragments (H3L = a dinucleating ligand) in the formation of a magnetically-exchanged tetranuclear cluster.  相似文献   
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