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71.
A first-order theory is presented for the calculation of the effects of compositional variation on the transport properties of glass melts. The theory is based upon the modified Enskog theory applied to the high-temperature expansion of the free energy. The theory is applied to a simple two-component glass system and compared to experimental and previous theoretical results. 相似文献
72.
Routing in ad hoc networks is a complicated task because of many reasons. The nodes are low-memory, low-powered, and they cannot maintain routing tables large enough for well-known routing protocols. Because of that, greedy forwarding at intermediate nodes is desirable in ad hoc networks. Also, for traffic engineering, multi-path capabilities are important. So, it is desirable to define routes at the source like in source based routing (SBR) while performing greedy forwarding at intermediate nodes.We investigate trajectory-based routing (TBR) which was proposed as a middle-ground between SBR and greedy forwarding techniques. In TBR, source encodes trajectory to be traversed and embeds it into each packet. Upon the arrival of each packet, intermediate nodes decode the trajectory and employ greedy forwarding techniques such that the packet follows its trajectory as much as possible.In this paper, we address various issues regarding implementation of TBR. We also provide techniques to efficiently forward packets along a trajectory defined as a parametric curve. We use the well-known Bezier parametric curve for encoding trajectories into packets at source. Based on this trajectory encoding, we develop and evaluate various greedy forwarding algorithms 相似文献
73.
Functional,porous metal-organic frameworks(MOFs)have attracted much attention as a very flexible class of crystalline,porous materials.For more advanced applications that exploit photophysical properties,the fabrication of hierarchical assemblies,including the creation of MOF/MOF heterointerfaces,is important.For the manufacturing of superstructures with length scales well beyond that of the MOF pore size,layer-by-layer(Ibl)methods are particularly attractive.These allow the isoreticular approach to be extended to superstructures with micrometer length scales,a range that is not accessible using conventional MOF design.The Ibl approach further substantially extends the compositional diversity in MOFs.At the same time,the favorable elastic properties of MOFs allow for heteroepitaxial growth,even in the case of lattice misfits as large as 20%.While the MOF-on-MOF approach to designing multicomponent superstructures with synergistic multifunctionality can also be realized with sophisticated solvothermal synthesis schemes,the Ibl(or liquid-phase epitaxy)approach carries substantial advantages,in particular when it comes to the integration of such MOF superstructures into optical or electronic devices.While the structure vertical to the substrate can be adjusted using the Ibl method,photolithographic methods can be used for lateral structuring.In this review,we will discuss the Ibl liquid-phase epitaxy approach to growing surface-anchored MOF thins films(SURMOFs)as well as other relevant one-pot synthesis methods for constructing such hierarchically designed structures and their emerging applications. 相似文献
74.
Maurya Ritesh Singh Neha Jindal Tanu Pathak Vinay Kumar Dutta Malay Kishore 《Multimedia Tools and Applications》2022,81(10):13713-13729
Multimedia Tools and Applications - An electromagnetic field radiations (EMF) emanating from the cell phones affect the brain and other organs in living organisms. Therefore, the objective of the... 相似文献
75.
76.
Integrating nanophotonics with electronics could enhance and/or enable opportunities in areas ranging from communications and computing to novel diagnostics. Light sources and detectors are important elements for integration, and key progress has been made using semiconducting nanowires and carbon nanotubes to yield electrically driven sources and photoconductor detectors. Detection with photoconductors has relatively poor sensitivity at the nanometre scale, and thus large amplification is required to detect low light levels and ultimately single photons with reasonable response time. Here, we report avalanche multiplication of the photocurrent in nanoscale p-n diodes consisting of crossed silicon-cadmium sulphide nanowires. Electrical transport and optical measurements demonstrate that the nanowire avalanche photodiodes (nanoAPDs) have ultrahigh sensitivity with detection limits of less than 100 photons, and subwavelength spatial resolution of at least 250 nm. Crossed nanowire arrays also show that nanoAPDs are reproducible and can be addressed independently without cross-talk. NanoAPDs and arrays could open new opportunities for ultradense integrated systems, sensing and imaging applications. 相似文献
77.
Masaki M Aritake K Tanaka H Shoyama Y Huang ZL Urade Y 《Molecular nutrition & food research》2012,56(2):304-308
Crocus sativus L. (saffron) has been traditionally used for the treatment of insomnia and other diseases of the nervous systems. Two carotenoid pigments, crocin and crocetin, are the major components responsible for the various pharmacological activities of C. sativus L. In this study, we examined the sleep-promoting activity of crocin and crocetin by monitoring the locomotor activity and electroencephalogram after administration of these components to mice. Crocin (30 and 100 mg/kg) increased the total time of non-rapid eye movement (non-REM) sleep by 60 and 170%, respectively, during a 4-h period from 20:00 to 24:00 after its intraperitoneal administration at a lights-off time of 20:00. Crocetin (100 mg/kg) also increased the total time of non-REM sleep by 50% after the administration. These compounds did not change the amount of REM sleep or show any adverse effects, such as rebound insomnia, after the induction of sleep. 相似文献
78.
Ritesh Bansal Chander Kumar Nagpal Shailender Gupta 《Multimedia Tools and Applications》2018,77(6):6799-6835
Commonly used security mechanisms such as cryptography and steganography suffer from weaknesses when used in a standalone manner. Extra efforts in the form of additional permutations/diffusions etc. result in higher ciphering/deciphering time complexity. Thus, there is a requirement for a security mechanism(s) which can provide adequate security without putting a considerable burden on ciphering/deciphering time complexity. This paper is an effort in this direction. The paper proposes a hybrid mechanism that employs chaotic based encryption scheme to encrypt data and an improved Bit-Plane Complexity Segmentation Steganography algorithm to embed the data. The proposed mechanism uses two new complexity measures to differentiate between noisy regions and simple ones appropriately. The scheme was implemented in MATLAB, and the simulation results show that the proposed mechanism has high embedding capacity, high security with a moderate decrease in PSNR value and is computationally fast. 相似文献
79.
80.
Yoan Cherasse Hitomi Saito Nanae Nagata Kosuke Aritake Michael Lazarus Yoshihiro Urade 《Molecular nutrition & food research》2015,59(10):2087-2093
Zinc is an essential trace element for humans and animals, being located, among other places, in the synaptic vesicles of cortical glutamatergic neurons and hippocampal mossy fibers in the brain. Extracellular zinc has the potential to interact with and modulate many different synaptic targets, including glutamate and GABA receptors. Because of the central role of these neurotransmitters in brain activity, we examined in this study the sleep‐promoting activity of zinc by monitoring locomotor activity and electroencephalogram after its administration to mice. Zinc‐containing yeast extract (40 and 80 mg/kg) dose dependently increased the total amount of nonrapid eye movement sleep and decreased the locomotor activity. However, this preparation did not change the amount of rapid eye movement sleep or show any adverse effects such as rebound of insomnia during a period of 24 h following the induction of sleep; whereas the extracts containing other divalent cations (manganese, iron, and copper) did not decrease the locomotor activity. This is the first evidence that zinc can induce sleep. Our data open the way to new types of food supplements designed to improve sleep. 相似文献