In this paper, we study spatiotemporal synchronization activity (STSA) of coupled Gaussian maps in a complex network. Our complex networks are changed stochastically with time. A coupled map lattice (CML) is adopted in Gaussian map as a prototype of a spatiotemporal chaotic systems with variation of parameters. A key motivation is that to determine (i) the effects of variation of randomness, (ii) the effects of variation of coupling strength e , (iii) the effects of variation of parameter α when β is fixed and (iv) the effects of variation of β when parameter α is fixed on the synchronization behaviour. The variation of the basin size with respect to rewiring probability for different coupling strength and basin size with respect to coupling strength e for different randomness, different parameters α and β are also plotted.
Nanoporous structures of a p-type semiconductor, delafossite CuAlO(2), with a high crystallinity have been fabricated through an inorganic/polymer double-gel process and characterized for the first time via Mott-Schottky measurements. The effect of the precursor concentration, calcination temperature, and atmosphere were examined to achieve high crystallinity and photoelectrochemical properties while maximizing the porosity. The optical properties of the nanoporous CuAlO(2) are in good agreement with the literature with an optical band gap of 3.9 eV, and the observed high electrical conductivity and hole concentrations conform to highly crystalline and well-sintered nanoparticles observed in the product. The Mott-Schottky plot from the electrochemical impedance spectroscopy studies indicates a flat-band potential of 0.49 V versus Ag/AgCl. It is concluded that CuAlO(2) exhibits band energies very close to those of NiO but with electrical properties very desirable in the fabrication of photoelectrochemical devices including dye-sensitized solar cells.
In this paper, we passing the value of vertical information sharing in terms of inventory replenishment/requirement from the customer(s)! retailers ! producer ! supplier(s). The constant imprecise fuzzy demands of the goods are made to the retailers by the customers. These goods are produced (along with a defectiveness, which decreases due to learning eects) from the raw materials in the producers production center with a constant production rate(unknown). Producer stores these raw materials in a warehouse by purchasing these from a suppliers and the suppliers collect these raw materials from open market / nature at a constant collection rate (unknown). The whole system is considered for a finite time period with fuzzy demand for finished products and fuzzy inventory costs. Here shortages are allowed and fully backlogged. The fuzzy chance constraints on the available space of the producer and transportation costs for both producer, retailers are defuzzified using necessity approach. Besides, this research tries to looking for a period of inventory management system maintenance so that it can found the minimum cost incurred or which still tolerable for tracking inventory management system itself. Results indicate the eciency of proposed approach in performance measurement. This paper attempts to provide the reader a complete picture of supply chain management through a systematic literature review.
Abortions and stillbirths were noticed in pregnant goats on a farm in the state of Gujarat, India. About 50% of the pregnant goats aborted or gave birth to dead kids. Bluetongue virus (BTV) antibody in the sera of affected goats was detected using a competitive enzyme-linked immunosorbent assay (ELISA). Viral antigen in the blood of these goats and in the aborted fetal spleens was detected using a sandwich ELISA. Two viruses (SKN-9, SKN-10) were isolated in cell culture from aborted fetal spleens and were confirmed as Orbivirus by demonstration of ten bands in RNA polyacrylamide gel electrophoresis and identified as BTV-1 by sequencing of the VP2 gene. Sequence analyses revealed thatthese isolates were very closely related to a BTV-1 (strain SKN-8) isolated from Culicoides vectors captured on the same farm one month after the occurrence of abortion. Isolation of BTV-1 from fetuses is probably evidence of transplacental transmission of the wild-type strain, because attenuated or laboratory-adapted BTV-1 strains have never been used in this region. This may have important implications in the epidemiology of bluetongue, considering the presence of many BTV serotypes in India.
Interaction of CdSe and ZnO nanocrystals with electron-donating tetrathiafulvalene (TTF) and electron-withdrawing tetracyanoethylene (TCNE) has been investigated. Isothermal calorimetry shows CdSe nanocrystals interact more strongly with TCNE than TTF. Interaction of larger CdSe nanocrystals with TCNE causes a red-shift in the band-edge emission because of agglomeration, while the smaller CdSe nanocrystals, exhibiting stronger interaction with TCNE modify the optical gap of the nanocrystal. Luminescence of CdSe gets quenched sharply after addition of both TTF and TCNE. ZnO nanocrystals also exhibit luminescence quenching to lesser extent. Defect-emission of ZnO nanocrystals gets red or blue-shifted after interaction with TTF or TCNE respectively.
Interaction of graphene, graphene oxide, and related nanocarbons with radiation gives rise to many novel properties and phenomena. Irradiation of graphene oxide in solid state or in solution by sunlight, UV radiation, or excimer laser radiation reduces it to graphene with negligible oxygen functionalities on the surface. This transformation can be exploited for nanopatterning and for large scale production of reduced graphene oxide (RGO). Laser-induced dehydrogenation of hydrogenated graphene can also be used for this purpose. All such laser-induced transformations are associated with thermal effects. RGO emits blue light on UV excitation, a feature that can be used to generate white light in combination with a yellow emitter. RGO as well as graphene nanoribbons are excellent detectors of infra-red radiation while RGO is a good UV detector.
The role of defects on laser-excited photoluminescence of various ZnO nanostructures has been investigated. The study shows that defects present in ZnO nanostructures, specially Zn-related defects play a crucial role in determining the laser-excited photoluminescence intensity (LEI). ZnO nanoparticles as well as nanorods (NR) annealed in oxygen atmosphere exhibit remarkable enhancement in LEI. A similar enhancement is also shown by Al-doped ZnO NR.
AbstractInteraction of graphene, graphene oxide, and related nanocarbons with radiation gives rise to many novel properties and phenomena. Irradiation of graphene oxide in solid state or in solution by sunlight, UV radiation, or excimer laser radiation reduces it to graphene with negligible oxygen functionalities on the surface. This transformation can be exploited for nanopatterning and for large scale production of reduced graphene oxide (RGO). Laser‐induced dehydrogenation of hydrogenated graphene can also be used for this purpose. All such laser‐induced transformations are associated with thermal effects. RGO emits blue light on UV excitation, a feature that can be used to generate white light in combination with a yellow emitter. RGO as well as graphene nanoribbons are excellent detectors of infra‐red radiation while RGO is a good UV detector.
A variety of electronic and magnetic states can be obtained for graphene decorated with inorganic nanoparticles, as shown on p. 937 by S. K. Pati, C. N. R. Rao et al.
Gold nanoparticles with average diameters in the range 2.5-15 nm, prepared at the organic/aqueous interface by using tetrakis(hydroxymethyl)phosphonium chloride (THPC) as reducing agent, exhibit ferromagnetism whereby the saturation magnetization M(S) increases with decreasing diameter and varies linearly with the fraction of surface atoms. The value of M(S) is higher when the particles are present as a film instead of as a sol. Capping with strongly interacting ligands such as alkane thiols results in a higher M(S) value, which varies with the strength of the metal-sulfur bond. Ferromagnetism is also found in Pt and Ag nanoparticles prepared as sols, and the M(S) values vary as Pt>Au>Ag. A careful study of the temperature variation of the magnetization of Au nanoparticles, along with certain other observations, suggests that small bare nanoparticles of noble metals could indeed possess ferromagnetism, albeit weak, which is accentuated in the presence of capping agents, specially alkane thiols which form strong metal-sulfur bonds.
Graphenes with varying number of layers can be synthesized by using different strategies. Thus, single-layer graphene is prepared by micromechanical cleavage, reduction of single-layer graphene oxide, chemical vapor deposition and other methods. Few-layer graphenes are synthesized by conversion of nanodiamond, arc discharge of graphite and other methods. In this article, we briefly overview the various synthetic methods and the surface, magnetic and electrical properties of the produced graphenes. Few-layer graphenes exhibit ferromagnetic features along with antiferromagnetic properties, independent of the method of preparation. Aside from the data on electrical conductivity of graphenes and graphene-polymer composites, we also present the field-effect transistor characteristics of graphenes. Only single-layer reduced graphene oxide exhibits ambipolar properties. The interaction of electron donor and acceptor molecules with few-layer graphene samples is examined in detail.
By employing X-ray photoelectron spectroscopy (XPS), we have been able to establish the occurrence of charge-transfer doping in few-layer graphene covered with electron acceptor (TCNE) and donor (TTF) molecules. We have performed quantitative estimates of the extent of charge transfer in these complexes and elucidated the origin of unusual shifts of their Raman G-bands and explained the differences in the dependence of conductivity on n- and p-doping. The study unravels the cause of the apparent difference between the charge-transfer doping and electrochemical doping.
Graphenes with varying number of layers can be synthesized by using different strategies. Thus, single-layer graphene is prepared by micromechanical cleavage, reduction of single-layer graphene oxide, chemical vapor deposition and other methods. Few-layer graphenes are synthesized by conversion of nanodiamond, arc discharge of graphite and other methods. In this article, we briefly overview the various synthetic methods and the surface, magnetic and electrical properties of the produced graphenes. Few-layer graphenes exhibit ferromagnetic features along with antiferromagnetic properties, independent of the method of preparation. Aside from the data on electrical conductivity of graphenes and graphene-polymer composites, we also present the field-effect transistor characteristics of graphenes. Only single-layer reduced graphene oxide exhibits ambipolar properties. The interaction of electron donor and acceptor molecules with few-layer graphene samples is examined in detail.
Commonly used classification algorithms are not capable of incremental learning. When a new pattern is presented to such a computational model, it can either classify the unknown pattern based on its legacy training or declare the pattern as an outlier if such a provision is built into the associated algorithm. In the case of the pattern being an outlier to the existing training model, it is desirable that the same could be seamlessly included in the training model with appropriate class labels so that a universal computational model may be evolved incrementally. To this end, classifiers having the incremental-learning ability can be of great benefit by automatically including the newly presented patterns in the training data set without affecting class integrity of the previously trained system. In the present treatise, an incremental-learning fuzzy model for classification of black tea using electronic nose measurement is proposed. For application in black tea grade discrimination, an attempt has been made to correlate the multisensor aroma pattern of electronic nose with sensory panel (tea tasters) evaluation. However, this problem is associated with 2-D complexities. On one hand, the aroma of tea depends on the agroclimatic condition of a particular location, the specific season of flush, and the clonal variation for the tea plant. On the other hand, the sensory evaluation is completely human dependent that often suffers from subjectivity and nonrepeatability. In our pursuit of developing a universal computational model capable of objectively assigning tea-taster-like scores to tea samples under test, it has been felt that an incremental approach could be extremely beneficial for electronic-nose-based tea quality estimation. To this end, the proposed incremental-learning fuzzy model promises to be a versatile pattern classification algorithm for black tea grade discrimination using electronic nose. The algorithm has been tested in some tea gardens of northeast India, and encouraging results have been obtained.
Surface-enhanced Raman scattering (SERS) of pyridine adsorbed on ultrathin nanocrystalline Au and Ag films generated at the liquid–liquid interface has been investigated. The shifts and intensification of bands formed with these films comprising metal nanoparticles are comparable to those found with other types of Au and Ag substrates. SERS of rhodamine 6G adsorbed on Ag films has also been studied. The results demonstrate that nanocrystalline metal films prepared by the simple method involving the organic–aqueous interface can be used effectively for SERS investigations.
One of the applications of nanomaterials is as reinforcements in composites, wherein small additions of nanomaterials lead to large enhancements in mechanical properties. There have been extensive studies in the literature on composites where a polymer matrix is reinforced by a single nanomaterial such as carbon nanotubes. In this article, we examine the significant synergistic effects observed when 2 different types of nanocarbons are incorporated in a polymer matrix. Thus, binary combinations of nanodiamond, few-layer graphene, and single-walled nanotubes have been used to reinforce polyvinyl alcohol. The mechanical properties of the resulting composites, evaluated by the nanoindentation technique, show extraordinary synergy, improving the stiffness and hardness by as much as 400% compared to those obtained with single nanocarbon reinforcements. These results suggest a way of designing advanced materials with extraordinary mechanical properties by incorporating small amounts of 2 nanomaterials such as graphene plus nanodiamond or nanodiamond plus carbon nanotube.
The mechanical properties of polyvinyl alcohol (PVA) and poly(methyl methacrylate) (PMMA)-matrix composites reinforced by functionalized few-layer graphene (FG) have been evaluated using the nano-indentation technique. A significant increase in both the elastic modulus and hardness is observed with the addition of 0.6 wt% of graphene. The crystallinity of PVA also increases with the addition of FG. This and the good mechanical interaction between the polymer and the FG, which provides better load transfer between the matrix and the fiber, are suggested to be responsible for the observed improvement in mechanical properties of the polymers.
Effects of interaction of graphene with electron donor and acceptor molecules have been investigated by employing Raman spectroscopy. The G band softens progressively with the increasing concentration of tetrathiafulvalene (TTF) which is an electron donor while the band stiffens with increasing concentration of tetracyanoethylene (TCNE) which is an electron-acceptor molecule. Both TTF and TCNE broaden the G-band. The 2D band position is also affected by interaction with TTF and TCNE. The intensity of the 2D-band decreases markedly with the concentration of either. The ratio of intensities of the 2D and G bands decreases with increase in TTF and TCNE concentrations. The electrical resistivity of graphene varies in opposite directions on interaction with TTF and TCNE. All these effects occur due to molecular charge-transfer, as evidenced by the observation of charge-transfer bands in the electronic absorption spectra.