To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Improved plasticity models require simultaneous experimental local strain and microstructural evolution data. Microscopy tools, such as electron backscatter diffraction (EBSD), that can monitor transformation at the relevant length-scale, are often incompatible with digital image correlation (DIC) techniques required to determine local deformation. In this paper, the viability of forescatter detector (FSD) images as the basis for the DIC study is investigated. Standard FSD and an integrated EBSD/FSD approach (Pattern Region of Interest Analysis System: PRIAS™) are analyzed. Simultaneous strain and microstructure maps are obtained for tensile deformation of Q&P 1180 steel up to ~14% strain. Tests on an undeformed sample that is simply shifted indicate a standard deviation of error in strain of around 0.4% without additional complications from a deformed surface. The method resolves strain bands at ~2 μm spacing but does not provide significant sub-grain strain resolution. Similar resolution was obtained for mechanically polished and electropolished samples, despite electropolished surfaces presenting a smoother, simpler topography. While the resolution of the PRIAS approach depends upon the EBSD step size, the 80 nm step size used provides seemingly similar resolution as 8,000× (22.7 nm) FSD images. Surface feature evolution prevents DIC analysis across large strain steps (>6% strain), but restarting DIC, using an FSD reference image from an interim strain step, allows reasonable DIC across the stress–strain curve. Furthermore, the data are obtained easily and provide complementary information for EBSD analysis.
The community composition of zooplankton with an emphasis on copepods was assessed in the frontal zones of the Indian sector of the Southern Ocean (SO) during summer 2013. Copepods were the dominant group in both the bongo net and multiple plankton sampler across the entire region. High zooplankton abundance was recorded along each transect in the Polar Front (PF). Community structure in this front was dominated by common taxa, including Ctenocalanus citer, Clausocalanus spp., Calanoides acutus, Calanus propinquus, Calanus australis and Rhincalanus gigas, which together accounted for > 62% of the total abundance. Calocalanus spp., Neocalanus tonsus and C. propinquus were indicator species in the Sub-Tropical Front (STF), Sub-Antarctic Front and PF, respectively. A strong contrast in population structure and biovolume was observed between then PF and the STF. The community structure of smaller copepods was associated with the high-temperature region, whereas communities of larger copepods were associated with the low-temperature region. Thus, it seems probable that physical and biological characteristics of the SO frontal regions are controlling the abundance and distribution of zooplankton community structure by restricting some species to the warmer stratified zones and some species to the well-mixed zone.
The difference in the defect structures produced by different ion masses in a tungsten lattice is investigated using 80 MeV Au7+ ions and 10 MeV B3+ ions. The details of the defects produced by ions in recrystallized tungsten foil samples are studied using transmission electron microscopy. Dislocations of type b = 1/2 and  were observed in the analysis. While highly energetic gold ion produced small clusters of defects with very few dislocation lines, boron has produced large and sparse clusters with numerous dislocation lines. The difference in the defect structures could be due to the difference in separation between primary knock-on atoms produced by gold and boron ions.
We have used the Coronagraphic and Heliospheric Imaging data from Solar TErrestrial RElations Observatory (STEREO) to observe a prominence which is erupted on June 7th 2011. This prominence is subjected to the morphological evolution of MRT instability from the lower solar corona upto the inter-planetary space. The unstable structures are converted into the bunch of localized plasma spikes due to the turbulent mixing, and propagate in the inter-planetary space upto 1 A.U.
Active sun is characterized by compelling short-lived flash of solar eruption like solar flare, coronal mass ejections (CMEs), high-speed solar winds and solar energetic particles along with colossal release of energy and mass. This paper proposes a new method to evaluate solar wind parameters and geomagnetic indices based on wavelet analysis during the solar flares. The crucial role of IMF-Bz (interplanetary magnetic field) is examined for the two solar flares events. The key result obtained from our study is substantial dependence of solar flare intensity on IMF-Bz together with solar wind velocity. We also observed the duration of solar flares and their effect on ionospheric and ground based parameters.
The Sun is an active star and its magnetic field fluctuates from a fraction of a second to a long period of time. The solar wind, CME, solar prominence, solar flares, solar particle and solar filament are the direct result of solar magnetic activity effects on the interplanetary space, Earth’s magnetosphere and ionosphere. The intensity of irruption of these phenomena from the Sun’s surface depends upon its phases. The extreme events affect technology both in space and on the ground.The data obtained from series of observations can help to predict solar activities and safekeeping to the space technology. In this study the cross correlations between IMF Bz, solar wind velocity(Vsw) and interplanetary electric field(Ey) with AE and SYM-H are studied. The results reveal that strong geomagnetic disturbances have high impact on the components of space weather than weak disturbances have.
The occurrence of pesticidal pollution in the environment and the resistance in the mosquito species makes an urge for the safer and an effective pesticide. Permethrin, a poorly water-soluble pyrethroid pesticide, was formulated into a hydrodispersible nanopowder through rapid solvent evaporation of pesticide-loaded oil in water microemulsion. Stability studies confirmed that the nanopermethrin dispersion was stable in paddy field water for 5 days with the mean particle sizes of 175.3 ± 0.75 nm and zeta potential of −30.6 ± 0.62 mV. The instability rate of the nanopermethrin particles was greater in alkaline (pH 10) medium when compared with the neutral (pH 7) and acidic (pH 4) dispersion medium. The colloidal dispersion at 45°C was found to be less stable compared with the dispersions at 25 and 5°C. The 12- and 24-h lethal indices (LC50) for nanopermethrin were found to be 0.057 and 0.014 mg l−1, respectively. These results were corroborative with the severity of damages observed in the mosquito larvae manifested in epithelial cells and the evacuation of the midgut contents. Further, the results were substantiated by the decrease in cellular biomolecules and biomarker enzyme activity in nanopermethrin treated larvae when compared to bulk and control treatment.
This paper investigates the non-linear coaxial (or coupled mode) propagation of Laguerre–Gaussian (LG) (in particular L01 mode) and Gaussian electromagnetic (em) beams in a homogeneous plasma characterized by ponderomotive and relativistic non-linearities. The formulation is based on numerical solution of non-linear Schrödinger wave equation under Jeffreys–Wentzel–Kramers–Brillouin approximation, followed by paraxial approach applicable in the vicinity of intensity maximum of the beams. A set of coupled differential equations for spot size (beam width) and phase evolution with space corresponding to coupled mode has been derived and numerically solved to determine the propagation dynamics. Using focusing equation a critical condition describing the self-trapped (i.e., spatial soliton) mode of laser beam propagation in the plasma has been discussed; as a consequence oscillatory focusing/defocusing of the beams in coupled mode propagation have been analyzed and presented graphically. As an important outcome, significant enhancement in the intensity of LG beam is noticed when it is coupled with the Gaussian mode.
Long-term tillage and fertilizer experiments were conducted in rice in kharif followed by lentil in dry subhumid Inceptisols at Varanasi and Faizabad; horse gram at Phulbani and linseed at Ranchi in moist subhumid Alfisols in rabi during 2001 to 2010. The study was conducted to assess the effect of conventional tillage (CT), low tillage + interculture (LT1) and low tillage + herbicide (LT2) together with 100% N (organic) (F1), 50% N (organic) + 50% N (inorganic) (F2) and 100% N (inorganic) (F3) on productivity, profitability, rainwater and energy use efficiencies. The results at Varanasi revealed that CT was superior with mean yield of 2389 kg ha−1, while F1 was superior with 2378 kg ha−1 in rice. At Faizabad, CT was superior with mean rice yield of 1851 kg ha−1 and lentil yield of 977 kg ha−1, while F1 was superior with 1704 and 993 kg ha−1 of rice and lentil, respectively. At Phulbani, F2 was superior with rice yield of 1170 kg ha−1. At Ranchi, F2 with rice yield of 986 kg ha−1 and F3 with linseed yield of 224 kg ha−1 were superior. The regression model of crop seasonal rainfall and yield deviations indicated an increasing trend in rice yield over mean (positive deviation) with increase in rainfall at all locations; while a decreasing trend (negative deviation) was found for lentil at Faizabad, horse gram at Phulbani and linseed at Ranchi. Based on economic analysis, CTF1 at Varanasi and Faizabad, CTF2 at Phulbani and LT2F2 at Ranchi were superior.
The dispersion relation for lattice waves in a linear chain of charged particles in a complex plasma has been derived on the basis of a screened inter-grain repulsive potential and an attractive shadow potential 1/r. It is seen that the inclusion of the attractive potential makes a significant difference in the results; the present results are in good agreement with the experiment. The dispersion relations, corresponding to square and hexagonal planar lattices, with vibrations confined to the plane have also been derived.
Optimizing magnetic field sensors made by piezoelectric-magnetostrictive composites is a trade off between several parameters. Whereas large structures will cause in principle high electrical currents the mechanical coupling will lead to shear losses and therefore limit the sensitivity of the sensor and make it impossible to measure small magnetic fields. In very small structures the shear losses will decrease but the imperfections in the interfaces become more important and the typically small currents will be disturbed by, e.g., surface conductivity of the piezoelectric material and are thus difficult to measure. The best compromise is a mesoscale sensor which has relatively small losses due to shearing but still high enough electrical currents to work as a good sensor. We will present a setup which allows the use free standing ZnO micro rods as piezoelectric core material which are surrounded by a magnetostrictive layer. Since no clamping is necessary the expansion and contraction of the material is not hindered by a matrix material. The tuning of the relative layer thicknesses can be easily optimized by changing the thickness of the magnetostrictive layer so that an optimum can be achieved for different ZnO micro rods. For the growth of the ZnO a newly developed process will be presented which allows the growth of a large variety of single crystals with different aspect ratios up to needles with several millimeters in length.
The cultivar Ajaya (IET 8585) exhibits durable broad-spectrum resistance to bacterial blight (BB) disease of rice and is widely used as a resistance donor. The present study was carried out to decipher the genetics of BB resistance in Ajaya and map the gene(s) conferring resistance. Genetic analysis in the F2 indicated a quantitative/additive nature of resistance governed by two loci with equal effects. Linked marker analysis and allelic tests revealed that one of the resistance genes is xa5. Sequence analysis of a 244 bp region of the second exon of the gene-encoding Transcription factor IIAγ (the candidate gene for xa5) confirmed the presence of xa5. Bulked-segregant analysis (BSA) revealed the putative location of the two quantitative trait loci (QTLs)/genes associated with resistance on chromosomes 5 and 8. Composite interval mapping located the first locus on Chr. 5S exactly in the genomic region spanned by xa5 and the second locus (qtl BBR 8.1) on Chr. 8L. Owing to its differential disease reaction with a set of seven hyper-virulent isolates of Xanthomonas oryzae, a map location on Chr. 8L, which was distinct from xa13 and data from allelism tests, the second resistance locus in Ajaya was determined to be novel and was designated as xaAj. A contig map spanning xaAj was constructed in silico and the genomic region was delimited to a 13·5 kb physical interval. In silico analysis of the genomic region spanning xaAj identified four putatively expressed candidate genes, one of which could be involved in imparting BB resistance in Ajaya along with xa5.
Long-term field experiments were conducted at Agra, Solapur and Hisar from 2000 to 2008 to identify efficient tillage and nutrient management practices and to develop predictive models that would describe the relationship between crop yields and monthly rainfall for rainfed pearl millet grown on arid and semi-arid Inceptisol, Vertisol and Aridisol soils. Nine treatments comprising a factorial combination of three tillage practices, viz., conventional tillage (CT), low tillage + interculture (LT1) and low tillage + herbicide (LT2) and three fertilizer treatments viz., 100% N from an organic source (F1), 50% organic N + 50% inorganic N (F2) and 100% inorganic N (F3) were tested in a split-plot design at the three locations. Studies revealed that tillage and fertilizer treatments, and their interactions, significantly influenced pearl millet grain yields at the three locations. Prediction models describing the relation between grain yield and monthly rainfall indicated that rainfall occurring in June, July and August at Agra; June and July at Solapur; and June and August at Hisar significantly influenced pearl millet grain yield attained by different treatments. The R2 values of the model ranged from 0.64 to 0.81 at Agra; 0.63 to 0.92 at Solapur, and 0.75 to 0.89 at Hisar. When averaged over all the treatment combinations, mean pearl millet grain yields varied from 1590 to 1744 kg ha−1 at Agra; 1424 to 1786 kg ha−1 at Solapur; and 1675 to 1766 kg ha−1 at Hisar while their corresponding sustainability yield indice (SYI) varied from 35.4 to 42.2%, 19.9 to 45.6% and 64.1 to 68.3%, respectively. At Agra (Inceptisol), CTF3 resulted in significantly higher mean net returns (Rs 11 439 ha−1), benefit-cost ratio (2.33), rainwater use efficiency (RWUE) (3.52 kg ha−1 mm−1) and the second best SYI (39.9%). At Solapur (Vertisol), the LT1F3 resulted in significantly higher net returns (Rs 12 818 ha−1), benefit-cost ratio (3.52), RWUE (3.89 kg ha−1 mm−1) and the fourth best SYI (42.6%). At Hisar (Aridisol), the LT1F3 treatment gave higher net returns (Rs 3866 ha−1), benefit-cost ratio (1.26), RWUE (5.05 kg ha−1 mm−1) and the fourth best SYI (67.8%). These treatment combinations can be recommended for their respective locations to achieve maximum RWUE, productivity and profitability.
We present a numerical study of the reversals and reorientations of the large-scale circulation (LSC) of convective fluid in a cylindrical container of aspect ratio one. We take Prandtl number to be 0.7 and Rayleigh numbers in the range from 6 × 105 to 3 × 107. It is observed that the reversals of the LSC are induced by its reorientation along the azimuthal direction, which are quantified using the phases of the first Fourier mode of the vertical velocity measured near the lateral surface in the midplane. During a ‘complete reversal’, the above phase changes by around 180°, leading to reversals of the vertical velocity at all the probes. On the contrary, the vertical velocity reverses only at some of the probes during a ‘partial reversal’ with phase change other than 180°. Numerically, we observe rotation-led and cessation-led reorientations, in agreement with earlier experimental results. The ratio of the amplitude of the second Fourier mode and the first Fourier mode rises sharply during the cessation-led reorientations. This observation is consistent with the quadrupolar dominant temperature profile observed during the cessations. We also observe reorientations involving double cessation.
The Internet is becoming an increasingly important management tool in production agriculture. Using data from the 2004 Agricultural Resource Management Survey (ARMS) and a double-hurdle estimation approach, we explore the adoption of computers with Internet access by and Internet purchasing patterns of farm households. Adoption of the Internet is positively related to age and education of the operator, off-farm work, presence of spouse, participation in government programs, farm size, and regional location of the farm. Internet purchasing patterns of farm households are positively related to the education of the operator and spouse, presence of teenagers, and regional location of the farm. Finally, farm businesses and their households are more likely to purchase a greater percentage of non-durable goods through the Internet as distances to markets increase.
Analyses of sulphur isotope compositions in sedimentary pyrites from the Vindhyan, Chattisgarh and Cuddapah basins show heavy δ34S (> +25 ‰) values during the Mesoproterozoic. The data provide evidence in support of a hypothesized global Proterozoic sulphidic anoxic ocean where very low concentrations of marine sulphate, bacterially reduced in closed systems, produced δ34S values in pyrites similar to or even heavier than marine sulphate. The extreme environmental conditions induced by these anoxic oceans could have been responsible for the delayed oxygenation of the biosphere and retarded evolution of multicellular life.
Osteopontin, a glycoprotein, is expressed in several tissues including the mammary gland. The gene has been reported to be associated with milk and its constituents in various livestock species. This gene was sequenced in buffalo and it coded for the protein of 280 amino acids with the conserved GRGDS domain. The sequence was confirmed from the cDNA sequence derived from the mammary gland of buffalo. The earlier-reported 9T/10T variation in the upstream region of the gene was investigated for its effect on milk in buffalo and it was found to be non-significant.
We studied the effect of extended defects on electrical characteristics of Si doped n-type nonpolar a-plane GaN films. The n-type GaN layers were grown on co-loaded reduced defect density sidewall lateral epitaxial overgrowth (SLEO) a-plane GaN templates and high defect density planar a-plane GaN templates by metalorganic chemical vapor deposition (MOCVD). The highest conductivity value was observed at the carrier concentration of 1.05 × 1019 cm−3 as 261.12 cm2/Vs for SLEO a-GaN and 106.77 cm2/Vs for the planar a-plane GaN samples. At the same doping level, the carrier compensation for SLEO samples was ∼12% less than planar samples.
This paper reports structural, morphological, optical and humidity sensing characteristics of pulsed laser deposited ZnO film. The XRD pattern reveals amorphous structure of the film. Scanning electron micrograph indicates formation of ZnO rods in micron size. Transmission increases gradually in the UV-VIS region. For studying the humidity sensing characteristics of the film, base of a right angled isosceles glass prism has been coated. Chopped light from a polarized He-Ne laser incident on the entry face of the prism gets reflected from the base – film – humid air interfaces and then emergent light is collected by the detector placed in front of the exit face of the prism. The least change in relative humidity which could be measured using the present configuration is 1.06RH%. Further the film is annealed at 400°C for four hours and its humidity sensing behavior is investigated in the similar manner which now shows a reversed trend. The sensitivity to humidity has decreased and the least change which could be detected now is 1.16RH%.