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In maize soybean intercropping-system maize plants significantly increase the shade density at soybean canopy, and few people studied the threshold level of shade for sustainable production of soybean in this system. This experiment was started to determine the effect of four different shade treatments T75 (75%); T50 (50%); T25 (25%); T0 (0%, control) on morphology, physiology and yield of soybean plants. Relative to T75, treatments T25 and T0 significantly increased the stem diameter and stem breaking strength while plant height was decreased. The chlorophyll a, chlorophyll b, and chlorophyll a + b, photosynthetic and chlorophyll fluorescence characteristics were improved as shade decreased, and maximum values were observed in T25 and T0. Similarly, enzymatic activity of Rubisco was accelerated from T75 to T0. However, genes related to sucrose synthesis (SS and SPS) were down-regulated by increasing shade (T75). Importantly, non-significant differences were measured for seed-yield between T25 and T0, and the plants of soybean under T25 produced 88% of T0 yield. Overall, these results implied that agronomist should develop an appropriate intercropping planting pattern where the maximum shade density ranges from 20 to 30 % to obtain higher seed yield of soybean crop under intercropping-system. [ABSTRACT FROM AUTHOR]

Scattering of electromagnetic waves from a perfectly electrical conducting (PEC) cylinder of circular cross-section, coated with uniaxial non-magnetic chiral anisotropic medium, was discussed. A conducting sheath helix structure with adjustable pitch angle exists over the outer surface of coated cylinder, which is interfaced with the free-space. Under the uniform parallel polarized plane wave with fixed oblique incidence angle, the echo widths were determined emphasizing the other relevant scattering-related parameters (e.g. scattering/extinction efficiency etc.), taking into account different pitch angle values (of the sheath helix) and the kinds of coating mediums. The results revealed that the coating of negative uniaxial chiral medium causes enhancement in scattering efficiency (of the scatterer). Also, the scattering efficiency was found to be the same as the extinction efficiency, thereby yielding vanishing absorption of the medium. The obtained results were also compared with the situation of vanishing chirality of coating medium over the PEC cylinder; the echo width and scattering efficiency both decrease in this case. [ABSTRACT FROM AUTHOR]

ABSTRACT An experimental study into the consequences of diluting isocyanate toward processing of polyurea has been reported. The effect of introducing increasing amount of propylene carbonate into a representative isocyanate precursor has been established. Viscosity-blending index based equations were found to be more reliable toward prediction of isocyanate precursor-propylene carbonate blend viscosity. Spraying of undiluted isocyanate precursor with amine formulations led to formation of 'noodle-like' fibrous product, irrespective of the type of chain extender being used. Diluting isocyanate with propylene carbonate (10% v/v), lowered the viscosity of the precursor from 85 to 48 mPa s (at 70 °C), and the resulting formulations could be effectively sprayed to form polyurea films with excellent mechanical properties. Dilution with propylene carbonate also increased the 'tack free' time appreciably from ∼1 to ∼4 s, which directly reflects on the improved processability. Rheological studies were performed to quantify the activation energy associated with the isocyanate-amine reaction for polyurea preparation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45869. [ABSTRACT FROM AUTHOR]

Zeolitic Imidazolate Frameworks (ZIF) is one of the potential candidates as highly conducting networks with large surface area with a possibility to be used as catalyst support for low temperature fuel cells. In the present study, highly active state-of-the-art Pt Co@NCNTs (Nitrogen Doped Carbon Nanotube) catalyst was synthesized by pyrolyzing ZIF-67 along with Pt precursor under flowing Ar H 2 atmosphere. The multi-walled NCNTs were densely grown on the surface of ZIF particles after pyrolysis. The high resolution TEM examination was employed to examine the nature of the Pt Co particles as well as multi-walled NCNTs. Rotating disk electrode study was used for measuring oxygen reduction reaction performance for Pt Co@NCNTs in 0.1 M HClO 4 and compared with commercial Pt/C catalyst. Fuel cell performance with Pt Co@NCNT and commercial Pt/C catalysts was evaluated at 70 °C using Nafion-212 electrolyte using H 2 and O 2 gases (100% RH) and the observed peak power density of 630 and 560 mW cm −2 , respectively. [ABSTRACT FROM AUTHOR]

Fungus-growing termites (Macrotermitinae) are important pests in tropical countries. They are difficult to control with existing baiting methods, as chitin synthesis inhibitors are not effectual as active ingredients. We tested two neurotoxins, fipronil and imidacloprid, as potential bait active ingredients against Macrotermes gilvus (Hagen) in Singapore. In laboratory bioassays, M. gilvus showed no preference for doses of 0-64 ppm fipronil, or for doses of 0-250 ppm imidacloprid, indicating no repellence. We tested each insecticide in toilet paper as a bait matrix in a field experiment. After 28 days, termites had eaten 5-13% of the fipronil treated toilet paper, abandoned bait and monitoring stations, contacted no new stations, and repaired poorly their experimentally damaged mounds. Termites ate no imidacloprid treated toilet paper, abandoned bait stations although contacted new stations, and repaired fully their damaged mounds. Termites ate 60-70% of the control toilet paper, remained in bait stations, and fully repaired damaged mounds. After 56 days, all five fipronil colonies were eliminated, whereas all of the imidacloprid and control colonies were healthy. The results suggest that fipronil could be an effective active ingredient in bait systems for fungus-growing termites in tropical countries. [ABSTRACT FROM AUTHOR]

Ti–Ta and Ti–Ta–xSn shape memory alloys (SMAs) were produced successfully by microwave sintering. Tin element was added to Ti–Ta SMA with three different atomic percentages (0.37, 0.745 and 2.26 at.%). The influences of Sn addition on microstructure, transformation temperatures, mechanical properties, shape memory behaviours, corrosion resistance and bioactivity were investigated. It was found that the morphologies of the modified and unmodified Ti–Ta alloys contain a plate-like and needle-like structure, where the former structure is related to the β phase and the latter related to the α phase. The transformation temperatures of Ms to Mf with and without Sn additions were observed to be in the range of 389.65 to 355 K, while the transformation temperatures of As to Af were found to be in the range of 250.42 to 365.8 K. By increasing the proportion of Sn, the compressive fracture strength and shape memory behaviour were enhanced; however, the corrosion resistance tended to be decreased. Based on the bioactivity results, antibacterial activity was improved with the addition of Sn. In conclusion, the existent results indicate that Ti–30 at.% Ta SMAs may be a convenient alternative to Ni–Ti for certain biomedical applications. [ABSTRACT FROM AUTHOR]