Neutron-rich nuclei produced at zero degrees in damped collisions induced by a beam of 18O on a 238U target

Cross sections and corresponding momentum distributions have been measured for the first time at zero degrees for the exotic nuclei obtained from a beam of 18O at 8.5 MeV/A impinging on a 1 mg/cm2 238U target. Sizable cross sections were found for the production of exotic species arising from the neutron transfer and proton removal from the projectile. Comparisons of experimental results with calculations based on deep-inelastic reaction models, taking into account the particle evaporation process, indicate that zero degree is a scattering angle at which the differential reaction cross section for production of exotic nuclei is at its maximum. This result is important in view of the new generation of zero degrees spectrometers under construction, such as the S3 separator at GANIL, for example

Corn yield response to weed and fall armyworm controls

The interference imposed the by weeds on corn decreases practically all vegetative characteristics. As consequence, the green ear and grain yield are also reduced. Losses due to the fall armyworm (Spodoptera frugiperda) attack can reduce corn grain yield up to 34%. In general, weed and insect control issues are addressed separately in research papers. Nevertheless, interaction between weeds and insects may exist. This study aimed to evaluate green ear and corn grain yield response to weed and fall armyworm control. A completely randomized block design with split-plots and five replicates was adopted. Corn cultivar AG 1051 was grown under weedy conditions or with control by hand hoeings performed at 20 and 40 days after planting. Fall armyworm control (applied to subplots) was performed with sprays of water (control), deltamethrin (5g active ingredient ha-1); neem oil, at 0.5% (diluted in water), and neem leaf extract at 5%. Each product was sprayed three times, at seven-day intervals, starting at the 7th day after planting, using 150 L ha-1 of the tank solution. Dry mass of the above-ground part, internode diameter, leaf length, leaf width, leaf area, green ear yield and grain yield of corn were reduced due to the lack of weed control. Fall armyworm control in the weeded plots did not influence green ear yield and grain yield, except green mass of marketable, husked ears, which was reduced when the caterpillar was not controlled. Without weed control, neem extracts and deltamethrin sprays provided highest yields of number and total weight of green ears with husks, number and weight of marketable ears with husks and number of marketable ears without husks. The best results for husked ear mass and for grain yield were obtained with neem extract and deltamethrin, respectively

Produtividade e valor nutricional da silagem de híbridos de milho em diferentes alturas de colheita

Cinco híbridos de milho foram avaliados quanto à produtividade de matéria seca, ao valor nutritivo da silagem e à produtividade de leite. Os híbridos avaliados foram AS 32, AG 9090, CD 308, DKB 747 e P 30F87, colhidos em três alturas de corte: 15, 35 e 55 cm. O delineamento experimental foi em blocos casualizados com parcelas subdivididas e três repetições. Para confecção das silagens, utilizaram-se silos experimentais de PVC com 20 cm de diâmetro e 40 cm de altura. A produtividade de leite, por tonelada de silagem (eficiência alimentar) e por hectare, foi estimada pelo modelo Milk2006. A produtividade de forragem ensilável reduziu com o aumento da altura de colheita, com resultados de 14,6; 13,0 e 12,6 t/ha MS para as alturas de colheita de 15 cm, 35 cm e 55 cm, respectivamente. O híbrido de milho e a altura de colheita influenciaram a composição bromatológica das silagens, com exceção do teor de extrato etéreo (EE), que não foi influenciado pela altura de colheita. Ocorreu interação híbrido × altura de colheita para o teor de amido, a digestibilidade in vitro da MS e da fibra em detergente neutro (FDN) e o teor de nutrientes digestíveis totais (NDT). Houve efeito da altura de colheita sobre a eficiência alimentar, cujos valores médios foram de 1.226, 1.291 e 1.393 kg leite/t silagem nas alturas de colheita de 15, 35 e 55 cm, respectivamente. Observou-se também efeito do tipo de híbrido sobre a produtividade de leite e a eficiência alimentar, com melhores valores verificados para o híbrido DKB 747 colhido na altura de 55 cm. Ao elevar a altura de colheita, melhora-se o valor nutritivo da silagem sem prejudicar a produtividade de leite por hectare. O manejo da altura de corte não substitui a escolha de melhores híbridos para produção de silagem de alta qualidade e produtividade

Silicon Carbide Surface Modification By Nitrogen Plasma Expander

Silicon carbide (SiC) has been employed in many different fields such as ballistic armor, thermal coating, high performance mirror substrate, semiconductors devices, among other things. Plasma application over the silicon carbide ceramics is relatively recent and it is able to promote relevant superficial modifications. Plasma expander was used in this work which was supplied by nitrogen and switched by a capacitor bank. Nitrogen plasma was applied over ceramic samples for 20 minutes, in a total medium of 1440 plasma pulses. SiC ceramics were produced by uniaxial pressing method (40 MPa) associated to isostatic pressing (300 MPa) and sintered at 1950°C under argon gas atmosphere. Silicon carbide (β-SiC - BF-12) supplied by HC-Starck and sintering additive (7.6% YAG - Yttrium Aluminum Garnet) were used in order to obtain the ceramics. Before and after the plasma application, the samples were characterized by SEM, AFM, contact angle and surface energy measurement. © (2012) Trans Tech Publications, Switzerland.727-72814281432 Abbott,Air Products,Ametek,Basf,Brats,Et al.Ercenk, E., Sen, U., Yilmaz, S., (2011) Ceramics International, 37, p. 883Molian, P., Baerga, V.R., (2011) Advances in Applied Ceramics, 110, p. 120Liu, X., Zhoo, X., Fu, R.K.Y., Ho, J.P.Y., Ding, C., Chu, P.K., (2005) Biomaterials, 26, p. 6143Chaim, R., (2007) Materials Science and Engineering A, 443, p. 25Shen, Z., Johnsson, M., Zhoo, Z., Nygren, M., (2002) Journal of the American Ceramic Society, 85, p. 1921Xiem, N.T., Kroisová, D., Louda, P., Hung, T.D., Rozek, Z., (2009) Journal of Achievements in Materials and Manufacturing Engineering, 37, p. 526Fu, R.K.Y., Fu, K.L., (2004) Journal of Vacuum Science and Technology A, 22, p. 356Ceschini, L., Lanzoni, E., Martini, C., Prandstraller, D., Sambogna, G., (2008) Wear, 264, p. 86Bittencourt, J.A., (1986) Fundamentals of Plasma Physics, , Edited by Pergamon Press, OxfordYasuda, H., (1985) Plasma Polymerization, , Edited by Academic Press, Inc., New YorkManos, D.M., Flamm, D.L., (1989) Plasma etching: An introduction, , Edited by Academic Press, San Diego, C. AZeldovich, Y.B., Raizer, Y.P., (2002) Physics of shock waves and high temperature hydrodinamic Phenomena, , Edited by Dover Publications, Inc., New YorkMamum, A.A., Shukla, P.K., (2011) EPL Journal, 94, p. 65002. , doi: 10.1209/0295-5075/94/65002Rocha, R.M., Melo, F.C.L., (2008) Materials Science Forum, 593, p. 493Marins, E.M., (2008) Optimization and microstructural analysis of silicon carbide ceramics obtained of the national materials to ballistic armor application, , Doctorate (Thesis). Guaratinguetá, Universidade Estadual Paulista (UNESP). (SP). (In Portuguese)Navaneetha Pandiyaraj, K., Selvarajan, V., Deshmukh, R.R., Bousmina, M., (2008) Surface and Coatings Technology, 202, p. 422