Recomendações técnicas para o cultivo de abobora (Cucurbita moschata L.) no Amapá.

Introdução; Botanica; Cultivares; Clima e época de plantio; Solo; Adubação; Preparo do solo; Preparo de mudas; Transplante; Crescimento e desenvolvimento; Tratos culturais; Doenças; Rotação de culturas; Colheita; Armazenamento; Mercado; Coeficientes técnicos; Bibliografia consultada.bitstream/item/97835/1/CPAF-AP-1999-Recomendacoes-abobora.pd

Slow down of a globally neutral relativistic e−e+e^-e^+ beam shearing the vacuum

The microphysics of relativistic collisionless sheared flows is investigated in a configuration consisting of a globally neutral, relativistic $e^-e^+$ beam streaming through a hollow plasma/dielectric channel. We show through multidimensional PIC simulations that this scenario excites the Mushroom instability (MI), a transverse shear instability on the electron-scale, when there is no overlap (no contact) between the $e^-e^+$ beam and the walls of the hollow plasma channel. The onset of the MI leads to the conversion of the beam's kinetic energy into magnetic (and electric) field energy, effectively slowing down a globally neutral body in the absence of contact. The collisionless shear physics explored in this configuration may operate in astrophysical environments, particularly in highly relativistic and supersonic settings where macroscopic shear processes are stable

Olericultura tropical no Amapá.

As hortaliças se destacam como fontes de carboidratos, vitaminas e sais minerais, necessários para o crescimento e desenvolvimento humano. No entanto, os horticultores do trópico úmido amazônico, enfrentam enormes dificuldades para produzir hortaliças e atender à crescente demanda, principalmente nos grandes centros hurbanos. Problemas como a baixa fertilidade dos solos da floresta tropical de terra firme, as elevadas temperaturas, altos índices de pluviosidade e umidade relativa do ar, e a incidência de pragas, são fatores que dificultam a produção de hortaliças neste ecossistema. Nesse contexto, a Embrapa Amapá vem recomendar cultivares e processos de cultivo, que apresentem bom desempenho nas condições amapaenses.bitstream/item/97365/1/CPAF-AP-2001-Olericultura-tropical.pd

Coleta e conservação de plantas medicinais de interesse econômico para o Estado do Amapá.

Este trabalho objetiva coletar, multiplicar e manter em coleções as espécies medicinais de interesse econômico para o Estado do Amapá.bitstream/item/97471/1/CPAF-AP-2000-Conservacao-plantas.PD

Amplification and generation of ultra-intense twisted laser pulses via stimulated Raman scattering

Twisted Laguerre-Gaussian lasers, with orbital angular momentum and characterised by doughnut shaped intensity profiles, provide a transformative set of tools and research directions in a growing range of fields and applications, from super-resolution microcopy and ultra-fast optical communications to quantum computing and astrophysics. The impact of twisted light is widening as recent numerical calculations provided solutions to long-standing challenges in plasma-based acceleration by allowing for high gradient positron acceleration. The production of ultrahigh intensity twisted laser pulses could then also have a broad influence on relativistic laser-matter interactions. Here we show theoretically and with ab-initio three-dimensional particle-in-cell simulations, that stimulated Raman backscattering can generate and amplify twisted lasers to Petawatt intensities in plasmas. This work may open new research directions in non-linear optics and high energy density science, compact plasma based accelerators and light sources.Comment: 18 pages, 4 figures, 1 tabl

Adubação verde e plantio direto: alternativas de manejo agroecológico para a produção agrícola familiar sustentável.

bitstream/item/62424/1/DOCUMENTOS-212-Embrapa-A-Oriental.pd

Exact solution for the energy density inside a one-dimensional non-static cavity with an arbitrary initial field state

We study the exact solution for the energy density of a real massless scalar field in a two-dimensional spacetime, inside a non-static cavity with an arbitrary initial field state, taking into account the Neumann and Dirichlet boundary conditions. This work generalizes the exact solution proposed by Cole and Schieve in the context of the Dirichlet boundary condition and vacuum as the initial state. We investigate diagonal states, examining the vacuum and thermal field as particular cases. We also study non-diagonal initial field states, taking as examples the coherent and Schrodinger cat states.Comment: 10 pages, 8 figure