Coherent and incoherent J/ΨJ/\Psi photoproduction in PbPbPbPb collisions at the LHC, HE -- LHC and FCC

The coherent and incoherent $J/\Psi$ photoproduction in $PbPb$ collisions are investigated considering the possible states of nucleon configurations in the nuclear wave function and taking into account of the non - linear corrections to the QCD dynamics. The cross sections and the rapidity and transverse momentum distributions are estimated for the energies of the next run of the LHC, High -- Energy LHC and Future Circular Collider. Our results indicate that a future experimental analysis of these processes will be useful to discriminate between different approaches for the QCD dynamics as well to improve our description of the gluon saturation effects.Comment: 7 pages, 3 figures, 1 tabl

Ekstraksi Selulosa dari Serbuk Gergaji Kayu Sengon melalui Proses Delignifikasi Alkali Ultrasonik

Kayu sengon (Albizia chinensis) merupakan salah satu jenis kayu yangmelimpah di Indonesia. Kandungan selulosa pada kayu sengon cukup tinggi sebesar 41,17%. Proses ekstraksi selulosa dari kayu sengon dapat dilakukan melalui proses delignifikasi atau penghilangan kandungan lignin. Umumnya, proses delignifikasi dilakukan dengan larutan alkali pada konsentrasi tinggi, suhu tinggi dan waktu yang lama.Agar konsentrasi alkali yang digunakan rendah dan waktu lebih pendek, proses delignifikasi dapat dilakukan dengan bantuan ultrasonik. Tujuan dari penelitian ini adalah mengetahui pengaruh kondisi operasi (suhu dan waktu) proses delignifikasi dengan ultrasonik terhadap kadar selulosa yang diperoleh. Proses delignifikasi dilakukan denganmencampur serbuk kayu sengon (40 mesh) dengan larutan NaOH (0,3M) dengan perbandingan 1:30 (w/v). Kondisi operasi yang digunakan adalah suhu 30 °C dan 40 °C pada berbagai waktu (10menit hingga 70menit). Setelah proses delignifikasi, produk di bleaching dengan NaOCl hingga warnanya menjadi putih. Analisis yang dilakukan antara lain adalah metode Chesson, X-Ray Diffraction (XRD) dan Scanning Electron Microscopy (SEM). Hasil dari analisa menunjukkan bahwa kristalinitas tertinggi diperoleh sebesar 77,05 % pada 40 °C selama 30 menit dan kadar lignin turun hingga mencapai 0,41%

Determinação de minerais em grãos de milho: avaliação de contaminações durante o preparo de amostras.

O melhoramento de culturas com altos teores de minerais, principalmente Fe e Zn, é uma nova iniciativa no combate à desnutrição, como proposto pelo Programa Harvest Plus. A obtenção de dados analíticos confiáveis sobre carotenóides, pró-vitamínicos A e microminerais nos alimentos escolhidos pelo programa, in natura, processados ou preparados para o consumo, do campo à mesa, é imprescindível para cumprir seus objetivos. Assim, para aumento de confiabilidade, esse programa necessita gerar conhecimento básico sobre as análises de tais características, desenvolvendo protocolos de amostragem e análise para as diversas culturas envolvidas, procurando-se evitar erros relacionados à amostragem ou possíveis contaminações durante as fases de coleta e preparo das amostras. Os protocolos devem atender características relacionadas a custos, exatidão e precisão, além de promover respostas rápidas para facilitar a identificação de genótipos promissores e para treinamento do corpo técnico envolvido aumentando o poder das pesquisas em elementos-traço nas diversas culturas (Stangoulis, 2005). Os analistas devem ser muitos bem informados sobre a natureza e propriedades dos elementos determinados, assim como das fontes de erros na sua identificação e quantificação (Amaya, 2005).SCHAFFERT, R. E

Biovalorization of technical lignins for added-value products and applications

Lignin is an abundant non-toxic amorphous natural polymer. Nowadays it is available a great variety and large amounts of technical lignins as by-products from the pulp and paper industries. Some successful biotechnological applications of enzymatically modified lignins are described in the literature, namely for the production of lignin based copolymers, binders for wood composites, chelating agents, compositions for treating porous materials, coatings, paintings and others. From a new species from Bjerkandera genus which exhibits high decolourisation activity on Poly R-478 and Remazol Brilliant Blue R (RBBR) dyes, was isolated, purified and identified the main enzyme responsible for Remazol Brilliant Blue R dye decolourisation. Such an enzyme is able to oxidise manganese, as well as VA and DMP in manganese-independent reactions; the enzyme substrate range for oxidation of several phenolic and non-phenolic aromatic compounds was determined. This enzyme was tested for transformation of a lignin fraction obtained from straw pulping. Characterisation by gel filtration chromatography of the evolution of the molecular mass distribution of the lignin fragments generated by said enzyme indicated that this enzyme is able to interact directly with lignin in the absence of other mediators