304 research outputs found

    Uji Efektifitas Daya Bersih Beberapa Sediaan Surfaktan terhadap Residu Pestisida pada Buah Apel Segar: Cleaning effectivity of several surfactans to pestisides residues on fresh apel fruits

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    Usaha intensifikasi di bidang pertanian untuk meninglcatkan produktivitas hash tanam tidak dapat terlepas dari penggunaan pestisida, terutama insektisida dan herbisida. Beberapa pestisida yang masih digunakan diantaranya adalah golongan karbofuran dan beberapa golongan organoklorin. Beberapa pestisida bersifat lipofil dan dapat mengganggu kesehatan manusia. Oleh karena itu diperlukan usaha untuk menghilangican pestisida yang terdapat dalam hash tanam. Pencucian adalah salah satu usaha yang dapat dilakukan. Mengingat sifatnya yang lipofil, maka pencucian menggunakan air saja tidaklah cukup. Diperlukan surfaktan untuk meningkatkan daya bersih air. Dalam penelitian ini dilakukan pengamatan daya bersih beberapa surfaktan yang telah beredar di pasaran masing-masing dengan kode SL, ML dan A. Hasil penelitian menunjukkan bahwa sediaan surfaktan yang diteliti memiliki daya bersih terhadap pestisida dalarn buah apel segar dengan harga efektivitas daya bersih surfaktan SL, A, dan ML terhadap DDT berturut-turut 79,18 %, 75,19 % dan 67,49 %, sedangkan terhadap 6-metrin berturut-turut 85,29 % , 80,48 % dan 64,47 %. Kato kunci pestisida, daya bersih surfaktan, DDT, 6-metrin ABSTRACT Intensification efforts in farming to increase productivity must consider the pesticide utilization, especially insecticide and herbicide. Several pestisides which are still used include carbofuran and organochlorine, some of them have lipofilic properties and might harm to human health. Therefore, an effort is required to washing off pesticides from farming products is one of the effort which can be performed. Since pesticides has lipofilic properties, therefore cleaning pesticides with water is not sufficient. Surfactant is required to increase washing off ability of water. Wash off ability of several surfactants circulated on the market i. e. SL, ML and A were investigated. The result showed that the wash off ability values of surfactants to DDT residues on fresh apples were 79.18 %, 75.19 % and 67.49 % for SL, A and ML respectively. The wash off effectiveness of surfactant A, SL and ML to 6-metrine were 85.29 %, 80.48 % and 64.47 % respectively. Key words: pesticide, cleaning efficiency surfactant, DDT, 8-metrin

    The strangeness form factors of the proton

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    The present empirical information on the strangeness form factors indicates that the corresponding uudssˉuuds\bar s component in the proton is such that the uudsuuds subsystem has the flavor spin symmetry [4]FS[22]F[22]S[4]_{FS}[22]_F[22]_S and mixed orbital symmetry [31]X[31]_X. This uudssˉuuds\bar s configuration leads to the empirical signs of all the form factors GEsG_E^s, GMsG_M^s and GAsG_A^s. An analysis with simple quark model wave functions for the preferred configuration shows that the qualitative features of the empirical strangeness form factors may be described with a \sim 15% admixture of uudssˉuuds\bar s with a compact wave function in the proton. Transition matrix elements between the uuduud and the uudssˉuuds\bar s components give significant contributions

    Strangeness in the proton and N*(1535)

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    The newest progress on the study of the strangeness in the proton and in the lowest negative parity nucleon excited state N(1535)N^*(1535) is reviewed. Implications on the internal quark structure of the proton, N(1535)N^*(1535) and other baryons are discussed. The diquark cluster picture for the 5-quark components in baryons gives a natural explanation not only to the empirical indications for a positive strangeness magnetic moment μs\mu_s and positive strangeness radius of the proton but also the longstanding mass-reverse problem of N(1535)N^*(1535), N(1440)N^*(1440) and Λ(1405)\Lambda^*(1405) resonances as well as the unusual decay pattern of the N(1535)N^*(1535) resonance. Evidence for possible existence of N(1535)N^*(1535)'s 1/2{1/2}^- SU(3) nonet partners in this picture is pointed out, and suggestion is made to search for these 1/21/2^- hyperon excited states under the well known Σ(1385)\Sigma^*(1385), Λ(1520)\Lambda^*(1520) and Ξ(1530)\Xi^*(1530) peaks in various reactions.Comment: 6 pages, 2 figures, Plenary talk at 18th International IUPAP Conference on Few-Body Problems in Physics August 21-26. 2006 Santos SP Brazil; to be published in Nuclear Physics

    People Tracking in Camera Networks: Three Open Questions

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    Proton strangeness form factors in (4,1) clustering configurations

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    We reexamine a recent result within a nonrelativistic constituent quark model (NRCQM) which maintains that the uuds\bar s component in the proton has its uuds subsystem in P state, with its \bar s in S state (configuration I). When the result are corrected, contrary to the previous result, we find that all the empirical signs of the form factors data can be described by the lowest-lying uuds\bar s configuration with \bar s in P state that has its uuds subsystem in SS state (configuration II). Further, it is also found that the removal of the center-of-mass (CM) motion of the clusters will enhance the contributions of the transition current considerably. We also show that a reasonable description of the existing form factors data can be obtained with a very small probability P_{s\bar s}=0.025% for the uuds\bar s component. We further see that the agreement of our prediction with the data for G_A^s at low-q^2 region can be markedly improved by a small admixture of configuration I. It is also found that by not removing CM motion, P_{s\bar s} would be overestimated by about a factor of four in the case when transition dominates over direct currents. Then, we also study the consequence of a recent estimate reached from analyzing the existing data on quark distributions that P_{s\bar s} lies between 2.4-2.9% which would lead to a large size for the five-quark (5q) system, as well as a small bump in both G^s_E+\eta G^s_M and G^s_E in the region of q^2 =< 0.1 GeV^2.Comment: Prepared for The Fifth Asia-Pacific Conference on Few-Body Problems in Physics 2011 in Seoul, South Korea, 22-26 August 201

    Penta-quark states with hidden charm and beauty

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    More and more hadron states are found to be difficult to be accommodated by the quenched quark models which describe baryons as 3-quark states and mesons as antiquark-quark states. Dragging out an antiquark-quark pair from the gluon field in hadrons should be an important excitation mechanism for hadron spectroscopy. Our recent progress on the penta-quark states with hidden charm and beauty is reviewed.Comment: Plenary talk at the 5th Asia-Pacific Conference on Few-Body Problems in Physics 2011 (APFB2011), 22-26 Aug., 2011, Seoul, Kore

    Study of qqqccˉqqqc\bar{c} five quark system with three kinds of quark-quark hyperfine interaction

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    The low-lying energy spectra of five quark systems uudccˉuudc\bar{c} (I=1/2, S=0) and udsccˉudsc\bar{c} (I=0, S=-1) are investigated with three kinds of schematic interactions: the chromomagnetic interaction, the flavor-spin dependent interaction and the instanton-induced interaction. In all the three models, the lowest five quark state (uudccˉuudc\bar{c} or udsccˉudsc\bar{c}) has an orbital angular momentum L=0 and the spin-parity JP=1/2J^{P}=1/2^{-}; the mass of the lowest udsccˉudsc\bar{c} state is heavier than the lowest uudccˉuudc\bar{c} state

    The FLASH pilot survey: An H i absorption search against MRC 1-Jy radio sources

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    We report an ASKAP search for associated H i 21-cm absorption against bright radio sources from the Molonglo Reference Catalogue (MRC) 1-Jy sample. The search uses pilot survey data from the ASKAP First Large Absorption Survey in H i (FLASH) covering the redshift range 0.42 < z < 1.00. From a sample of 62 MRC 1-Jy radio galaxies and quasars, we report three new detections of associated H i 21-cm absorption, yielding an overall detection fraction of. The detected systems comprise two radio galaxies (MRC 2216-281 at z = 0.657 and MRC 0531-237 at z = 0.851) and one quasar (MRC 2156-245 at z = 0.862). The MRC 0531-237 absorption system is the strongest found to date, with a velocity integrated optical depth of. All three objects with detected H i 21-cm absorption are peaked-spectrum or compact steep-spectrum (CSS) radio sources. Two of them show strong interplanetary scintillation at 162 MHz, implying that the radio continuum source is smaller than 1 arcsec in size even at low frequencies. Among the class of peaked-spectrum and compact steep-spectrum radio sources, the H i detection fraction is. All three detections have a high 1.4 GHz radio luminosity, with MRC 0531-237 and MRC 2216-281 having the highest values in the sample,. The preponderance of extended radio sources in our sample could partially explain the overall low detection fraction, while the effects of a redshift evolution in gas properties and AGN UV luminosity on the neutral gas absorption still need to be investigated

    Pulsar-wind nebulae and magnetar outflows: observations at radio, X-ray, and gamma-ray wavelengths

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    We review observations of several classes of neutron-star-powered outflows: pulsar-wind nebulae (PWNe) inside shell supernova remnants (SNRs), PWNe interacting directly with interstellar medium (ISM), and magnetar-powered outflows. We describe radio, X-ray, and gamma-ray observations of PWNe, focusing first on integrated spectral-energy distributions (SEDs) and global spectral properties. High-resolution X-ray imaging of PWNe shows a bewildering array of morphologies, with jets, trails, and other structures. Several of the 23 so far identified magnetars show evidence for continuous or sporadic emission of material, sometimes associated with giant flares, and a few possible "magnetar-wind nebulae" have been recently identified.Comment: 61 pages, 44 figures (reduced in quality for size reasons). Published in Space Science Reviews, "Jets and Winds in Pulsar Wind Nebulae, Gamma-ray Bursts and Blazars: Physics of Extreme Energy Release

    Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}} = 2.76 TeV

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    Inclusive transverse momentum spectra of primary charged particles in Pb-Pb collisions at sNN\sqrt{s_{_{\rm NN}}} = 2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0-5% and 70-80% of the hadronic Pb-Pb cross section. The measured charged particle spectra in η<0.8|\eta|<0.8 and 0.3<pT<200.3 < p_T < 20 GeV/cc are compared to the expectation in pp collisions at the same sNN\sqrt{s_{\rm NN}}, scaled by the number of underlying nucleon-nucleon collisions. The comparison is expressed in terms of the nuclear modification factor RAAR_{\rm AA}. The result indicates only weak medium effects (RAAR_{\rm AA} \approx 0.7) in peripheral collisions. In central collisions, RAAR_{\rm AA} reaches a minimum of about 0.14 at pT=6p_{\rm T}=6-7GeV/cc and increases significantly at larger pTp_{\rm T}. The measured suppression of high-pTp_{\rm T} particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb-Pb collisions at the LHC.Comment: 15 pages, 5 captioned figures, 3 tables, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/98
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