Статті в журналах: "3P0 model"

1

DA SILVA, D. T., J. N. QUADROS, M. L. L. DA SILVA, and D. HADJIMICHEF. "LIGHT QUARKONIA DECAYS IN THE CORRECTED 3P0 MODEL." International Journal of Modern Physics E 16, no. 09 (October 2007): 2919–22. http://dx.doi.org/10.1142/s0218301307008720.

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The 3P0 model is a typical decay model which considers only OZI-allowed strong decays and considers a quark-antiquark pair creation in the presence of the initial state meson. The quark-antiquark pair is created with the vacuum quantum numbers. This model can also be obtained from the non-relativistic limit of the pair creation Hamiltonian. Applying the Reduced Hilbert Space formalism to the pair creation Hamiltonian will produce the characteristic expansion in powers of the wave function, where the 3P0 model is the lowest order term of this expansion. This new model will correct 3P0, which we call the Corrected 3P0 model or C 3P0 model. The model will be applied to the light quarkonia decay sector.

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2

DA SILVA, D. T., J. N. DE QUADROS, M. L. L. DA SILVA, C. A. Z. VASCONCELLOS, and D. HADJIMICHEF. "C3P0 MODEL FOR CHARMED MESONS DECAY." International Journal of Modern Physics D 19, no. 08n10 (August 2010): 1629–33. http://dx.doi.org/10.1142/s0218271810017457.

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The successful mapping technique, Fock–Tani formalism, has produced a corrected 3P0 model ( C 3P0 model), which retains the basic aspects of the 3P0 predictions with the inclusion of bound-state corrections. The model is applied for charmed mesons decay. The amplitude and its respective decay rates are evaluated.

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3

DE QUADROS, J. N., M. L. L. DA SILVA, D. T. DA SILVA, and D. HADJIMICHEF. "STRANGE MESON DECAY IN THE C3P0 MODEL." International Journal of Modern Physics D 19, no. 08n10 (August 2010): 1647–50. http://dx.doi.org/10.1142/s0218271810017627.

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The successful mapping technique (Fock–Tani formalism) has produced a corrected 3P0 model ( C 3P0 model), which retains the basic aspects of the 3P0 predictions with the inclusion of bound-state corrections. In this work we have evaluated the decay amplitude of a strange quarkonia candidate, namely ϕ(1020). A comparison is made with the non-corrected model.

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4

Cortzen, Isabella, Georgios E. Magdis, Francesco Valentino, Emanuele Daddi, Daizhong Liu, Dimitra Rigopoulou, Mark Sargent, et al. "Deceptively cold dust in the massive starburst galaxy GN20 at z ∼ 4." Astronomy & Astrophysics 634 (February 2020): L14. http://dx.doi.org/10.1051/0004-6361/201937217.

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We present new observations, carried out with IRAM NOEMA, of the atomic neutral carbon transitions [C I](3P1–3P0) at 492 GHz and [C I](3P2–3P1) at 809 GHz of GN20, a well-studied star-bursting galaxy at z = 4.05. The high luminosity line ratio [C I](3P2–3P1) /[C I](3P1–3P0) implies an excitation temperature of 48+14−9 K, which is significantly higher than the apparent dust temperature of Td = 33 ± 2 K (β = 1.9) derived under the common assumption of an optically thin far-infrared dust emission, but fully consistent with Td = 52 ± 5 K of a general opacity model where the optical depth (τ) reaches unity at a wavelength of λ0 = 170 ± 23 μm. Moreover, the general opacity solution returns a factor of ∼2× lower dust mass and, hence, a lower molecular gas mass for a fixed gas-to-dust ratio, than with the optically thin dust model. The derived properties of GN20 thus provide an appealing solution to the puzzling discovery of starbursts appearing colder than main-sequence galaxies above z > 2.5, in addition to a lower dust-to-stellar mass ratio that approaches the physical value predicted for starburst galaxies.

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5

MaruymaA, M., S. Furui, Amand Faessler, and R. Vinh Mau. "annihilation into three mesons in the 3P0 model." Nuclear Physics A 473, no. 4 (November 1987): 649–66. http://dx.doi.org/10.1016/0375-9474(87)90272-7.

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6

Rodrigues, Hercules B., Daniel T. da Silva, and Dimiter Hadjimichef. "The Ds1(2536)+ Decay Widths in the C3P0 Model." International Journal of Modern Physics: Conference Series 45 (January 2017): 1760070. http://dx.doi.org/10.1142/s2010194517600709.

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The Fock-Tani representation is a field theory formalism appropriated for the simultaneous treatment of composite particles and their constituents. The 3P0 model is a typical decay model which considers only OZI-allowed strong decays. The model considers a quark-antiquark pair created with the vacuum quantum numbers in the presence of the initial state meson. It is described as the non-relativistic limit of the pair creation Hamiltonian. Applying the Fock-Tani transformation to the microscopic Hamiltonian of the pair creation produces the characteristic expansion in powers of the wavefunction, where the 3P0 model is the lowest order in the expansion. The corrected 3P0 model (C3P0) is obtained from higher orders in the expansion, by the introduction of the bound state kernel [Formula: see text], called the bound state correction. The goal of this work is to study the application of the 3P0 model and C3P0 model in detail for the strange charmed meson sector ([Formula: see text] meson). In particular, we shall calculate the decay amplitudes and decay rates of the [Formula: see text].

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7

Alanakyan, R. A. "3P0, bottomium decays in the minimal supersymmetric standard model." Physics Letters B 321, no. 4 (February 1994): 378–80. http://dx.doi.org/10.1016/0370-2693(94)90261-5.

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8

DE QUADROS, J. N., та D. HADJIMICHEF. "J/ψ DECAY IN THE C3P0 MODEL". International Journal of Modern Physics: Conference Series 18 (січень 2012): 200–203. http://dx.doi.org/10.1142/s2010194512008458.

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The Fock-Tani representation, is a field theoretic formalism to treat problems involving both composite particles and their constituents. The application of the Fock-Tani transformation to a pair creation Hamiltonian produces the characteristic expansion in powers of the wave function. In lowest order of this expansion, we obtain the model known in the literature: the 3P0 model. In higher orders, the Corrected 3P0 model (C3P0) is obtained by introducing the bound state kernel. In this work, we use the C3P0 model to calculate the J/ψ decay rates in the following channels: ρ π, ω η, ω η′, K*+ K-, [Formula: see text], ϕ η, ϕ η′. We consider that the J/ψ is a mixture given by [Formula: see text].

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9

FU, HUI-FENG, XIANG-JUN CHEN, GUO-LI WANG та TIAN-HONG WANG. "OZI-ALLOWED TWO BODY ϒ DECAYS IN THE 3P0 MODEL WITH THE RELATIVISTIC WAVE FUNCTIONS". International Journal of Modern Physics A 27, № 06 (10 березня 2012): 1250027. http://dx.doi.org/10.1142/s0217751x12500273.

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We combine the Bethe–Salpeter method with the 3P0 model to describe OZI-allowed two body meson decays. In this combined method, the relativistic wave functions defined in the Salpeter equation show up in the decay amplitude of the 3P0 model automatically. We apply the method to OZI-allowed ϒ( 4S, 5S, 6S ) two body decays. The results are roughly consistent with the experimental data and the predictions of ϒ( 6S ) decays are given.

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10

SUEBKA, P., C. KOBDAJ та Y. YAN. "ππ REACTION IN NON-RELATIVISTIC QUARK MODEL". International Journal of Modern Physics E 14, № 07 (жовтень 2005): 987–94. http://dx.doi.org/10.1142/s0218301305003740.

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The reaction π+π-→π+π- is studied in the non-relativistic quark model with the 3P0 quark–antiquark dynamics. The cross section of the reaction π+π-→π+π- is well reproduced even for rather high energies.

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11

Furui, Sadataka. "N annihilation at rest into πππ and Kπ in the 3P0-model". Nuclear Physics B - Proceedings Supplements 8 (червень 1989): 231–34. http://dx.doi.org/10.1016/0920-5632(89)90230-2.

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12

Thierauf, R., T. Gutsche, Y. Yan, A. Muhm, and Amand Faessler. "Low-energy proton-antiproton scattering in the non-relativistic 3P0 quark model." Nuclear Physics A 588, no. 4 (June 1995): 783–800. http://dx.doi.org/10.1016/0375-9474(95)00079-g.

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13

EAKINS, B., and W. ROBERTS. "HEAVY DIQUARK SYMMETRY CONSTRAINTS FOR STRONG DECAYS." International Journal of Modern Physics A 27, no. 27 (October 29, 2012): 1250153. http://dx.doi.org/10.1142/s0217751x12501539.

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The heavy diquark symmetry (HDS) of doubly heavy baryons (DHBs) provides new insights into the spectroscopy of these hadrons. We derive the consequences of this symmetry for the mass spectra and the decay widths of DHBs. We compare these symmetry constraints to results from a nonrelativistic quark model for the mass spectra and results from the 3P0 model for strong decays. The quark model we implement was not constructed with these symmetries and contains interactions which explicitly break HDS. Nevertheless these symmetries emerge. We argue that the 3P0 model and any other model for strong transitions which employs a spectator assumption explicitly respects HDS. We also explore the possibility of treating the strange quark as a heavy quark and apply these ideas to Ξ, Ξc and Ξb baryons.

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14

DA SILVA, D. T., C. A. Z. VASCONCELLOS, and D. HADJIMICHEF. "DECAY PROCESS OF THE CHARMED MESON $D_{2}^{\ast}\,(2460)$ IN THE C3P0 Model." International Journal of Modern Physics: Conference Series 18 (January 2012): 195–99. http://dx.doi.org/10.1142/s2010194512008446.

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The Fock-Tani formalism is a successful mapping technique that has been used in hadron physics to describe hadron interaction and decay. In this one can obtain the 3P0 model with bound state corrections. In this work we applay this technique for [Formula: see text] decay, where the amplitude and its respective decay rates are evaluated.

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15

Bonnaz, R., and B. Silestre-Brac. "Discussion on the 3P0 model applied to the decay of mesons into two mesons." Progress in Particle and Nuclear Physics 44 (March 2000): 369–70. http://dx.doi.org/10.1016/s0146-6410(00)00086-7.

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16

Bauer, E., T. Gutsche, A. Muhm, R. Thierauf, Y. Yan, Amand Faessler, and R. Vinh Mau. "The rho parameter of low energy proton-antiproton scattering in the 3P0 quark model." Physics Letters B 386, no. 1-4 (October 1996): 50–54. http://dx.doi.org/10.1016/0370-2693(96)00974-4.

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17

Campbell, Mark L., Nick Furio, and Paul J. Dagdigian. "The Reaction of Spin–Orbit State-Selected Ca(PJ03) With CH3I, CH2I2, and SF6." Laser Chemistry 6, no. 6 (January 1, 1986): 391–402. http://dx.doi.org/10.1155/lc.6.391.

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Chemiluminescence cross sections for reaction of the individual spin–orbit states of metastable Ca(PJ03) with CH3I, CH2I2, and SF6 have been determined by the use of optical pumping state selection. This technique was also used to separate the chemiluminescence arising from the two excited metastable Ca 3P0 and 1D states. The spin–orbit dependence of the chemiluminescence pathway was found to be substantial for the CH3I and CH2I2 reactions and similar to that previously observed for halogen diatom and alkyl bromide reagents. By contrast, no spin–orbit effect was observed for Ca(3P0)+SF6. These results are discussed in terms of our previously presented model for the origin of spin–orbit effects in chemical reactions.

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18

GREEN, A. M., and G. Q. LIU. "$N\bar N$ ANNIHILATION INTO TWO MESONS IN A RELATIVE D-STATE." Modern Physics Letters A 04, no. 26 (December 10, 1989): 2499–507. http://dx.doi.org/10.1142/s021773238900280x.

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The branching ratios [Formula: see text] and [Formula: see text] are calculated in a model that treats [Formula: see text] annihilation as a two step process- [Formula: see text] annihilation by the 3P0 vertex followed by meson-meson rescattering. This model, successful for other branching ratios, is now found to grossly underestimate these particular ratios. A possible reason for this is given.

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19

Furui, Sadataka. "p annihilation into mesons in the 3P0 model with a planar quark-diagram topology, and in the flux-tube model." Nuclear Physics A 530, no. 3-4 (August 1991): 717–39. http://dx.doi.org/10.1016/0375-9474(91)90776-3.

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20

Furui, Sadataka. "N̄N annihilation into one meson and meson decay into two or three mesons in the 3P0 model." Nuclear Physics A 486, no. 3-4 (September 1988): 541–80. http://dx.doi.org/10.1016/0375-9474(88)90162-5.

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21

Gutsche, T., M. Maruyama, and Amand Faessler. "Proton-antiproton annihilation into three mesons in flight in the 3P0 model with a planar quark diagram topology." Nuclear Physics A 503, no. 3-4 (October 1989): 737–65. http://dx.doi.org/10.1016/0375-9474(89)90438-7.

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22

Bathas, George, and W. M. Kloet. "Generalized 3P0 and 3S1 annihilation potentials for p decay into two mesons based on a simple quark model." Physics Letters B 301, no. 2-3 (March 1993): 155–58. http://dx.doi.org/10.1016/0370-2693(93)90681-7.

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23

Vasquez, Sergio O., and Colin D. Flint. "A shell model for cross relaxation in elpasolite crystals: application to the 3P0 and 1G4 states of Cs2NaY1−xPrxCl6." Chemical Physics Letters 238, no. 4-6 (June 1995): 378–86. http://dx.doi.org/10.1016/0009-2614(95)00398-n.

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24

Rahmani, B., S. Y. Liu, K. Yasuoka, H. A. Belbachir, and S. Ishii. "VUV lasing on puff metal vapor of neon-like aluminum ions produced by Z-pinch plasma." Canadian Journal of Physics 77, no. 12 (March 1, 2000): 995–1007. http://dx.doi.org/10.1139/p99-056.

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A collisional-radiative equilibrium model was developed to investigate the population inversion on metal vaporaluminum plasma. The population inversion has been establishedbetween lower3s(3P1 °, 1P1°) and upper 3p(3P0, 1S°) levels. The vacuumultra-violet lasing on neon-like aluminum ions provideswavelengths of 111.9, 143.2, and 157.3 nm. The rate of relativedensity population, between lower 3s1P1° and upper 3p3P0 levels, reaches its highest valueof 7.16 at the electron density of 1019 cm-3. Themodified expression of the optical escape factor, in the case of the Doppler profile, was introduced in the calculation of the opacityeffect on the gain magnitudes. The Holstein expressionunderestimates the optical escape factor in the region ofrelatively small thickness. The resonance radiation trapping by the 3dconfiguration drastically alters the gain values. A gain greater than 1 cm-1 was found between lasing levels 3s 3P1 ° and3p3P0. The enhancement of gain was due to the pumping of heupper level by a dielectronic recombination process from the groundstate of fluorine-like and by the inner-shell ionization processfrom excited levels of sodium-like ions.PACS No.: 52.00

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25

Matsuki, Takayuki, and Kohichi Seo. "Chiral particle/Photon emission from heavy-light mesons." International Journal of Modern Physics: Conference Series 29 (January 2014): 1460239. http://dx.doi.org/10.1142/s2010194514602397.

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Partial decay widths of the heavy-light mesons, D, Ds, B, and Bs, emitting one chiral particle (π or K) or photon γ are evaluated in the framework of a relativistic potential model. Decay amplitudes are calculated by keeping the Lorentz invariance as far as possible and use has been made of the Lorentz-boosted relativistic wave functions of the heavy-light mesons. One of predictions of our calculation is very narrow widths of a few keV for yet undiscovered Bs(0+, 1+) mesons corresponding to 2S+1LJ = 3P0 and "3P1" assuming their masses to be 5617 and 5682 MeV, respectively, as calculated in our former paper. Sizable radiative decay widths of D* or [Formula: see text] are obtained by including the 1st order corrections in 1/mQ expansion, in the unit of keV; Γ(D*0 → D0 + γ) = 9.8, Γ (D*+ → D+ + γ) = 0.71, [Formula: see text] and large radiative decay widths of DsJ are obtained compared with non-relativistic results.

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26

KUKULIN, V. I., I. T. OBUKHOVSKY, V. N. POMERANTSEV, and AMAND FAESSLER. "TWO-COMPONENT DRESSED-BAG MODEL FOR NN INTERACTION: DEUTERON STRUCTURE AND PHASE SHIFTS UP TO 1 GeV." International Journal of Modern Physics E 11, no. 01 (February 2002): 1–33. http://dx.doi.org/10.1142/s0218301302000715.

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A two-component model is developed for the intermediate-range NN interaction based on a new mechanism with an intermediate symmetric six-quark bag "dressed" by σ and other fields. To calculate the transition amplitude, the microscopic six-quark shell-model in combination with the 3P0-quark pion production mechanism is used. As a result, an effective energy-dependent NN interaction is constructed. The new quark–meson model for the NN interaction has been demonstrated to result in a new type of NN tensor force at intermediate ranges, which is crucially important for the treatment of tensor mixing at intermediate energies. The suggested model is able to describe NN phase shifts in a broad energy range from low energy up to 1 GeV, and the deuteron structure. The generalization of the model results in new spin-orbit 2N and 3N forces and new meson-exchange currents induced by intermediate dressed bag components, and also in the enhancement of a collective σ-field in nuclei.

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27

Mishra, Amruta, S. P. Misra, and W. Greiner. "In-medium decay widths of hidden and open charm vector mesons in a field theoretic model for composite hadrons." International Journal of Modern Physics E 24, no. 07 (July 2015): 1550053. http://dx.doi.org/10.1142/s0218301315500536.

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We calculate the decay widths of the charmonium states, J/ψ, ψ(3686) and ψ(3770), to [Formula: see text] pairs, as well as the decay width of D* → Dπ, in isospin asymmetric strange hadronic matter, using a field theoretical model for composite hadrons with quark constituents. For this purpose, we use the quark–antiquark pair creation term of the free Dirac Hamiltonian written in terms of the constituent quark field operators, and use explicit charmonium, D, [Formula: see text], D* and π states to evaluate the matrix elements for the charmonium as well as D* decay amplitudes. The medium modifications of the partial decay widths of charmonium to [Formula: see text] pair, arising from the mass modifications of the [Formula: see text] and the charmonium states calculated in a chiral effective model, are also included. The results of the present investigations are then compared with the decay widths computed earlier, in a model using light quark pair creation in 3P0 state. As in 3P0 model, the decay amplitude in the present model is multiplied with a strength parameter for the light quark pair creation, which is fitted from the observed vacuum decay width. The effects of the isospin asymmetry, the strangeness fraction of the hadronic matter on the masses of the charmonium states and [Formula: see text] mesons and hence on the decay widths, have also been studied. The isospin asymmetry effect is observed to be dominant for high densities, leading to appreciable difference in the decay channels of the charmonium to D+ D- and [Formula: see text] pairs. The decay width of D* → Dπ in the hadronic matter has also been calculated within the composite quark model in the present work, accounting for the medium modifications of the D and D* masses. The density modifications of the charmonium states and D(D*) mesons, which are observed to be appreciable at high densities, will be of relevance in the compressed baryonic matter (CBM) experiments at the future facility of FAIR, GSI, where charmed hadrons will be produced by annihilation of antiprotons on nuclei. The interactions of the charmonium states and D(D*) with the nuclear medium could lead to the possibility of the formation of exotic bound states of the nuclei with the (excited) charmonium states as well as with D(D*) mesons.

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28

Pardo-Botello, Rosario, Fátima Chamizo-Calero, Olga Monago-Maraña, Raquel Rodríguez-Corchado, Rosa de la Torre-Carreras, and Teresa Galeano-Díaz. "Evaluation of Hydrophilic and Lipophilic Antioxidant Capacity in Spanish Tomato Paste: Usefulness of Front-Face Total Fluorescence Signal Combined with Parafac." Food Analytical Methods 15, no. 4 (December 1, 2021): 981–92. http://dx.doi.org/10.1007/s12161-021-02175-1.

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AbstractThe hydrophilic and lipophilic antioxidant activities due to the main bioactive components present in Spanish tomato paste samples were studied, using standardized and fluorescent methods. After extraction, phenolic antioxidants (Folin-Ciocalteu method) and total antioxidant activity (TEAC assay) were evaluated, examining differences between hydrophilic and lipophilic extracts corresponding to different samples. Total fluorescence spectra of extracts (excitation-emission matrices, EEMs) were recorded in the front-face mode at two different ranges: 210–300 nm/310–390 nm, and 295–350 nm/380–480 nm, for excitation and emission, respectively, in the hydrophilic extracts. In the lipophilic extracts, the first range was 230–283 nm/290–340 nm, while the second range was 315–383 nm/390–500 nm for excitation and emission, respectively. EEMs from a set of 22 samples were analyzed by the second-order multivariate technique Parallel Factor Analysis (PARAFAC). Tentative assignation of the different components to the various fluorophores of tomato was tried, based on literature. Correlation between the antioxidant activity and score values retrieved for different components in PARAFAC model was obtained. The possibility of using EEMs-PARAFAC to evaluate antioxidant activity of hydrophilic and lipophilic compounds in these samples was examined, obtaining good results in accordance with the Folin-Ciocalteu and TEAC assays.

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29

Lee, Minju M., Ichi Tanaka, and Rohei Kawabe. "Cold gas studies of a z = 2.5 protocluster." Proceedings of the International Astronomical Union 15, S359 (March 2020): 136–40. http://dx.doi.org/10.1017/s1743921320004226.

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AbstractWe present studies of a protocluster at z =2.5, an overdense region found close to a radio galaxy, 4C 23.56, using ALMA. We observed 1.1 mm continuum, two CO lines (CO (4–3) and CO (3–2)) and the lower atomic carbon line transition ([CI](3P1-3P0)) at a few kpc (0″.3-0″.9) resolution. The primary targets are 25 star-forming galaxies selected as Hα emitters (HAEs) that are identified with a narrow band filter. These are massive galaxies with stellar masses of > 1010Mʘ that are mostly on the galaxy main sequence at z =2.5. We measure the molecular gas mass from the independent gas tracers of 1.1 mm, CO (3–2) and [CI], and investigate the gas kinematics of galaxies from CO (4–3). Molecular gas masses from the different measurements are consistent with each other for detection, with a gas fraction (fgas = Mgas/(Mgas+ Mstar)) of ≃ 0.5 on average but with a caveat. On the other hand, the CO line widths of the protocluster galaxies are typically broader by ˜50% compared to field galaxies, which can be attributed to more frequent, unresolved gas-rich mergers and/or smaller sizes than field galaxies, supported by our high-resolution images and a kinematic model fit of one of the galaxies. We discuss the expected scenario of galaxy evolution in protoclusters at high redshift but future large surveys are needed to get a more general view.

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30

Saberi, M., W. H. T. Vlemmings, E. De Beck, R. Montez, and S. Ramstedt. "Detection of CI line emission towards the oxygen-rich AGB star omi Ceti." Astronomy & Astrophysics 612 (April 2018): L11. http://dx.doi.org/10.1051/0004-6361/201833080.

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We present the detection of neutral atomic carbon CI(3P1–3P0) line emission towards omi Cet. This is the first time that CI is detected in the envelope around an oxygen-rich M-type asymptotic giant branch (AGB) star. We also confirm the previously tentative CI detection around V Hya, a carbon-rich AGB star. As one of the main photodissociation products of parent species in the circumstellar envelope (CSE) around evolved stars, CI can be used to trace sources of ultraviolet (UV) radiation in CSEs. The observed flux density towards omi Cet can be reproduced by a shell with a peak atomic fractional abundance of 2.4 × 10−5 predicted based on a simple chemical model where CO is dissociated by the interstellar radiation field. However, the CI emission is shifted by ~4 km s−1 from the stellar velocity. Based on this velocity shift, we suggest that the detected CI emission towards omi Cet potentially arises from a compact region near its hot binary companion. The velocity shift could, therefore, be the result of the orbital velocity of the binary companion around omi Cet. In this case, the CI column density is estimated to be 1.1 × 1019 cm−2. This would imply that strong UV radiation from the companion and/or accretion of matter between two stars is most likely the origin of the CI enhancement. However, this hypothesis can be confirmed by high-angular resolution observations.

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31

JIANG, YUE, GUO-LI WANG, TIANHONG WANG та WAN-LI JU. "WHY X(3915) IS SO NARROW AS A χc0(2P) STATE?" International Journal of Modern Physics A 28, № 28 (10 листопада 2013): 1350145. http://dx.doi.org/10.1142/s0217751x13501455.

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New resonance X(3915) was identified as the charmonium χc0(2P) by BaBar Collaboration, but there still seems an open question of this assignment: why its full width is so narrow? To answer this question, we calculate the Okubo–Zweig–Iizuka (OZI)-allowed strong decays [Formula: see text], where X(3915) is assigned as a χc0(2P) state, and estimate its full width in the cooperating framework of 3P0 model and the Bethe–Salpeter (BS) method using the Mandelstam formalism, during which nonperturbative quantum chromodynamics (QCD) effects of the hadronic matrix elements are well-considered by overlapping integral over the relativistic Salpeter wave functions of the initial and final states. We find the node structure of χc0(2P) wave function resulting in the narrow width of X(3915) and show the dependence of the decay width on the variation of the initial mass of X(3915). We point out that the rate of [Formula: see text] is crucial to confirm whether X(3915) is the χc0(2P) state or not.

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32

Rijken, Th A., M. M. Nagels, and Y. Yamamoto. "NIJMEGEN BARYON-BARYON INTERACTIONS FOR S = -1, -2 SYSTEMS." International Journal of Modern Physics E 19, no. 12 (December 2010): 2418–27. http://dx.doi.org/10.1142/s0218301310016892.

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We present and discuss the most recent version of the extended-soft-core (ESC) interactions. The ESC-model describes the nucleon-nucleon ( NN ), hyperon-nucleon ( YN ), and hyperon-hyperon ( YY ), in terms of meson-exchanges using (broken) SUF(3)-symmetry. In this approach to baryon-baryon ( BB ) the dynamics is derived from (i) one-boson-exchanges (OBE), (ii) two-meson-exchanges (TME), and (iii) meson-pair-exchanges (MPE), (iv) gluon-exchanges, and (v) quark-core effects. In the OBE-sector, a special feature is the importance of the axial-vector meson potentials, and the inclusion of a zero in the scalar- and axial- meson form-factors. Novelties are the inclusion of (a) odderon-exchange, and (b) special pronounced effects of the appearance of forbidden six-quark configurations. With these ingredients, a rather flexible dynamical framework is constructed. Namely, it appeared feasible to keep the parameters of the model in reasonable accordance with the predictions of the 3P0 quark-pair-creation model (QPC). This is the case for the meson- and meson-pair-baryon coupling constants and the F/(F + D)-ratio's as well. The NN , YN , and YY results for this model are rather promising. In particular, we improved the ΛN spin-orbit interaction greatly by the inclusion of (a) the Brown, Downs, and Iddings anti-symmetric spin-orbit potentials, and (b) new corrections to the MPE-potentials. Also, the special quark-core effects provide ample repulsion in the Σ+p(3S1,T = 3/2)- and ΣN(1S0,T = 1/2)-channels. The new version of the ESC-model reported here will be referred to as ESC07 henceforth.

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33

Okada, Yoko, Rolf Güsten, Miguel Angel Requena-Torres, Markus Röllig, Jürgen Stutzki, Urs Ulrich Graf, and Annie Hughes. "Velocity profiles of [CII], [CI], CO, and [OI] and physical conditions in four star-forming regions in the Large Magellanic Cloud." Astronomy & Astrophysics 621 (January 2019): A62. http://dx.doi.org/10.1051/0004-6361/201833398.

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Aims. The aim of our study is to investigate the physical properties of the star-forming interstellar medium (ISM) in the Large Magellanic Cloud (LMC) by separating the origin of the emission lines spatially and spectrally. The LMC provides a unique local template to bridge studies in the Galaxy and high redshift galaxies because of its low metallicity and proximity, enabling us to study the detailed physics of the ISM in spatially resolved individual star-forming regions. Following Okada et al. (Okada, Y., Requena-Torres, M. A., Güsten, R., et al. 2015, A&A, 580, A54), we investigate different phases of the ISM traced by carbon-bearing species in four star-forming regions in the LMC, and model the physical properties using the KOSMA-τ PDR model. Methods. We mapped 3–13 arcmin2 areas in 30 Dor, N158, N160, and N159 along the molecular ridge of the LMC in [C II] 158 μm with GREAT on board SOFIA. We also observed the same area with CO(2-1) to (6-5), 13CO(2-1) and (3-2), [C I] 3P1–3P0 and 3P2–3P1 with APEX. For selected positions in N159 and 30 Dor, we observed [O I] 145 μm and [O I] 63 μm with upGREAT. All spectra are velocity resolved. Results. In all four star-forming regions, the line profiles of CO, 13CO, and [C I] emission are similar, being reproduced by a combination of Gaussian profiles defined by CO(3-2), whereas [C II] typically shows wider line profiles or an additional velocity component. At several positions in N159 and 30 Dor, we observed the velocity-resolved [O I] 145 and 63 μm lines for the first time. At some positions, the [O I] line profiles match those of CO, at other positions they are more similar to the [C II] profiles. We interpret the different line profiles of CO, [C II] and [O I] as contributions from spatially separated clouds and/or clouds in different physical phases, which give different line ratios depending on their physical properties. We modeled the emission from the CO, [C I], [C II], and [O I] lines and the far-infrared continuum emission using the latest KOSMA-τ PDR model, which treats the dust-related physics consistently and computes the dust continuum SED together with the line emission of the chemical species. We find that the line and continuum emissions are not well-reproduced by a single clump ensemble. Toward the CO peak at N159 W, we propose a scenario that the CO, [C II], and [O I] 63 μm emission are weaker than expected because of mutual shielding among clumps.

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Serheyev, V. V., S. I. Gerasymchuk, H. V. Melnyk, and B. Yu Vоdко. "APPLICATION OF WILSON'S MODEL FOR DESCRIPTION OF PHASE EQUILIBRIUM OF VAPOR LIQUID FOR AZEOTROPIC SYSTEM ACETIC ACID – ACRYLIC ACID." Chemistry, Technology and Application of Substances 5, no. 2 (December 1, 2022): 24–29. http://dx.doi.org/10.23939/ctas2022.02.024.

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Based on data on the composition of azeotropic solutions for the acetic acid - acrylic acid system, the parameters of the semi-empirical Wilson model for temperatures 320, 330, 340, 350 K were calculated using the mathematical software package Mathcad 14 by iterations. The obtained parameters made it possible to describe the vapor-liquid equilibrium in the acetic acid-acrylic acid system: to calculate the composition of the equilibrium phases, the activity coefficients of the solution components, the separation coefficient and to construct p-x isothermal boil diagrams.

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35

Ревин, А. А., А. М. Михайлова, А. А. Конаков, В. В. Цыпленков та В. Н. Шастин. "Долинно-орбитальное взаимодействие в германии, легированном донорами V группы: количественный анализ". Физика и техника полупроводников 55, № 10 (2021): 901. http://dx.doi.org/10.21883/ftp.2021.10.51441.40.

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In the framework of the envelope function approximation, the wave functions of electrons localized at shallow donors P, As, Sb in Ge are calculated taking into account the valley-orbit coupling caused by the donor short-range potential. It is proposed an approach that makes it possible to include inter-valley mixing in the equation for a multi-component envelope function. The calculation of the effects of the valley-orbit interaction was carried out according to the perturbation theory, while the "bare" single-valley functions were found using the Ritz method. The parameters of the short-range part of the potential and the coefficient of inter-valley mixing were found individually for each donor, making it possible to obtain the best agreement with the results of experimental measurements of the energies of the singlet and triplet states. The envelope functions of the 1s(A1) and 1s(T2) states are calculated. The parameters of the valley-orbit interaction are found for each donor. It is also shown how the functions of the excited 2s, 2p0, 2p±, 3p0 states should be modified in order to remain orthogonal to the singlet and triplet functions within the framework of a more rigorous multivalley model.

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36

Bagheri, A., B. Kjeldstad, and B. Johnsen. "A case study on biomass burning aerosols: effects on solar UV irradiance, retrieval of aerosol single scattering albedo." Atmospheric Chemistry and Physics Discussions 8, no. 5 (October 6, 2008): 17987–8005. http://dx.doi.org/10.5194/acpd-8-17987-2008.

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Abstract. The aerosol optical depth (AOD) from biomass burning aerosols from eastern Europe was measured in Trondheim, Norway (63.43° N , 10.43° E) in May 2006. The event was observed as far as the Arctic. In the first part of this paper, the surface measurements of direct and global UV radiation (and retrieved AOD) are used to simulate the data using a radiative transfer model. Measured and simulated data were used to study the effect of biomass aerosol on the levels of surface UV radiation. We found reductions of up to 31%, 15% and 2% in direct, global and diffuse surface UV irradiance (at 350 nm, SZA=50°±0.5°) as compared to typical aerosol conditions. In the second part of our study, surface measurements of global and direct irradiance at five wavelength in UVB and UVA (305, 313, 320, 340 and 380 nm) were coupled with a radiative transfer model to produce values of aerosol single scattering albedo, ω. The aerosol single scattering albedo for biomass aerosols is compared to ω for background aerosols. The values of ω for biomass aerosols were 0.76 at 305 nm, 0.75 at 313 nm, 0.79 at 320 nm, 0.72 at 340 nm and 0.80 at 380 nm.

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37

Makhan'kov, V. G., Yu P. Rybakov, and Valerii I. Sanyuk. "The Skyrme model and strong interactions (On the 30th anniversary of the creation of the Skyrme model)." Uspekhi Fizicheskih Nauk 162, no. 2 (1992): 1. http://dx.doi.org/10.3367/ufnr.0162.199202a.0001.

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38

Kim, Dae-Young, Yoshiharu Nishiyama, Masahisa Wada, Shigenori Kuga, and Takeshi Okano. "Thermal Decomposition of Cellulose Crystallites in Wood." Holzforschung 55, no. 5 (September 19, 2001): 521–24. http://dx.doi.org/10.1515/hf.2001.084.

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Summary Decomposition of cellulose crystallites in wood during pyrolysis was studied by X-ray diffraction using a tension wood of Populus maximowiczii (cottonwood), which contains highly crystalline cellulose. X-ray diffraction profiles were recorded at varied temperature up to 360°C. By one-hour isothermal treatments, the cellulose crystallites did not decompose at 300°C, but completely decomposed at 340°C. The change in equatorial diffraction profile was studied by temperature scan up to 360°C and by isothermal treatment at the critical temperature of 320°C. Along with the changes by thermal expansion, the changes in diffraction diagram revealed a characteristic discrepancy between the diminishment of crystalline order and the reduction in crystallite size; i.e., the intensity of crystalline reflections diminished steadily while the crystallite size decreased much more slowly. A model of highly heterogeneous decomposition is proposed to explain this behavior.

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39

Phaiboon, Supachai, and Sastra Thanrattanukool. "An Empirically Based Model for Electric Generation of Bicycle." Applied Mechanics and Materials 701-702 (December 2014): 1210–13. http://dx.doi.org/10.4028/www.scientific.net/amm.701-702.1210.

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This paper presents an experimental study of an electric bicycle. We operated the bicycle on flat roads, uphill and downhill. The speed was categorized into slow, normal, and fast. Electrical loads were varied, step by step, for example 180, 240, 300, and 360 W. According to the observations of electrical power produced by an electric bicycle, we found that at the load of 240 W, it can produce a maximum power of 91.56 W. However, the generator can produce a maximum power of 350 W; therefore, we used a load of 360 W for studying and modeling. Finally, this model can be used to predict the electrical generation from electric bicycles as well as used for meter monitoring.

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40

Li, Jing, Long Xue, Mu Hua Liu, Ping Lv, and Lin Yuan Yan. "Determination of Moisture Content in Ginger Using PSO Combined with Vis/NIR." Advanced Materials Research 320 (August 2011): 563–68. http://dx.doi.org/10.4028/www.scientific.net/amr.320.563.

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Vis/NIR spectroscopy was used to measure the moisture content of ginger. 330 samples were separated into two groups, as training and validation. Vis/NIR reflection spectral data from 350 to 1800 nm were collected using ginger within the training and validation sets. PSO was used to establish the PLS model. In comparison to the full spectrum model (contained 1451 variables), the prediction capability was improved after using PSO for PLS models. The number of selected variables and LVs were 300 and 6, respectively. The correlation of determination in validation set (), root mean square error of prediction (RMSEP), and bias by PSO-PLS were 0.9881, 4.7827, and 0.1751.

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41

Rolin, Patrick, Didier Marquer, Michel Colchen, Charles Cartannaz, Alain Cocherie, Vincent Thiery, Jean-Michel Quenardel, and Philippe Rossi. "Famenno-Carboniferous (370-320 Ma) strike slip tectonics monitored by syn-kinematic plutons in the French Variscan belt (Massif Armoricain and French Massif Central)." Bulletin de la Société Géologique de France 180, no. 3 (May 1, 2009): 231–46. http://dx.doi.org/10.2113/gssgfbull.180.3.231.

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AbstractThe Variscan continental collision has led to the development of large strike-slip shear zones in western Europe. Our study focuses on the regional deformation and shear zone patterns in the Massif Armoricain and the French Massif Central. The synthesis of granite emplacement ages associated to granite deformation fields, allow us to propose a geodynamic model for the tectonic evolution of this part of the Variscan belt between 370 Ma – 320 Ma (Late Devonian – Namurian).After the first steps of the continental subduction-collision, leading to high temperature and anatexis associated with N-S shortening at 380-370 Ma (Frasnian to Famennian), the southern part of the Massif Armoricain and western part of French Massif Central underwent large dextral shearing along N100-N130 trending shear zones up to early Visean time. These large-scale displacements progressively decreased at around 350-340 Ma, during the first emplacements of biotite bearing granites (Moulins-les Aubiers-Gourgé massif and Guéret massif intrusions).During middle Visean times, the shortening axis direction rotated towards a NNE-SSW direction implying changes in the regional deformation field. The occurrence of N070-N100 sinistral and N110-N130 dextral conjugate shear zones within leucogranites are related to that time. Finally, new N150-N160 dextral shear zones appeared in middle to late Visean times: as for examples, the Parthenay and the Pradines shear zones in the SE Massif Armoricain and the Millevaches massif, respectively. These shear zones were conjugated to the sinistral N020 Sillon Houiller in the French Massif Central. They reflect large scale brittle continental indentation in the French Variscan belt during the middle to late Visean.

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42

Rodríguez-Rosales, Nelly Abigaíl, Félix Alan Montes-González, Oziel Gómez-Casas, Josué Gómez-Casas, Jesús Salvador Galindo-Valdés, Juan Carlos Ortiz-Cuellar, Jesús Fernando Martínez-Villafañe, Daniel García-Navarro, and Carlos Rodrigo Muñiz-Valdez. "Statistical Data-Driven Model for Hardness Prediction in Austempered Ductile Irons." Metals 12, no. 4 (April 15, 2022): 676. http://dx.doi.org/10.3390/met12040676.

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This research evaluates the effect of temperature and time austempering on microstructural characteristics and hardness of ductile iron, validating the results by means of a statistical method for hardness prediction. Ductile iron was subjected to austenitization at 950 °C for 120 min and then to austempering heat treatment in a salt bath at temperatures of 290, 320, 350 and 380 °C for 30, 60, 90 and 120 min. By increasing austempering temperature, a higher content of carbon-rich austenite was obtained, and the morphology of the thin acicular ferrite needles produced at 290 °C turned completely feathery at 350 and 380 °C. A thickening of acicular ferrite needles was also observed as austempering time increased. An inversely proportional behavior of hardness values was thus obtained, which was validated through data analysis, statistical tools and a regression model taking temperature and time austempering as input variables and hardness as the output variable, which achieved a correlation among variables of about 97%. The proposal of a mathematical model for the prediction of hardness in austempered ductile iron represents a numerical approximation which validates the experimental results at 95.20%.

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Liao, Shao Wei, Jing Wen Cao, Chung Yi Chung, Hwa Sheng Gau, Chang Gai Lee, and Wen Liang Lai. "Correlation between Fluorescent and UV Absorbance in Dissolved Organic Matter of the Effluent from the Pulp Mill." Advanced Materials Research 726-731 (August 2013): 1463–67. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.1463.

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During the interval from Oct.2011to April.2012, water samples were collected from the effluent treated by the secondary treatment of pulp mill. The measurements of EEFM (Excitation Emission Fluorescent matrix) by the fluorescent spectrometry as well as the value of UV absorbance were analyzed for water samples filtered by 0.45μm membrane filter. The EEFM information of dissolved organic matter of filtered water samples were characterized as 8 components with 89.7% of explained variation using PARAFAC model. Four substances had high loading, including the wavelength of Excitation /Emission (Ex/Em) of 360/420 nm, 280/270-430 nm, 350/430 nm and 300/420-480 nm. The fluorescent characteristic of 270/310 nm and 270/450 nm had a high correlation with UV254 value (R=0.838); however, the fluorescent intensity of 240/410 nm had a negative correlation with the value of UV200-400.

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44

Wei, Ming, Ye Tian, Lijun Wang, Yuankai Hong, Dan Luo, and Yinlin Sha. "The Emission Mechanism of Gold Nanoclusters Capped with 11-Mercaptoundecanoic Acid, and the Detection of Methanol in Adulterated Wine Model." Materials 14, no. 21 (October 23, 2021): 6342. http://dx.doi.org/10.3390/ma14216342.

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The absorption and emission mechanisms of gold nanoclusters (AuNCs) have yet to be understood. In this article, 11-Mercaptoundecanoic acid (MUA) capped AuNCs (AuNC@MUA) were synthesized using the chemical etching method. Compared with MUA, AuNC@MUA had three obvious absorption peaks at 280 nm, 360 nm, and 390 nm; its photoluminescence excitation (PLE) peak and photoluminescence (PL) peak were located at 285 nm and 600 nm, respectively. The AuNC@MUA was hardly emissive when 360 nm and 390 nm were chosen as excitation wavelengths. The extremely large stokes-shift (>300 nm), and the mismatch between the excitation peaks and absorption peaks of AuNC@MUA, make it a particularly suitable model for studying the emission mechanism. When the ligands were partially removed by a small amount of sodium hypochlorite (NaClO) solution, the absorption peak showed a remarkable rise at 288 nm and declines at 360 nm and 390 nm. These experimental results illustrated that the absorption peak at 288 nm was mainly from metal-to-metal charge transfer (MMCT), while the absorption peaks at 360 nm and 390 nm were mainly from ligand-to-metal charge transfer (LMCT). The PLE peak coincided with the former absorption peak, which implied that the emission of the AuNC@MUA was originally from MMCT. It was also interesting that the emission mechanism could be switched to LMCT from MMCT by decreasing the size of the nanoclusters using 16-mercaptohexadecanoic acid (MHA), which possesses a stronger etching ability. Moreover, due to the different PL intensities of AuNC@MUA in methanol, ethanol, and water, it has been successfully applied in detecting methanol in adulterated wine models (methanol-ethanol-water mixtures).

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45

Ben-Haim, S. A., Y. Edoute, G. Hayam, and O. S. Better. "Sodium modulates inotropic response to hyperosmolarity in isolated working rat heart." American Journal of Physiology-Heart and Circulatory Physiology 263, no. 4 (October 1, 1992): H1154—H1160. http://dx.doi.org/10.1152/ajpheart.1992.263.4.h1154.

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The present study was designed to examine the effects of acute changes in perfusate Na+ concentrations and osmolarities on left ventricular (LV) mechanics in the isolated working rat heart model. Specifically, we separated the effect of isosmotic perfusates with different Na+ concentrations on LV mechanics. After a control period during which the hearts were perfused in a working mode with a control solution of Krebs-Henseleit bicarbonate buffer (Na+ of 136 meq/l, Ca2+ of 2.6 mM, and osmolarity of 300 mosM), the hearts were subjected to different perfusates (Na+ of 96-156 meq/l and osmolarity of 240-380 mosM, using different mannitol concentrations) in a semirandom order. Peak LV pressure (PLVP), maximal time derivative of LV pressure (dP/dtmax), and cardiac output (CO) were recorded. Increasing Na+ concentrations from 96 to 156 meq/l, using isosmotic perfusates, decreased PLVP, dP/dtmax, and CO in a dose-dependent manner. The dose-dependent behavior was evident for tonicities of 240, 280, 320, and 360 but not for 380 mosM. Increasing Na+ concentration from 96 to 136 meq/l at constant perfusate tonicity (320 mosM) decreased dP/dtmax from 6,753 +/- 133 to 5,602 +/- 418 mmHg/s (P < 0.001). Rearranging the same results to examine the effect of perfusate tonicity with iso-Na+ concentration demonstrated that increasing perfusate osmolarity had a dose-dependent effect on PLVP, dP/dtmax, and CO. At a constant Na+ concentration of 116 meq/l, increasing perfusate osmolarity from 240 to 320 mosM increased dP/dtmax from 6,116 +/- 132 to 7,274 +/- 594 mmHg/s (P < 0.01). Further increase in perfusate tonicity to 380 mosM decreased dP/dtmax to 2,338 +/- 398 mmHg/s (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

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46

Yan, Xiaolu, Paul Konopka, Felix Ploeger, Aurélien Podglajen, Jonathon S. Wright, Rolf Müller, and Martin Riese. "The efficiency of transport into the stratosphere via the Asian and North American summer monsoon circulations." Atmospheric Chemistry and Physics 19, no. 24 (December 20, 2019): 15629–49. http://dx.doi.org/10.5194/acp-19-15629-2019.

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Abstract. Transport of pollutants into the stratosphere via the Asian summer monsoon (ASM) or North American summer monsoon (NASM) may affect the atmospheric composition and climate both locally and globally. We identify and study the robust characteristics of transport from the ASM and NASM regions to the stratosphere using the Lagrangian chemistry transport model CLaMS driven by both the ERA-Interim and MERRA-2 reanalyses. In particular, we quantify the relative influences of the ASM and NASM on stratospheric composition and investigate the transport pathways and efficiencies of transport of air masses originating at different altitudes in these two monsoon regions to the stratosphere. We release artificial tracers in several vertical layers from the middle troposphere to the lower stratosphere in both ASM and NASM source regions during July and August 2010–2013 and track their evolution until the following summer. We find that more air mass is transported from the ASM and NASM regions to the tropical stratosphere, and even to the southern hemispheric stratosphere, when the tracers are released clearly below the tropopause (350–360 K) than when they are released close to the tropopause (370–380 K). For tracers released close to the tropopause (370–380 K), transport is primarily into the northern hemispheric lower stratosphere. Results for different vertical layers of air origin reveal two transport pathways from the upper troposphere over the ASM and NASM regions to the tropical pipe: (i) quasi-horizontal transport to the tropics below the tropopause followed by ascent to the stratosphere via tropical upwelling, and (ii) ascent into the stratosphere inside the ASM/NASM followed by quasi-horizontal transport to the tropical lower stratosphere and further to the tropical pipe. Overall, the tropical pathway (i) is faster than the monsoon pathway (ii), particularly in the ascending branch. The abundance of air in the tropical pipe that originates in the ASM upper troposphere (350–360 K) is comparable to the abundance of air ascending directly from the tropics to the tropical pipe 10 months after (the following early summer) the release of the source tracers. The air mass contributions from the ASM to the tropical pipe are about 3 times larger than the corresponding contributions from the NASM. The transport efficiency into the tropical pipe, the air mass fraction inside this destination region normalized by the mass of the domain of origin, is greatest from the ASM region at 370–380 K. Although the contribution from the NASM to the stratosphere is less than that from either the ASM or the tropics, the transport efficiency from the NASM is comparable to that from the tropics.

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47

Horvath, John J., and Scott A. Glazier. "Fluorescence Measurement of Tetracycline in Model Fermentation Media Samples Containing Streptomyces Aureofaciens Cell Mass." Applied Spectroscopy 50, no. 3 (March 1996): 327–33. http://dx.doi.org/10.1366/0003702963906267.

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This study describes fluorescence measurements made with a fiber-optic probe on model fermentation media samples containing natural media components, high densities of Streptomyces aureofaciens cell mass, and varying concentrations of tetracycline. Tetracycline, produced commercially from S. aureofaciens, is a highly fluorescent antibiotic, and these measurements were conducted to determine the correlation between the tetracycline content in the media and the observed fluorescence of the samples. Seven separate types of media samples were examined for this study. Each medium contained a nonfluorescent base of nutrients and salts along with one of seven different natural feedstocks at a concentration of 50 g/L. In addition, the samples contained S. aureofaciens cell mass densities of 50 g/L (based on dry cell mass). Excitation wavelengths of 290 nm, 390 nm, and 413 nm were used to probe the fluorescence of the samples, and emission spectra were obtained over the wavelength ranges of 320–360 nm, 420–600 nm, and 440–600 nm, respectively. Background fluorescence observed in the region of 320–360 nm upon 290-nm excitation in the samples was due to tryptophan fluorescence contained in the S. aureofaciens cell mass and was found to decrease dramatically as tetracycline levels increased from 0 to 8000 μg/mL. Plots of fluorescence intensity at a number of emission wavelengths versus tetracycline concentration in the samples clearly revealed strong correlations.

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48

Kadafi, Muhamad. "Klasifikasi Text Judul Buku Perpustakaan Untuk Menentukan Kategori Buku Menggunakan K-Nearest Neighbor." Systemic: Information System and Informatics Journal 6, no. 2 (January 27, 2021): 47–53. http://dx.doi.org/10.29080/systemic.v6i2.1056.

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The need for information in the form of books or scientific articles at the Library of UIN Raden Fatah Palembang continues to increase. To make it easier to find book information, one of which is by classifying books based on the type of category. In classifying library book data, the Nearest Neighbor Classifier method in data mining can be combined with text data extraction techniques to classify library book title text data. The purpose of this study was to classify the text title of library books using the Nearest Neighbor Classifier to determine the type of book category. This research method uses the Nearest Neighbor Classifier data mining classification technique. The results of this study are that the highest accuracy value is found at K = 12, which is 72.50%, and the model formed can be used to classify books with labels 2x0, 150, 2x2, 400, 020, 2x1, 657, 500, 375, 302.2, 800. and cannot be used for classifying books with class labels 070, 370, 330, 300, 600, 340, 700.

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49

Zhao, Guan-Yuan, Li Zhu, Wei Liu, Jia-Cheng Zhao, and Jin-Xin Huo. "Numerical Study on the Effect of Interface Dynamic Damage of Steel‒Concrete Composite Beam Bridge Caused by High‒Frequency Impact Load." Buildings 13, no. 2 (February 16, 2023): 545. http://dx.doi.org/10.3390/buildings13020545.

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The group studs arrangement is applied to prefabricated composite beams to significantly improve construction speed. However, contact vibration exists in the unconstrained interface area of the high-speed railway composite beam during the operation period, which degrades the connecting performance of the composite beam and adversely affects the overall structure. In this study, finite element simulations of the vibration of concrete slabs and steel beams in the unconstrained interface area were carried out to obtain finite element models with damage. The effects of vibration damage on the degradation of the studs were investigated by push-out and pull-out tests using finite element simulation of the local specimen model. The macroscopic ontological models of the undamaged and previously damaged group studs were obtained. Compared with the specimen without damage, the ultimate bearing capacity of the pushed-out specimen with damage decreased by 24.8%; the ultimate slip decreased by 15%; and the stiffness decreased by 12.8%. The behavior of the pulled-out specimen with damage was almost the same as that of the specimen without damage. On this basis, a finite element model of the train–track–composite beam coupling system was established. The influence of the degradation of the connection on the coupling system with 300 km/h, 330 km/h, and 360 km/h train speeds was analyzed under the conditions of single-train driving and a two-train rendezvous. In the case of single-train travel, compared with the undamaged composite beam, the mid-span vertical displacements of the composite beams with damage increased by 13%, 8.38%, and 6.2% for train speeds of 360 km/h, 330 km/h, and 300 km/h, respectively; the transverse displacements increased by 24.2%, 15%, and 9.2%, respectively. In the case of a two-train rendezvous, the mid-span vertical displacements increased by 8.8%, 13.7%, and 12.8%, respectively; the transverse displacements increased by 26.4%, 53%, and 24.8%, respectively.

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CHEN, HAIQIANG, ROLF D. JOERGER, DAVID H. KINGSLEY та DALLAS G. HOOVER. "Pressure Inactivation Kinetics of Phage λ cI 857". Journal of Food Protection 67, № 3 (1 березня 2004): 505–11. http://dx.doi.org/10.4315/0362-028x-67.3.505.

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Inactivation curves of phage λ cI 857 inactivated by high hydrostatic pressure were obtained at three pressure levels (300, 350, and 400 MPa) in buffered media and ultrahigh-temperature 2% reduced fat milk. Pressurization of phage λ in buffered media at 300 MPa for 300 min, 350 MPa for 36 min, and 400 MPa for 8 min reduced the titer of phage λ by 7.5, 6.7, and 7.7 log, respectively. Pressurization of phage λ in milk at 300 MPa for 400 min, 350 MPa for 80 min, and 400 MPa for 20 min reduced the titer of phage λ by 5.4, 6.4, and 7.1 log, respectively. Tailing was observed in all inactivation curves, indicating that the linear model was not adequate for describing these curves. Among the three nonlinear models studied, the Weibull and log-logistic models consistently produced best fits to all inactivation curves, and the modified Gompertz model the poorest. Because there were no significant differences in the values of shape factor (n) for suspension medium buffer, we reduced the number of parameters in the Weibull model from two to one by setting n at the mean value. The simplified Weibull model produced a fit comparable to the full model. Additionally, the simplified Weibull model allowed predictions to be made at pressures different from the experimental pressures. Menstruum was found to significantly affect the pressure resistance of phage λ. Comparison of pressure inactivation of hepatitis A virus and phage λ indicated that phage λ is more sensitive to pressure than hepatitis A virus in Dulbecco's modified Eagle medium with 10% fetal bovine sera.

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