420 research outputs found
Correlation between chemical composition, EHGE and TME of corn for ducks
Correlations between chemical composition, enzymatic hydrolysate gross energy (EHGE), and true metabolizable energy (TME) of corn for ducks were investigated. Twenty-two corn samples were collected from various regions in 11 provinces of China. The crude protein (CP), ether extract (EE), neutral detergent fibre (NDF), Ash, gross energy (GE), dry matter (DM), amylopectin (AP), amylose (AM), total starch (TS), and AP/AM were determined for each sample. Five of the samples of corn were chosen at the mean, mean ± 1 standard deviation (SD), and mean ± 2 SD based on AP/AM. The EHGE of these samples was analysed using the pepsin-artificial small intestinal fluid enzymatic method. These five samples were also force-fed to male Cherry Valley ducks to assay their TME. Finally, correlation analyses were performed, and regression equations were established. Ash content, GE, and TS were highly related to EHGE. Univariate prediction equations were EHGE = 11.8566Ash-0.0421 (P <0.05), EHGE = 0.1535GE1.5642 (P <0.05), and EHGE = 0.1020TS1.1561 (P <0.05). The total starch, AP/AM, and ash of the chemical compositions were highly related to TME. The corresponding univariate regression equations were TME = 21.9355TS-0.0910 (P <0.05), TME = 15.6590AP/AM-0.0559 (P <0.05), and TME = 15.0778Ash0.0442 (P <0.05). The mean EHGE was equivalent to 78.5% of TME, but their correlation coefficient was low. In conclusion, chemical composition was predictive of EHGE and TME of corn samples for ducks, but the correlation of EHGE and TME was low
Keywords: Cherry Valley duck, amylopectin, amylose, true metabolizable energ
Surface Strengthening Behavior of Magnesium Alloy with Laser Thermal Loading under Rapid Cooling
Laser surface strengthening had been performed on an AZ31B magnesium alloy, while the sample was rapidly cooled in liquid nitrogen. Surface strengthening behavior and mechanism were investigated. Because of strengthening mechanisms of fined grains, super solid solution, dislocation and the existence of the amorphous structure, microhardness, wear resistance and fracture toughness of magnesium alloy was greatly improved. Because of the rapid heating and cooling loading of laser, the grains of the strengthening layer were greatly refined, and amorphous structure was formed. And there were more dislocations in the strengthening layer rather than in the substrate. Furthermore, distortion of lattice caused by large numbers of Al element dissolved into α-Mg also increased the resistance to dislocation motion.Выполнено лазерное поверхностное упрочнение образца из магниевого сплава AZ31B с его одновременным быстрым охлаждением в жидком азоте. Исследованы характер и механизм поверхностного упрочнения. Благодаря механизмам уменьшения размеров зерен и возникновения твердого суперрасплава, а также их влиянию на движение дислокаций и образование аморфной структуры имеет место значительное повышение микротвердости, износостойкости и вязкости разрушения магниевого сплава. Ускоренные режимы нагрева лазером и охлаждения в жидком азоте способствовали уменьшению размеров зерен в упрочненном поверхностном слое и формированию аморфной структуры. Большинство дислокаций было обнаружено в упрочненном слое, а не в подложке. Искажение кристаллической решетки, вызванное высокой концентрацией алюминия, растворенного в α-Mg фазе, также повышает устойчивость данного сплава к движению дислокаций.Виконано лазерне поверхневе зміцнення зразка з магнієвого сплаву АZ31B з його одночасним швидким охолодженням у рідкому азоті. Досліджено характер і механізми поверхневого зміцнення. Завдяки механізмам зменшення розмірів зерен і виникнення твердого суперрозплаву та їх впливу на рух дислокацій і виникнення аморфної структури має місце значне підвищення мікротвердості, зносостійкості і в язкості руйнування магнієвого сплаву. Прискорені режими нагрівання лазером і охолодження у рідкому азоті сприяли зменшенню розмірів зерен у зміцненому поверхневому шарі і формуванню аморфної структури. Більшість дислокацій було виявлено у зміцненому шарі, а не в підкладці. Спотворення кристалічної решітки в результаті високої концентрації алюмінію, що розчиняється в α-Mg фазі, також збільшує стійкість даного сплаву до руху дислокаці
Cooperative spontaneous emission in nonuniform media
The subject of this paper is modification of cooperative spontaneous emission
by a nonuniform medium, with nonuniform distributions of electromagnetic field.
A brief analyzis is presented and it is postulated, that if spontaneous
emission from an atom is strongly suppressed, cooperative emission with another
atom may be a preferred emission channel and counteract the suppression.Comment: The final publication is available at http://www.epj.or
Existence and uniqueness of solutions for systems of fractional differential equations with Riemann–Stieltjes integral boundary condition
In this article, we first establish an existence and uniqueness result for a class of systems of nonlinear operator equations under more general conditions by means of the cone theory and monotone iterative technique. Furthermore, the iterative sequence of the solution and the error estimation of the system are given. Then we use this new result to study the existence and uniqueness of the solution for boundary value problems of systems of fractional differential equations with a Riemann–Stieltjes integral boundary condition in real Banach spaces. The results obtained in this paper are more general than many previous results and complement them
Search for Invisible Decays of and in and
Using a data sample of decays collected with the BES
II detector at the BEPC, searches for invisible decays of and
in to and are performed.
The signals, which are reconstructed in final states, are used
to tag the and decays. No signals are found for the
invisible decays of either or , and upper limits at the 90%
confidence level are determined to be for the ratio
and for . These are the first
searches for and decays into invisible final states.Comment: 5 pages, 4 figures; Added references, Corrected typo
Observation of Two New N* Peaks in J/psi -> and Decays
The system in decays of is limited to be
isospin 1/2 by isospin conservation. This provides a big advantage in studying
compared with and experiments which mix
isospin 1/2 and 3/2 for the system. Using 58 million decays
collected with the Beijing Electron Positron Collider, more than 100 thousand
events are obtained. Besides two well known
peaks at 1500 MeV and 1670 MeV, there are two new, clear peaks in
the invariant mass spectrum around 1360 MeV and 2030 MeV. They are the
first direct observation of the peak and a long-sought "missing"
peak above 2 GeV in the invariant mass spectrum. A simple
Breit-Wigner fit gives the mass and width for the peak as MeV and MeV, and for the new peak above 2 GeV
as MeV and MeV, respectively
Semileptonic decays of , , and
Stimulated by recent observations of the excited bottom-strange mesons
and , we calculate the semileptonic decays , which is relevant for the exploration of the
potential of searching these semileptonic decays in experiment.Comment: 11 pages, 3 figures, 9 tables. More discussion added, some
descriptions changed. The version to appear in EPJ
Dynamics of multipartite quantum correlations under decoherence
Quantum discord is an optimal resource for the quantification of classical
and non-classical correlations as compared to other related measures. Geometric
measure of quantum discord is another measure of quantum correlations.
Recently, the geometric quantum discord for multipartite states has been
introduced by Jianwei Xu [arxiv:quant/ph.1205.0330]. Motivated from the recent
study [Ann. Phys. 327 (2012) 851] for the bipartite systems, I have
investigated global quantum discord (QD) and geometric quantum discord (GQD)
under the influence of external environments for different multipartite states.
Werner-GHZ type three-qubit and six-qubit states are considered in inertial and
non-inertial settings. The dynamics of QD and GQD is investigated under
amplitude damping, phase damping, depolarizing and flipping channels. It is
seen that the quantum discord vanishes for p>0.75 in case of three-qubit GHZ
states and for p>0.5 for six qubit GHZ states. This implies that multipartite
states are more fragile to decoherence for higher values of N. Surprisingly, a
rapid sudden death of discord occurs in case of phase flip channel. However,
for bit flip channel, no sudden death happens for the six-qubit states. On the
other hand, depolarizing channel heavily influences the QD and GQD as compared
to the amplitude damping channel. It means that the depolarizing channel has
the most destructive influence on the discords for multipartite states. From
the perspective of accelerated observers, it is seen that effect of environment
on QD and GQD is much stronger than that of the acceleration of non-inertial
frames. The degradation of QD and GQD happens due to Unruh effect. Furthermore,
QD exhibits more robustness than GQD when the multipartite systems are exposed
to environment.Comment: 15 pages, 4 figures, 4 table
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