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1.
The concept of ‘D-Differentiation’, which, in the context of smooth manifolds, generalises Lie and covariant differentiation, is extended to R  ∞ -supermanifolds under the name of ‘Super D-Differentiation’. This is done by defining new (non-linear) mappings, called ‘μ-mappings’ and by relating their non-linearity to the Leibniz rule that a derivation must satisfy when it acts on a tensor product. The resulting axiomatics, which is basis-independent and coordinate-free, is then expressed in a general basis (not necessarily holonomic). Super Lie and Super covariant differentiation are, amongst others, special cases of Super D-Differentiation. In particular, the transformation rules for the connection coefficients and the commutation coefficients of non-holonomic bases are obtained. These special cases are found to be in agreement with the DeWitt Super covariant and Super Lie derivatives.   相似文献   

2.
The in situ detection and identification of environmental microorganisms is important for general microbial ecology research. In addition, the rapid detection of microbial contamination in food-processing plants is essential. The current paper proposes a method for the rapid detection and identification of microorganisms using spectral imaging. Photosynthetic and non-photosynthetic bacterial colonies with different absorption spectra in the near-infrared wavelength region were measured directly from a Petri dish. The bacterial colonies were distinguished and subsequently typed using multiple discriminant analysis. The accuracy of the detection and identification of colonies of various sizes was evaluated. The results showed that colonies with diameters of 100 and 300 μm could be detected and identified, respectively, with adequate accuracy. Moreover, using our novel application of this spectral-imaging technique, the bacterial detection and identification times were reduced by more than half and by a few weeks, respectively, compared with conventional methods.  相似文献   

3.
We have calculated the potential energy surfaces forN = Z,20Ne-112Ba nuclei in an axially deformed relativistic mean field approach. A quadratic constraint scheme is applied to determine the complete energy surface for a wide range of the quadrupole deformation. The NL3, NL-RA1 and TM1 parameter sets are used. The phenomenon of (multiple) shape coextistence is studied and the calculated ground and excited state binding energies, quadrupole deformation parameters and root mean square (rms) charge radii are compared with the available experimental data and other theoretical predictions.  相似文献   

4.
Through phase transformation kinetic analysis and experimental observation, the δ/γ transformation occurring in the non-equilibrium peritectic Fe-4.33at.%Ni alloys was systematically investigated. According to JMA solid-state transformation kinetic theory, the Time-Temperature-Transformation (TTT) curves of the δ/γ transformation in peritectic Fe-Ni alloy were calculated. On this basis, the physical correlation between the δ/γ transformation and the initial undercooling of melt (△T) was elucidated. The results indicate that the change of △T can alter not only the overall δ/γ transformation pathways but also the transformation fraction with respect to each transformation mechanism.  相似文献   

5.
We calculate the leptonic constant for the pseudoscalar ground state of the B c meson in the framework of a QCD-motivated potential model taking into account the two-loop anomalous dimension for the heavy quark current in nonrelativistic QCD as matched with full QCD.  相似文献   

6.
We show that for every set of discrete polynomials y n (x(s)) on the lattice x(s), defined on a finite interval (a, b), it is possible to construct two sets of dual polynomials z k (ξ(t)) of degrees k = s-a and k = b-s-1. Here we do this for the classical and alternative Hahn and Racah polynomials as well as for their q-analogs. Also we establish the connection between classical and alternative families. This allows us to obtain new expressions for the Clerbsch-Gordan and Racah coefficients of the quantum algebra U q (su(2)) in terms of various Hahn and Racah q-polynomials. Dedicated to the memory of our teacher and friend Arnold F. Nikiforov (18.11.1930–27.12.2005).  相似文献   

7.
A monocrystal ofFe 3 O 4 is characterized by resistance, magnetoresistance and magnetic measurements in a temperature range from 4.2 K to 350 K and magnetic field-cycling from −9 T to 9 T. The resistance measurements revealed a metal-insulator Verwey transition (VT) atT v =123.76 K with activation energy E=92.5 meV at T >T v and temperature-substitute for the activation energy below the VT,T 0=E/k B ≈3800 K within 70 K–110K. The magnetotransport results independently verified the VT at 123.70 K, with discontinuous change in the magnetic moment ΔM≈0.21 ΔM≈0.21μ B and resistance hysteresis, dependent on the magnetic field in a narrow temperature range of 0.4° around theT v . The magnetic characterization established self consistentlyT v as ≈123.67 K, the jump in the magnetization at the VT≈0.25μ B and confirmed, that the magnetocrystalline anisotropy is the main microscopic mechanism responsible for the magnetization of the monocrystal (88%) with additional natural and imposed defects contributing as 12%.  相似文献   

8.
We present in this paper the results of our calculation of five-fold differential cross-section (FDCS) for (e,3e) process on He atom in low momentum transfer and high electron impact energy in shake-off mechanism. The formalism has been developed in Born approximation using plane waves, Byron and Joachain as well as Le Sech and correlated BBK-type wave functions respectively for incident and scattered, bound and ejected electrons. The angular distribution of FDCS of our calculation is presented in various modes of coplanar geometry and comparison is made with the available experimental data. We observe that the present calculation is able to reproduce the trend of the experimental data. However, it differs in magnitude from the experiment. The present theory does not predict four-peak structure insummed mutual angle mode for lower excess ejected electron energies. We also discuss the importance of momentum transfer, post-collision interaction (PCI) and ion participation in the (e,3e) process in constant θ12 mode  相似文献   

9.
An 2 μm pulse laser based on an intracavity optical parameter oscillator (OPO) pumped by an electrooptical Q-switched 1.064 μm laser is realized. A type-II phase-matched (θ = 51.5° and φ = 0) KTP crystal and a limiting diaphragm with a diameter of 4 mm were used. The parameters of the KTP-OPO tuning curves as a function of the phase matching angles were analyzed for the case of 1.064 μm laser pumping. Experiments based on single and double KTPs for walk-off compensation were performed. An output energy of 26 mJ in the 2 μm wavelength region was obtained with a pump-to-signal conversion efficiency of 26%. The center wavelengths of the signal and idle lights were 2165.4 and 2088.6 nm with a FWHM of 3.8 and 4 nm, respectively.  相似文献   

10.
Employing the transfer matrix method, we study the electromagnetic field of one-dimensional photonic crystals with a defect inserted by pairs of μ-negative (MNG) and ε-negative (ENG) material layers. The fields within the pairs of layers and the matrix defect are independent of each other, and the whole field is their superposition. The whole defect field can be significantly enhanced by pairs of ε-negative and μ-negative layers. In contrast to the conventional defect modes, the intensity and volume of the defect field with pairs of ε-negative and μ-negative layers can be precisely adjusted.  相似文献   

11.
The problem of transition prediction for hypersonic boundary layers over a sharp cone has been studied in this work. The Mach number of the oncoming flow is 6, the cone half-angle is 5°, and the angle of attack is 1°. The conventional e N method is used, but the transition location so obtained is obviously incorrect. The reason is that in the conventional method, only the amplifying waves are taken into account, while in fact, for different meridians the decay processes of the disturbances before they begin to grow are different. Based on our own previous work, new interpretation and essential improvement for the e N method are proposed. Not only the amplification process but also the decay process is considered. The location, where by linear stability theory, the amplitude of disturbance wave is amplified from its initial small value to 1%, is considered to be the transition location. The new result for transition prediction thus obtained is found to be fairly satisfactory. It is also indicated that for the calculation of base flow, boundary layer equations can be used for a small angle of attack. Its computational cost is much smaller than those for DNS. Supported by the National Natural Science Foundation of China (Grant Nos. 10632050 and 90716007), the Special Foundation for the Authors of National Excellent Doctoral Dissertations (Grant No. 200328), and the Foundation of Liu-Hui Center of Applied Mathematics of Nankai University and Tianjin University  相似文献   

12.
The thermodynamics structural relaxation of Fe73Cu1.5Nd3Si13.5B9 amorphous alloy from room temperature to 400°C has been investigated by measuring the structure factor with in situ X-ray diffraction. The structural information of the atomic configuration such as radial distribution function (RDF) and neighbor atomic distance was gained by Fourier transformation. The research result shows that the amorphous structure remains stable in the temperature range of 30 to 400°C but exhibits distinct changes in local atomic configuration with the increase of temperature. The quantitative determination of the neighbor atomic distance suggests that the degree of short-range order changes by the temperature altering the second nearest neighbor local atomic configuration of the amorphous when structural relaxation occurs. Supported by the Natural Science Foundation of Hebei Province of China (Grant No. A2007000296), the National Natural Science Foundation of China (Grant No. 50731005), SKPBRC (Grant Nos. 2007CB616915 and 2006CB605201), and PCSIRT (Grant No. IRT0650)  相似文献   

13.
Using the loop equations we find an explicit expression for genus 1 correction in hermitian two-matrix model in terms of holomorphic objects associated to spectral curve arising in large N limit. Our result generalises known expression for F1 in hermitian one-matrix model. We discuss the relationship between F1, Bergman tau-function on Hurwitz spaces, G-function of Frobenius manifolds and determinant of Laplacian over spectral curve.Mathematics Subject Classifications. 15A52, 34M55.  相似文献   

14.
We utilize existing inclusive data on K+-meson momentum spectra of the reaction ppK + X at T p = 2.3-2.85GeV to deduce total cross-sections for ppK + Σ + n. The method used to extract those cross-sections is explained and discussed in detail. Our result for T p = 2.85GeV is consistent with the data point from a direct measurement at the same beam energy. The cross-section obtained for T p = 2.3GeV is with 13.7±2.3μb considerably smaller than the value found in a recent experiment by the COSY-11 Collaboration at a somewhat lower beam energy, indicating that the ppK + Σ + n reaction cross-section could exhibit a rather unusual energy dependence.  相似文献   

15.
A. P. Murani 《Pramana》2008,71(4):859-867
Neutron scattering data, using neutrons of incident energies as high as 2 eV, on α-Ce and α-Ce-like systems such as CeRh2, CeNi2, CeFe2, CeRu2, and many others that point clearly to the substantially localized 4f electronic state in these systems are reviewed. The present interpretation is contrary to the widely held view that the 4f electrons in these systems form a narrow itinerant electron 4f band.   相似文献   

16.
We investigate the solitons in the CP N model in terms of the decomposition of gauge potential. Based on the φ-mapping topological current theory, the charge and position of solitons is determined by the properties of the typical component. Furthermore, the motion and the bifurcation of multi-soliton is discussed. And the knotted solitons in high dimension is explored also.  相似文献   

17.
The prospects of utilizing the strangeness production reaction γdK + Λn for the determination of the Λn low-energy scattering parameters are investigated. The spin observables that need to be measured in order to isolate the Λn singlet (1 S 0) and triplet (3 S 1) states are identified. Possible kinematical regions where the extraction of the Λn scattering lengths might be feasible are discussed.  相似文献   

18.
S. Kumar  V. S. Bhasin 《Pramana》2004,63(3):509-528
The ground state wave function of11Li obtained in a three-body model proposed earlier (S Kumar and V S Bhasin,Phys. Rev. C65, 034007 (2002)) has been employed to study the probability distributions, momentum distributions and n−n correlation. Complex scaling method has been used to find the energy positions and widths of the three resonant states of11Li above the breakup threshold. The formalism is extended further to study the β-decay of11Li to two channels. One is the β-transition of11Li into a high lying excited state of11Be at 18.3 MeV, i.e.,11Be* and the second is the decay to deuteron +9Li channel. The11Be* state has been considered as a halo analog state identified as a bound three-body (9Li + n + p) system. The n-9Li interaction incorporates both the virtual state and the p-wave resonance observed experimentally. For p-9Li interaction, a Coulomb corrected separable interaction is constructed using charge indepedendence for strong interaction part. The n-p interaction is operative only in3S1 state corresponding to the isotopic spin Th =0. As a result the11Be* state has the same isotopic spin as that of9Li core, i.e.,T = 3/2. Using these realistic parameters as input and without invoking any other free parameter, the model has been used to predict the strength of the Gamow-Teller β-decay of11Li to11Be*, i.e.,Bgt = 1.5 and the value of the branching ratio to9Li + deuteron channel to be 1.3 × 10-4. These results are found to be in rather good agreement with the recent experimental findings.  相似文献   

19.
The scalar contributions to the radiative decay φK 0ˉ0 γ are studied within the framework of the Linear Sigma Model (LσM). Theoretical predictions for the associated subprocesses φf 0 γ and φa 0 γ as well as the ratio φf 0 γ/a 0 γ are also given.  相似文献   

20.
It is argued that the realization of gauge invariance condition as a consequent of cancellation between the ϕγf 0γπ 0 π 0 resonance contribution and the ϕγπ 0 π 0 background one, suggested by A.V. Anisovich et al., Yad. Fiz. 68, 1614 (2005), is misleading. The text was submitted by the author in English.  相似文献   

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