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High voltage direct current (HVDC) transmission benefits cross-provincial long-distance transmission and nonconcurrent interconnection between frameworks than electric power transmission. Due to the different nature of electric power transmission, the power system analysis has evolved from a pure AC power system to a hybrid AC/DC power system. The high-power electrical energy is transmitted under the premise of the hybrid AC/DC power system. It is necessary to monitor the power flow of the hybrid AC/DC power system to avoid substantial economic losses. Therefore, studying the power flow for such a massive power system is crucial. This paper is proposed to apply the secant method and the unified method to analyze the power flow distribution for the hybrid AC/DC power system. First, the initial value is optimized by using the secant method. Then the optimized value is acted as an initial condition used in the unified method. The results show the combined method’s effectiveness and practicability through the power flow analysis using the IEEE 14-Bus system as the simulation model.

Data for σ(θ) and Ay(θ) previously obtained at the Triangle Universities Nuclear Laboratory for 120Sn(n, n) are combined with other measurements of σ(θ) and Ay(θ) to create an elastic-scattering database from 9.9 to 24 MeV. In addition, relatively recent high-accuracy measurements of the neutron total cross section σT for Sn from 5 to 80 MeV are combined with earlier σT data to form a detailed σT database from 0.24 to 80 MeV. All of these data are analysed in the framework of a dispersive optical model (DOM). The DOM is extended to negative energies to investigate properties of single-particle and single-hole bound states. The DOM also is used in calculations of compound-nucleus contributions to σ(θ), so that DOM predictions can be compared to σ(θ) measurements. Excellent agreement is obtained for the entire set of scattering data from 0.4 to 24 MeV, and for σT values from 0.05 to 80 MeV. Calculations of bound-state quantities are compared to values derived from experiment for energies down to −15 MeV. Reasonable agreement for the binding energies is achieved, while the predicted spectroscopic factors disagree somewhat with the values found in stripping and pickup experiments. Finally, the DOM is modified to investigate two features (volume absorption that is asymmetric about the Fermi energy and zero absorption in the vicinity of the Fermi energy) that have been ignored in many DOM models. These modifications have little effect on the agreement of the calculations with the scattering data or with the bound-state quantities.

This study attempts to investigate the performance and internal flow characteristics of a cross-flow turbine by guide vane angle. In order to improve the performance of a cross flow turbine, the paper presents a numerical investigation of the turbine with air supply and discusses the influence of variable guide vane angle on the internal flow. A newly developed air supply from air suction Hole is adopted. To investigate the performance and internal flow of the cross-flow turbine, the CFD software based on the two-phase flow model is utilized. The numerical grids are made in two-dimensional geometry in order to shorten the time of two-phase calculations. Then a series of CFD analysis has been conducted in the range of different guide vane angle. Moreover, local output power is divided at different stages and the effect of air layer in each stage is examined.

Construction of a 40 T hybrid magnet system is in progress at the High Magnetic Field Laboratory, Chinese Academy of Sciences. The present design concept includes an 11 T superconducting magnet with a room temperature bore of 580 mm, a 29 T resistive magnet with a clear bore of 32 mm, and a 26 T resistive magnet with a clear bore of 50 mm. The total maximum field on axis in the 32 mm bore is 40 T, and in the 50 mm bore it is 37 T. The 11 T superconducting magnet will use a cable-in-conduit conductor (CICC). The high field magnet is made from Nb3Sn superconductor, and the low field magnet is made from NbTi superconductor. This paper describes the design concept of the cable-in-conduit conductor and the mechanical analysis of the jacket.

Differential elastic and inelastic (4.44 MeV) neutron scattering cross sections from 12C are presented at 15.6, 16.8 and 17.3 MeV. The existing 18.2 MeV differential cross-section data were combined with newly measured analysing power data to parametrise neutron scattering at this energy. The 12C recoil kerma factors were calculated and reaction cross sections were obtained from a phase-shift analysis and coupled-channel analyses in the 15.6-18.2 MeV energy range.

The analysing power Ay( theta ) for 12C(n,n)12C elastic scattering and for inelastic scattering to the first excited state (Jpi =2+, Q=-4.44 MeV) of 12C was measured at 18.2 MeV. A pulsed polarised neutron beam was produced via the 2H(d,n)3He polarisation transfer reaction. The Ay data, together with published cross sections, were analysed in the framework of the spherical optical model and in the coupled-channels formalism. A phase-shift analysis at 18.2 MeV gives supporting evidence for a broad 5/2+ resonance. The 12C recoil kerma factors and values for the n+12C reaction cross section were deduced and compared with previous estimates and predictions.

Amorphous silicon films, prepared by glow discharge, LPCVD and electron beam evaporation, were crystallized by incoherent light from an arc discharge. These samples had a wide range of dark conductivities at room temperature varying from 10-11 to 10-6 (Ω·cm)-1 before crystallization, but after crystallization the values converge to 10-5–10-4 (Ω·cm)-1. It is suggested that grain boundaries resulted in an amorphous-like density-of-state distribution, with a maximum at about 0.30±0.05 eV below the conduction band. It is demonstrated that for doped films crystallization effectively activates the dopants.