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In contrast to the conventional monofacial photovoltaic (PV) modules, bifacial PV modules yield more electrical energy by utilizing the reflected or scattered light from the ground and surroundings. The energy generation efficiency of bifacial modules is determined by both the front-side and the rear-side output power. In this study, we compared the IV parameters as well as field performance of different module structures to further realize the influencing factors dominating the energy gain of bifacial modules. Our results show that the glass/glass bifacial modules encapsulated with bifacial solar cells provide over 6% more energy yield compared to the glass/backsheet monofacial modules encapsulated with regular monofacial solar cells. Due to optical enhanced effects of a reflective coating on the rear glass, the energy yield gain of bifacial modules can be increased to above 10%, even though the bifaciality factors were reduced from 72% to 64%. Our study indicates that enhancing the front-side output power of bifacial modules produces more benefits.

The present paper reports Cu and Cu(Mn) films prepared layer-by-layer using an electrochemical atomic layer deposition (ECALD) method. The structure and properties of the films were investigated to elucidate their suitability as Cu interconnects for microelectronics. Previous studies have used primarily a vacuum-based atomic layer deposition to form a Cu metallized film. Herein, an entirely wet chemical process was used to fabricate a Cu film using the ECALD process by combining underpotential deposition (UPD) and surface-limited redox replacement (SLRR). The experimental results indicated that an inadequate UPD of Pb affected the subsequent SLRR of Cu and lead to the formation of PbSO 4 . A mechanism is proposed to explain the results. Layer-by-layer deposition of Cu(Mn) films was successfully performed by alternating the deposition cycle-ratios of SLRR-Cu and UPD-Mn. The proposed self-limiting growth method offers a layer-by-layer wet chemistry-based deposition capability for fabricating Cu interconnects.

This paper is concerned with the optimal linear filtering problem for systems with incomplete measurements and white multiplicative noises. The measurement data suffers from one-step delay and packet dropouts in transmission from the sensor to the filter. At each moment, the filter may receive one or two data packets or nothing. First, the multiplicative noises are transferred to the additive noises. Then, a new augmented state vector with a lower order is proposed. Based on the new state vector, the optimal linear filter is obtained. Moreover, the steady-state behavior of the proposed filter is studied.

The hydrodynamic problem of oblique impact of a water cone on a solid wall is investigated by the three dimensional (3D) velocity potential flow theory. The time stepping method is used in a stretched coordinate system to track the moving water surface where the fully nonlinear dynamic and kinematic boundary conditions are satisfied through an improved Eulerian method. In particular the free surface elevation and potential variation are updated at a given azimuth in each θ plane of the cylindrical coordinate system, to overcome the numerical difficulties caused by the complex variation of the 3D curved free surface. Remeshing and smoothing are applied regularly along the intersection lines of the free surface and each θ plane. Detailed convergence study with respect to a time step and element size has been undertaken and high accuracy has been achieved. Extensive simulations are made for perpendicular and oblique impacts. Detailed results for pressure and free surface profile are provided.

In contrast to the weak interaction commonly found between low valence metals such as Ca and a polymeric material, considerable changes in photoelectron spectroscopy have recently been observed in experiment after evaporating Ca onto poly (9,9-dioctylfluorene) (PFO). Here, by performing calculations using Moller–Plesset perturbation theory, we show that the Ca/PFO interaction depends on the number of Ca atoms attaching to the PFO oligomer unit. A strong interaction could take place when two Ca atoms were adsorbed at a PFO unit. Further, the resulted PFO deformation and the modified frontier orbitals could be recovered when oxygen was further added.

With quantum chemical PM3/FF method, effects of strucure and substituents -NO 2 and -NH 2 on nonlinear optical properties of polypyridinopyridine(PPY) were discussed. The results showed that the β and y values were -5.54 x 10 -29 esu and -1.544 x 10 -32 esu, respectively. In three stable structures of equal-bond length structure (a), cis-structure (b) and trans-structure (c), the β and y values of (a) and (c) is larger than (b). More specially, β and y values of (c) increased promptly as the number of repeat unit increased. When the number of unit was over four, (c) gave the biggest β and y. In structures of PPY substituted by NO 2 and NH 2 , the effects of pull-push electron and π-electron delocalization became stronger, β increased effectively to about 1.6 x 10 -27 esu. PPY is a promising candidate of nonlinear optical (NLO) materials.