Formation around planetary displaced orbit

The paper investigates the relative motion around the planetary displaced orbit. Several kinds of displaced orbits for geocentric and martian cases were discussed. First, the relative motion was linearized around the displaced orbits. Then, two semi-natural control laws were investigated for each kind of orbit and the stable regions were obtained for each case. One of the two control laws is the passive control law that is very attractive for engineering practice. However, the two control laws are not very suitable for the Martian mission. Another special semi-natural control law is designed based on the requirement of the Martian mission. The results show that large stable regions exist for the control law.     

太阳帆日心悬浮轨道附近的相对运动

研究悬浮轨道附近的编队飞行问题，推导了悬浮轨道附近的相 对运动方程. 由于编队太阳帆之间的距离与帆到太阳的距离的比值为小量，将相对运动方程 在悬浮轨道附近线性化，得到了线性化方程. 基于该线性化方程，考虑了悬浮轨道附近的几 种编队控制方法，只需通过调节太阳帆的姿态来进行简单的控制. 其中包括一种被动编队控 制策略，该控制策略具有实现简单、稳定区域大的特点，具有很好的工程应用前景. 最后基 于非线性方程对每种编队策略进行了数值仿真验证，数值结果表明该控制方法能实现编 队.     

On the dynamics of deployment of an orbital structure with elastic elements

The object to be studied is a spacecraft with a deployable pantograph structure as a solar-battery carrier. The objective of research is to design a mathematical model of this structure taking the elasticity of pantograph elements into account. The Lagrangian formalism is followed. To model the dynamic processes in the system, a software package has been developed, which can be adapted, if necessary, to study deployable structures of other types. The behavior of the structure during deployment, collapse, and redeployment under the action of various perturbations is modeled numerically. Plots illustrating the variation of characteristic variables are presented __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 8, pp. 136–144, August 2006.     

Numerical modeling of the effect of geometric asymmetry on the damping aerodynamic characteristics of supersonic sectional flight vehicles

A method for calculating the steady inviscid supersonic flow past equivalent bodies is applied to the analysis of the time-dependent aerodynamic characteristics of sectional flight vehicles with an asymmetric rear stabilizer. The stabilizer asymmetry can be caused by either its deflection or a change in its shape due to heat-shield coating removal, boundary layer displacement thickness, developed separation flow zones, local deformations, or other distortions in the baseline form. Amathematical apparatus for modeling asymmetric sectional configurations by means of ruled surfaces with arbitrary contours of the reference cross-sections is developed. The uniform perfect-gas M_∞ = 6 flow past sectional vehicles performing plane oscillations about the zero angle of attack is calculated (the adiabatic exponent γ = 1.4). The calculated results demonstrate the effect of various asymmetries in the body shape on the aerodynamic coefficients.     

Quantum chemical study of a new class of sensitisers: influence of the substitution of aromatic rings on the properties of copper complexes

We present a computational study of new copper complexes with potential applications as sensitisers for solar cells. The applied methodology for this study is based on the density functional theory (DFT) and time-dependent DFT, using the B3LYP, PBE0 and M06 functionals with the LANL2DZ (D95V on first row), 6-31G(d,p), 6-311G(d,p) and DZVP basis sets. Optimised molecular structure, the absorption spectra, the molecular orbitals energies and the chemical reactivity parameters that arise from conceptual DFT were calculated. Solvent effects have been taken into account by an implicit approach, namely, the polarisable continuum model (PCM), using the non-equilibrium version of the integral equation formalism of the PCM model. Interesting work for experimentalists in the dye sensitised solar cells’ field.     

Nanosilver surface plasmon response enhanced the photovoltaic performance of organic solar cells

Nanosilver island thin films with different thickness were synthesized by vacuum vapor deposition between ITO and PEDOT:PSS for organic solar cells, forming the structure of ITO/AgNPs layer/PEDOT:PSS/P3HT:PCBM/LiF/Al. Surface morphology and UV–vis absorption spectrum were investigated by AFM and UV–vis scanning spectrophotometer. It was found that after adding the nanosilver film, the optical properties of the device were enhanced with increasing the thickness of nanosilver island films. When the thickness of nanosilver thin films is 3.0 nm, the most significant surface plasmon response and red-shift of the resonance absorption peak appeared. Meanwhile, short circuit current density of the device increased from 9.93 mA/cm² to 12.98 mA/cm², the fill factor increased from 49.35% to 52.79% and the power conversion efficiency increased from 3.05% to 4.01%. These results provided a theoretical guidance to optimize the design and increase the performance of solar cells.     

Theory study on the properties of thiadiazole polymer donors for organic solar cells

In this work, the properties of [1,2,5] thiadiazolo [3,4‐c] pyridine ‐alt‐cyclopenta [2,1‐b:3,4‐b′] dithiophene (PT‐CDT) and [1,2,5] thiadiazolo [3,4‐c] pyridine‐6‐carbonitrile‐alt‐cyclopenta [2,1‐b:3,4‐b′] dithiophene (PCNT‐CDT) as donors were investigated by means of Density Functional Theory. The electronic properties and optical absorption properties were discussed, and hole‐transfer properties of donors were studied by Marcus electron transfer theory. The results indicate that the linear structure of PCNT‐CDT and PT‐CDT is more stable than the spiral structure of PCNT‐CDT and PT‐CDT; the absorption peak in visible region of PCNT‐CDT is stronger and wider, and the absorption spectrum is more matchable to solar spectrum than PT‐CDT, while the maximum absorption wavelength of PCNT‐CDT has an obvious red shift; the two designed materials show strong intramolecular and intermolecular charge transfer properties; PCNT‐CDT owns a large open‐circuit voltage and low reorganization energy, as well as high hole mobility. Therefore, the newly designed PCNT‐CDT can be a potential donor material of organic solar cell. Copyright © 2013 John Wiley & Sons, Ltd.     

cis‐substituted tetraethynylporphyrin derivatives for small molecule organic solar cells

A 5,10‐Bis(phenylethynyl)‐15,20‐bis(triisopropylsilylethynyl)porphyrin (cis‐TIPSTEP) was synthesized by using phenylethynyl dipyrromethane and triisopropylsilylpropynal through scrambling of the ethynyl substituents. X‐ray crystallographic structures of cis‐TIPSTEP, 5‐phenylethynyl‐10,15,20‐tris(triisopropylsilylethynyl)porphyrin, and 5,10,15,20‐tetrakis(triisopropylsilylethynyl)porphyrin were determined in order to study the packing structure; cis‐TIPSTEP exhibited good π‐overlap and parallel π‐stacking structures. 5,10‐Bis(phenylethynyl)‐15,20‐bis(triisopropylsilylethynyl)porphyrinato magnesium (II) (Mg‐cis‐TIPSTEP) was synthesized for the use in small molecule organic solar cells, which gave power conversion efficiency of 1.5% with short‐circuit current density of 4.5 mA/cm², open‐circuit voltage of 0.83 V, and fill factor of 0.39. Copyright © 2013 John Wiley & Sons, Ltd.     

MoO3/Ag/MoO3 top anode structure for semitransparent inverted organic solar cells

In this study, we fabricated semitransparent polymeric solar cells with an inverted structure, with the structure being indium tin oxide (ITO)/cesium carbonate (Cs₂CO₃)/poly(3-hexylthiophene) (P3HT):1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C61(PCBM)/transparent multilayer. The structure of the transparent multilayer (DMD multilayer), which acted as the anode, was MoO₃ (1–40 nm)/Ag (10 nm)/MoO₃ (0–80 nm). The inner MoO₃ layer showed a great performance changes depending on the variation of thickness, while the outer MoO₃ layer showed relatively slight changes. The best performance was observed with the of anode DMD multilayer thickness of 6/10/40 nm and with the illumination from the ITO side in organic solar cell devices. High performance result was observed in high reflectance and low transmittance of the DMD layer.     

硅片及其太阳电池的光衰规律研究

采用氙灯模拟太阳光源,将光强调至1000 W/m2,研究常规太阳能级单晶硅片、多晶硅片和物理提纯硅片的原片、去损减薄片、热氧化钝化片、双面镀氮化硅(SiN x:H)膜钝化片、碘酒钝化片以及太阳电池的光衰规律.利用WT-2000少子寿命测试仪以及太阳电池I-V特性测试仪分别对硅片的少子寿命和太阳电池的I-V特性参数随光照时间的变化进行了测试.结果表明:所有硅片以及太阳电池在光照的最初60 min内衰减很快随后衰减变慢,180 min之后光衰速率变得很小,几乎趋于零.