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In this study, suspended zinc oxide nanoparticles were used as the electron transport layer in trans-perovskite solar cells. The perovskite film was prepared by a liquid two-step method, and the crystallinity, surface morphology, and optical and photoelectric properties of the perovskite films were then investigated. The results showed that the crystallinity and film compactness of the perovskite could be controlled by the stoichiometric quantity and the perovskite formation rate. Moreover, the film morphology was affected by the annealing temperature, duration, and the amount of toluene solvent, which could be leveraged to enhance the efficiency of the device due to the charge trapping defect. The optimal annealing temperature and duration were 80 °C and 10 min, and the optimal volume ratio of isopropyl alcohol to toluene was 9:1. The highest performing perovskite solar cells in this study exhibited an energy conversion efficiency of 15.78%, a short-circuit current of 20.80 mA/cm2, an open circuit voltage of 1.10 V, and a fill factor of 0.69.

Due to the deflection of tool and workpiece induced by cutting force, there is a high complexity associated with the prediction of surface form errors in peripheral milling of thin-walled workpieces. Based on the systematic study of in-cutting chip, this paper proposes a new efficient iterative algorithm named flexible iterative algorithm (FIAL)， which is suitable for surface form errors prediction in peripheral milling of low rigid thin-walled workpiece. In FIAL, an iterative scheme for calculations of tool/workpiece (TW) deflections are developed by considering the former convergence cutting position, and in the scheme a new important variable Δ is proposed for the calculation of radial cutting depth which never been considered before. Based on FIAL and the analytical study of in-cutting chip, a double iterative algorithm (DIAL) is brought forwarded to calculate the positions and magnitude of the maximum surface form errors, which always take the peak point include in each iterative step. Comparisons of the form errors and cutting forces obtained numerically and experimentally confirm the validity of the proposed algorithms and simulation procedure. The experimental and analytical results have shown that FIAL is faster in the iteration convergent speed and more accurate than the rigid iterative algorithm in surface form errors prediction, and DIAL is proved to be valid in the maximum errors prediction.

19-Nor-17 β -hydroxy-17 α -trifluoromethyl- Δ 4 -estren-3-one 6 and its analogs 7 and 8 have been synthesized in total yields of 82%, 54% and 27%, respectively, using Me 3 SiCF 3 as a trifluoromethylating agent. The three compounds showed high affinity for rat uterus PRc.

The enhancement of k+/π+ ratio in A+B collisions comparing to p+A and/or p+p collisions at similar incident energy is predicted as a possible signal of the quark-gluon plasma formation in ultra-relativistic nucleus- nucleus collisions. Several hadronic models have been developed to see whether the enhancement can also be explained in hadronic scheme. Most of the hadronic thermal models1−4 give positive answer. However,the answers of two hadronic transport models5−6 were really opposite.