Large‐area homogeneous and uniform perovskite films are key to the mass production of perovskite solar cells, especially the flexible ones. Different from the solution‐processed preparation, herein an all‐evaporation technique is developed for both perovskite films and the hole‐transporting layer in the modules. With the two‐step strategy of active‐layer design, homogeneous large‐area perovskite films are prepared via evaporation of first PbI2 and then CH3NH3I. An 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane (F4TCNQ)‐doped 4,4′,4″‐tris(N‐(aphthalene‐2‐yl)‐N‐phenylamino)triphenylamine (2T‐NATA) hybrid hole‐transporting layer is deposited on the indium‐tin‐oxide electrode via coevaporation. A power conversion efficiency (PCE) beyond 13% is achieved with the as‐prepared flexible perovskite solar module (active area of 16.0 cm2), which exhibits both higher stability and higher efficiency than the conventional solution‐processed module using poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) as the hole‐transporting material. This novel strategy of all‐evaporation functional layers provides a feasible way for the industrialization of flexible perovskite solar cells.

The temporally and spatially resolved optical emission spectrum of Hα of a pulsed spark discharge in water was experimentally measured. The temporally and spatially resolved electron densities, along the radial direction of the spark filament, for a pulsed spark discharge in water with a conductivity of 100 µS/cm were investigated. The electron density in the spark filament was found to be in the 10 18 /cm 3 order of magnitude. The highest electron density was measured at the primary stage of the spark filament, and it decreased with time. The radial distribution of electron density increased from the center to the edge of the spark filament.

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Tight carbonate reservoirs are widely developed in Arabian Sea. The character of the reservoir indicates high heterogeneity, poor reservoir physical property and low productivity of which would lead to high Unit Technical Cost (UTC). Past drilling experiences show that thin sweet reservoirs identification is very important for field development. In this study, a new method of sweet spots prediction in tight carbonate reservoirs is carried out, and successfully used in horizontal wells design. Two main aspects of sweet spot reservoir were summarized based on this study: 1) For reservoir property prediction, multidisciplinary comprehensive research is used in this study. Seismic attributes fusion between amplitude and frequency is a main technical progress to predict the favorable reservoir. Where after, the porosity model is built by the constraint of fusion attribute and logging interpretation. 2) In terms of fluid mobility, rock type based permeability model is done to classify the flow capacity of reservoir fluid. The high permeability belt can be determined. Finally, integrate research will provide the evaluation map of sweet spots, then by which the horizontal trajectory is carried out. The study results show that sweet spots are those reservoirs with relative high porosity and high permeability compared to wall rock. Frequency and amplitude based seismic attributes fusion is a most effective way to characterize the favorable area in tight reservoir. In fluid mobility study, permeability model that constraint by lithological classification is very important to definite each flow unit of the sweet spots. Integrated analysis reveal that the sweet spots distribute in an overlap mode with poor connectivity between each reservoirs and the single reservoir thickness is only about 10~15m with an average porosity range 5%~15% and permeability range 0.1mD to 1mD. Based on the sweet spots characterization results, the horizontal well trajectory is designed to realize multi-reservoirs penetration. It is one of the best ways to maximum the well productivity, reduce the drilling risk and UTC. This study provide a new manner to predict sweet spots for tight carbonate reservoir and improve the success of horizontal drilling. The study results had been used in pilot well design in B oilfield, Abu Dhabi Offshore. The successful drilling experience can be used in the similar reservoirs of Middle East.

This paper presents a low dropout regulator (LDO) with a wide input voltage range and high power supply rejection (PSR) for hall sensor front-end circuits, which is fabricated with a 0.18 μm BCD process. A topology in which a closed-loop charge pump biases the gate of two-stage cascode NMOS pass transistors is proposed to increase immunity to Electro-Magnetic Interference (EMI) capability for automotive applications. Furthermore, a power-down protection circuit is proposed to maintain the reliability of the system, and a novel implementation of the charge pump unit is presented to improve the influence of the body effect. Detailed derivation regarding the analyses of the simplified small-signal model of the closed-loop charge pump, the loop stability, and the PSR at various frequency bands is given. Simulation and measurement results show that the proposed LDO can operate with the input voltage from 5 V to 40 V, providing up to 60 mA current drive capability, and its minimum operating voltage is 2.5 V with 10 mA load capacity. Moreover, results verify that simulated PSR is better than -81 dB at 1 kHz, and measured PSR is better than -32 dB at 10 MHz. The results confirm that the obtained parameters of line and load regulations are significantly improved to 1.86 mV/V and 1.75 mV/mA, respectively.