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Parylene C, an emerging material in microelectromechanical systems (MEMS), is now widely applied to neural prosthesis devices, such as artificial retinal implants, due to its well-known biocompatibility and ability to be easily patterned by oxygen plasma etching. This work presents a flexible parylene-based microelectrode array（MEA）using MEMS techniques aiming for the chronic subretinal stimulation. The MEA was successfully manufactured and inserted into the subretinal space of a rabbit eye by a novel surgical operation. Optical Coherence Tomography(OCT) showed that a chronic implantation of parylene-based electrode arrays in the rabbit retina over a three month follow-up period demonstrated that the present chip system has a good biocompatibility with the subretinal organs without obvious damages.

Planar Schottky contact and various trench Schottky contacts have been integrated into the edge termination region of a 4H-SiC trench metal-oxide-semiconductor field-effect-transistor (MOSFET). The forward and reverse characteristics of various design splits have been benchmarked to determine the optimum method of the Schottky contact integration. As a result, the trench Schottky diode with Schottky metal contact in both the planar surface and the trench sidewall surface has been able to offer the best performance.

Power line communication is popular at indoor communication and smart home applications, which face a harsh using condition that is of bad impedance match, large signal attenuation, unexpectable noise and channel high time variation. These difficulties set a high threshold for power line communication technology and improve the communication channel simulation to an important place. To predetermine the performance of power line communication productions, a narrow-band communication simulation platform was developed. This platform is based on low voltage communication channel model, and can update the system parameters using on site measured data, which could get a match with the real application environment. Main channel characteristics, such as noise, signal attenuation and frequency respond could be simulated on this platform. Noise generation frequency range of this platform is 0~120MHz, attenuation frequency range is 0~4GHz and attenuation range is 0~120dB. All performance indexes can well cover the measurement boundary of power line communication.

Phthalazinone structure contained phthalaazione ether sulfone ketone (PPESK) is a kind of excellent engineering plastic with high temperature resistance and resolvability. In this paper, SC-CO₂ was used as foaming agent to prepare PPESK foams by temperature rising method. The influence of technological conditions like foaming time, foaming temperature and saturation pressure on cell density and cell morphology was discussed and analyzed.

Shallow inland water resources has a large potential for development. To Jiyang shallow groundwater for example, through the regular ion-test analysis, Piper diagram and hydrogeochemical characteristics, the results show that: (1) The type of chemistry of shallow groundwater inland were Cl·SO₄-Mg·Na·Ca; (2) The salt water area is relatively fixed, there is no expansion or decreasing trend; (3) The level flow of shallow groundwater is slow and water rock interaction is strong, that is not conducive to the shallow groundwater quality improvement, changing the runoff conditions of shallow groundwater is essential way for shallow groundwater resources exploitation.

In order to study the toxicity mechanism of plant VOCs of four kinds of terpene monomers(α-terpineol,α-pinene,β-pinene,1,8-cineole), the activities of acetylcholinesterase in Zophobas morio larvae were treaded with spectrophotometer at different time (12h, 24h, 36h, 48h). The results showed that four kinds of terpene monomers (α-terpineol, β-pinene, α-pinene, 1,8-cineole) had high biological activity in Zophobas morio, which can inhibit the activity of acetylcholinesterase(AchE) effectively．

Through the analysis of harmonics caused by transformer, capacitor, electromagnetic voltage transformer and other accident, harmonics is an important indicator of power quality, which has been included in the “pollution" of power grid is found. In order to understand the harmonic, this paper from the concept of quality of electric energy, and then gradually extended to the field of harmonics. This paper firstly introduces the various reasons and equipment may produce harmonic, Secondly, illustrate harm of harmonic to operation of transformers, capacitors, electromagnetic voltage transformers and other electrical equipment, let more people know and understand the relevant knowledge of the harmonic, In order to save technical force and provide scientific basis for future effective harmonic.

The commercial success of silicon carbide (SiC) diodes and MOSFETs for the automotive industry has led many in the field to begin developing ultra-high voltage (UHV) SiC insulated gate bipolar transistors (IGBTs), rated from 6 kV to 30 kV, for future grid conversion applications. Despite this early interest, there has been little work conducted on the optimal layout for the SiC IGBT, most early work seeking to overcome difficulties in fabricating the devices without a P+ substrate. In this paper, numerical TCAD simulations are used to examine the link between the carrier lifetime of SiC IGBTs and their short circuit capability. For the planar devices, simulations show that increasing carrier lifetime from 1 to 10 μs, has not only a profound effect reducing on-state losses, but also increases short circuit withstand time (SCWT) by 39%. Two retrograde p-well designs are also investigated, the optimal device for SCWT having a 100 nm channel region of 5×10¹⁶ cm^-3, with this increasing to a peak value of 2×10¹⁸ cm^-3, in a 700 nm region beneath the channel.

Concrete is the most consumed building material worldwide today, which durability has been paid close attentions for a long time. Currently，the design lifetime of many buildings is over 100 years. At present, many projects adopt preservatives to extend the durability of concrete. the paper makes contrastive studies on mechanical properties, ASTM flux, RCM chloridion diffusion, Permit in situ chloridion permeability, Autoclam water absorption, and freezing & thawing resistance between preservatives-added and non-preservative concretes at different typical strengths; and concludes correlations between the preservatives at different strengths and the durability of concrete, thus to evaluate the influence of various preservatives on the durability of high-performance concrete.

A novel method to automatically generate the depth map is presented, when the depth maps of reference images located before and after the target image in the same image sequence are given. A novel grid dividing method and a joint feature response model are proposed to adaptively select trace points, and an image deformation algorithm is given to track depth maps with the trace points. Experimental results show that the proposed method can generate depth maps effectively and accurately, which can meet the industrial needs in 2D-3D conversion.