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This paper presents the first circuit that enables microsaccade function in an artificial eyeball system. Currently, the artificial eyeball is receiving increasing development in vision restoration. The main challenge is that the human eye is born with microsaccade that helps refresh vision, avoiding perception fading while the gaze is fixed for a long period, and without microsaccade, high-quality vision restoration is difficult. The proposed electronic microsaccade (E-μSaccade) circuit addresses the issue, and it is intrinsically safe because only charge-balanced stimulus pulses are allowed for stimulation. The E-μSaccade circuit adopts light-to-frequency modulation; due to the circuit's leakage and dark current of light-sensitive elements, stimulus pulses of a frequency lower than tens of Hz occur, which is the cause of flickering vision. A flicker vision prevention (FVP) circuit is proposed to mitigate the issue. The proposed circuits are designed in a 0.18 μm standard CMOS process. The simulation and measurement results show that the E-μSaccade circuit helps refresh the stimulation pattern and blocks the low-frequency output. [ABSTRACT FROM AUTHOR]

Xylose fermentation is an essential issue for lignocellulosic ethanol production, which is often inhibited by degradation products generated during biomass pretreatment. In this study, enzymatic hydrolysate of dilute acid pretreated corn stover was fermented using Zymomonas mobilis 8b. With the solid loading of corn stover increased from 5 to 24 wt.%, the xylose consumption volume decreased from 97.0 to 21.5%. The ethanol produced ranged from 7.8 to 28.6 g/L. In order to improve xylose consumption, corn slurry was integrated into the corn stover ethanol process. Integration strategies, glucoamylase dosage, and corn–corn stover mixing ratio were investigated. Results showed that introducing corn slurry into corn stover hydrolysate was an effective way to improve xylose fermentation as well as enhance ethanol titer. Specifically, when liquefied corn slurry was introduced into corn stover hydrolysate at the ratio of 1:1 and total solid loading of 24%, the xylose consumption volume exceeded 88% with the final ethanol titer reached 68.6 g/L. This study indicates that integration of the first- and the second-generation ethanol processes is beneficial to xylose fermentation. [ABSTRACT FROM AUTHOR]

The geotechnical properties of sewage sludge solidified with sulphoaluminate cement are presented. The sludge has a high water content and organic matter which is not easy to disposal. After Solidification/Stabilization (S/S), landfill disposal of sewage sludge is widely adopted in China. However, there is little research focused on the geotechnical properties of sewage sludge after S/S treatment and the impact on the landfill site is also difficult to be evaluated. To solve this problem, this paper is aimed to evaluate the basic mechanics properties of solidified materials by means of Atterberg limit, triaxial test, consolidation test and permeability test. The result showed that the strength and the hydraulic conductivity of the modified sludge was close to that of the high organic soil. By adding suitable additives, modified sludge could not only satisfy the requirement of being landfilled but also be utilized as a construction material.