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Porous Yb2O3 ceramic (55%) was pressureless sintered at 900°C for four hours in air. The crystal structure of Yb2O3 was confirmed to be cubic (Ia3¯) with c = 10.43731 Å by neutron diffraction. The spectral vibrational signature of Yb2O3 was also confirmed by micro-Raman spectroscopy. Yb2O3 is an amphoteric oxide with both acid and base character, which presents the potential for producing different hydrocarbons when used as a Fischer–Tropsch (FT) catalyst. It was found that Yb2O3 is indeed catalytically active and can be used to convert syngas (CO + H2) into useful hydrocarbons. Production of methane, ethene, and ethane was detected in the catalytic experiment performed at 500°C, but propane, propene, butane, and methanol were also detected in the experiment performed at 250°C. Hydrocarbons heavier than C4 were not observed. The limited data show deviation from a Flory–Schulz distribution suggesting additional surface processes are occurring beyond chain growth and termination.

Echolocation enables people with impaired or no vision to comprehend the surrounding spatial information through the reflected sound. However, this technique often requires substantial training, and the accuracy of echolocation is subject to various conditions. Furthermore, the individuals who practice this sensing method must simultaneously generate the sound and process the received audio information. This paper proposes and evaluates a proof-of-concept light detection and ranging (LIDAR) assist spatial sensing (LASS) system, which intends to overcome these restrictions by obtaining the spatial information of the user’s surroundings through a LIDAR sensor and translating the spatial information into the stereo sound of various pitches. The stereo sound of relative pitch represents the information regarding objects’ angular orientation and horizontal distance, respectively, thus granting visually impaired users an enhanced spatial perception of his or her surrounding areas and potential obstacles. This paper is divided into two phases: Phase I is to engineer the hardware and software of the LASS system and Phase II focuses on the system efficacy study. The study, approved by the Penn State Institutional Review Board, included 18 student volunteers, who were recruited through the Penn State Department of Psychology Subject Pool. This paper demonstrates that the blindfolded individuals equipped with the LASS system are able to quantitatively identify the surrounding obstacles, differentiate their relative distance, and distinguish the angular location of multiple objects with minimal training.