Interferometric gravitational wave observatories recently launched a new field of gravitational wave astronomy with the first detections of gravitational waves in 2015. The number and quality of these detections is limited in part by thermally induced vibrations in the mirrors, which show up as noise in these interferometers. One way to reduce this thermally induced noise is to use low temperature mirrors made of high purity single-crystalline silicon. However, these low temperatures must be achieved without increasing the mechanical vibration of the mirror surface or the vibration of any surface within close proximity to the mirrors. The vibration of either surface can impose a noise inducing phase shift on the light within the interferometer or physically push the mirror through oscillating radiation pressure. This paper proposes a system for the Laser Interferometric Gravitational-wave Observatory (LIGO) to achieve the dual goals of low temperature and low vibration to reduce the thermally induced noise in silicon mirrors. Experimental results are obtained at Stanford University to prove that these dual goals can be realized simultaneously.

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Data visualization has become an increasingly important means of effective data communication and has played a vital role in broadcasting the progression of COVID-19. Accessible data representations, on the other hand, have lagged behind, leaving areas of information out of reach for many blind and visually impaired (BVI) users. In this work, we sought to understand (1) the accessibility of current implementations of visualizations on the web; (2) BVI users’ preferences and current experiences when accessing data-driven media; (3) how accessible data representations on the web address these users’ access needs and help them navigate, interpret, and gain insights from the data; and (4) the practical challenges that limit BVI users’ access and use of data representations. To answer these questions, we conducted a mixed-methods study consisting of an accessibility audit of 87 data visualizations on the web to identify accessibility issues, an online survey of 127 screen reader users to understand lived experiences and preferences, and a remote contextual inquiry with 12 of the survey respondents to observe how they navigate, interpret and gain insights from accessible data representations. Our observations during this critical period of time provide an understanding of the widespread accessibility issues encountered across online data visualizations, the impact that data accessibility inequities have on the BVI community, the ways screen reader users sought access to data-driven information and made use of online visualizations to form insights, and the pressing need to make larger strides towards improving data literacy, building confidence, and enriching methods of access. Based on our findings, we provide recommendations for researchers and practitioners to broaden data accessibility on the web.

The high voltage (5 V class) Li-ion batteries with spinel LiNi0.5Mn1.5O4 (LNMO), olivine LiCoPO4, or layer–layer composite xLi2MnO3·(1 – x)­LiMnO2 as a cathode and carbon (e.g., graphite) as an anode are expected to become a new generation of high energy density batteries. However, the cycle stability of these batteries is very poor because a stable cathode–electrolyte interface (CEI) layer cannot be formed in a commercial carbonate electrolyte at such a high voltage, and then the electrolyte oxidation products from the cathode cause the anodes to fail. In this work, taking LNMO/graphite full cell as the representative, the effect of Li metal and lithiated LNMO interlayers on the cycling behavior of the cell is studied. It is found that both interlayers can greatly improve the cycle life of the full cell, because they can consume and block the electrolyte oxidation products from the LNMO cathode, thus protecting the graphite anode from being destroyed. The optimum reduction activity range of a lithiated interlayer is 0.75–2.0 V (vs Li+/Li) for the 5 V class Li-ion batteries because the interlayer with excessive reductivity (<0.75 V) can reduce and decompose the electrolyte itself.

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