Pressure tuning of optical reflectivity in LuH2

Recently, the claim of room-temperature superconductivity in nitrogen-doped lutetium hydride at near-ambient conditions has attracted tremendous attention. Criticism of the work rises shortly, while further explorations are needed to settle the dispute. One of the intriguing observations is the pressured-induced color change, which has been reproduced in the lutetium dihydride LuH2 while its mechanism remains unclear. Through optical reflectivity measurements of LuH2 in the visible to near-infrared region, we observe strong light absorption next to the sharp plasmon resonance, which continuously shifts to higher energies with increasing pressure. It gives rise to the increased reflection of red light and suppressed reflection of blue light. Our work sheds light on resolving the puzzles regarding the pressure induced color change in LuH2.Comment: 8 pages, 6 figure

Deciphering the spatiotemporal trade-offs and synergies between ecosystem services and their socio-ecological drivers in the plain river network area

Understanding changes in ecosystem services (ESs) and quantitatively identifying the drivers that influence these changes are essential for achieving sustainable ecosystem development. In this study, multiple data sources and techniques, including meteorological data, land use/cover data, soil data, the InVEST model, and ArcGIS, were used to analyze the spatiotemporal variation characteristics of carbon storage, habitat quality, soil retention, water yield, and crop product supply in Xinghua City from 2000 to 2015. Additionally, we explored the causes of these changes and the interrelationships among these ESs. The results showed that: (1) During the study period, carbon storage and habitat quality declined, water yield fluctuated and increased, and soil retention had small interannual variations. The supply capacity of crop products first increased rapidly and then stabilized. (2) ESs were influenced by multiple drivers, with altitude having the strongest explanatory power for habitat quality and soil retention, and food production having the strongest explanatory power for crop product supply. (3) Relationships between different ESs were variable and changed over time. This study could enrich the understanding of spatial and temporal changes and drivers of ESs in the plain river network area, which has important implications for future land use planning and sustainable development of ESs

Analysis of an Alanine/Arginine Mixture by Using TLC/FTIR Technique

We applied TLC/FTIR coupled with mapping technique to analyze an alanine/arginine mixture. Narrow band TLC plates prepared by using AgI as a stationary phase were used to separate alanine and arginine. The distribution of alanine and arginine spots was manifested by a 3D chromatogram. Alanine and arginine can be successfully separated by the narrow band TLC plate. In addition, the FTIR spectra of the separated alanine and arginine spots on the narrow band TLC plate are roughly the same as the corresponding reference IR spectra

Passing Stages Division of the Pedestrians and Bicycles Conglomeration at Signalized Intersection of Chinese City

This paper mainly studies how to divide the passing stages of the pedestrians and bicycles conglomeration at signalized intersection in Chinese urban area. The conception of pedestrians and bicycles conglomeration is defined after analyzing the two-stage characteristics of pedestrians and bicycles groups. Seven intersections were chosen in Beijing as examples. After video analysis, the real-time displacement and the real-time velocities of seven intersections in one signal cycle are extracted. It is found that the procedure of pedestrians and bicycles passing the intersection can be divided into two stages, which shows distinct characteristics. Video records taken from the observational survey are used to extract the real displacement of pedestrians and bicycles and the passing behaviors images. A new approach is presented to calculate the occupation ratio of the pedestrians and bicycles conglomeration, based on the “suppositional grids” division of the effective crosswalks. Finally, the grey relational analysis is applied to divide the mixed groups’ passing stages based on the occupation ratio of conglomeration. A signalized intersection in Beijing is presented as a case study, and the passing stages are clustered into four stages from initial five stages and the results indicate that the trend of change in different stages is obvious

GM-PHD Filter Combined with Track-Estimate Association and Numerical Interpolation

For the standard Gaussian mixture probability hypothesis density (GM-PHD) filter, the number of targets can be overestimated if the clutter rate is too high or underestimated if the detection rate is too low. These problems seriously affect the accuracy of multitarget tracking for the number and the value of measurements and clutters cannot be distinguished and recognized. Therefore, we proposed an improved GM-PHD filter to tackle these problems. Firstly, a track-estimate association was implemented in the filtering process to detect and remove false-alarm targets. Secondly, a numerical interpolation technique was used to compensate the missing targets caused by low detection rate. At the end of this paper, simulation results were presented to demonstrate the proposed GM-PHD algorithm is more effective in estimating the number and state of targets than the previous ones

Restorative Effects of Pocket Parks on Mental Fatigue among Young Adults: A Comparative Experimental Study of Three Park Types

Urban parks have been proven to effectively reduce mental fatigue among city residents; however, there has been less focus on the mental health benefits offered by pocket parks in densely populated areas from a field experiment perspective. Additionally, there is insufficient evidence providing information on the environmental characteristics that support recovery from mental fatigue. This study was based on 80 young adults aged 19–25 years. Three types of pocket parks were selected: street corners, interblock spaces, and intrablock spaces. Through a field experiment with questionnaire collection, physiological (BP, HR, and LF/HF) and psychological indicators (FS-14 and VAS) were used to explore the relationship between various pocket park features and respondents’ mental fatigue recovery. This study investigated the restorative effects of 10 environmental features by collecting questionnaires. The results suggested that different types of pocket parks have the recovery effect of pocket parks. Four environmental factors, namely, vegetation colour (β = −0.472, p = 0.002), vegetation coverage (β = 0.298, p = 0.046), resting facility comfort (β = −0.336, p = 0.028), and plant species (β = −0.437, p = 0.003), were more predictive of mental fatigue recoverability. However, factors such as neighbourhood hygiene and spatial privacy did not show significant predictive effects. Our findings provide robust evidence for urban park planning and design. In the future landscape design of high-density urban areas, greater emphasis can be placed on the construction of pocket parks. The rational selection and configuration of environmental factors that contribute to recovery effects in pocket parks will contribute to meeting the psychological health service needs of high-density urban populations