Analysis of landscape influencing factors of urban waterfront greenways based on the scenic beauty estimation method, taking Tongjian Lake in Hangzhou as an example

In order to assess the unique beauty of Tongjian Lake in Hangzhou, 80 sample photographs were selected for landscape beauty degree assessment using the Scenic Beauty Estimation method. The 14 characteristic influencing factors of landscape photos were extracted according to the Scenic Beauty Estimation value, and the influencing factors with insignificant differences and small bias correlation coefficients were eliminated through multiple linear regression analysis. The results showed that the main factors affecting the expression of the beauty of Tongjian Lake were water ecology, greenway morphology, landscape openness, water area ratio, vegetation color richness, and vignette matching. Combining the abovementioned analysis results, the two-dimensional plan, isometric map, and three-dimensional space are combined to show the main factors in a visual way, and on this basis, the corresponding optimization strategy is proposed. It provides a reference for future urban waterfront greenway landscape creation

Defect-enriched iron fluoride-oxide nanoporous thin films bifunctional catalyst for water splitting

Developing cost-effective electrocatalysts operated in the same electrolyte for water splitting, including oxygen and hydrogen evolution reactions, is important for clean energy technology and devices. Defects in electrocatalysts strongly influence their chemical properties and electronic structures, and can dramatically improve electrocatalytic performance. However, the development of defect-activated electrocatalyst with an efficient and stable water electrolysis activity in alkaline medium remains a challenge, and the understanding of catalytic origin is still limited. Here, we highlight defect-enriched bifunctional eletrocatalyst, namely, three-dimensional iron fluoride-oxide nanoporous films, fabricated by anodization/fluorination process. The heterogeneous films with high electrical conductivity possess embedded disorder phases in crystalline lattices, and contain numerous scattered defects, including interphase boundaries, stacking faults, oxygen vacancies, and dislocations on the surfaces/interface. The heterocatalysts efficiently catalyze water splitting in basic electrolyte with remarkable stability. Experimental studies and first-principle calculations suggest that the surface/edge defects contribute significantly to their high performance

Automated Mapping of Ms 7.0 Jiuzhaigou Earthquake (China) Post-Disaster Landslides Based on High-Resolution UAV Imagery

The Ms 7.0 Jiuzhaigou earthquake that occurred on 8 August 2017 triggered hundreds of landslides in the Jiuzhaigou valley scenic and historic-interest area in Sichuan, China, causing heavy casualties and serious property losses. Quick and accurate mapping of post-disaster landslide distribution is of paramount importance for earthquake emergency rescue and the analysis of post-seismic landslides distribution characteristics. The automatic identification of landslides is mostly based on medium- and low-resolution satellite-borne optical remote-sensing imageries, and the high-accuracy interpretation of earthquake-triggered landslides still relies on time-consuming manual interpretation. This paper describes a methodology based on the use of 1 m high-resolution unmanned aerial vehicle (UAV) imagery acquired after the earthquake, and proposes a support vector machine (SVM) classification method combining the roads and villages mask from pre-seismic remote sensing imagery to accurately and automatically map the landslide inventory. Compared with the results of manual visual interpretation, the automatic recognition accuracy could reach 99.89%, and the Kappa coefficient was higher than 0.9, suggesting that the proposed method and 1 m high-resolution UAV imagery greatly improved the mapping accuracy of the landslide area. We also analyzed the spatial-distribution characteristics of earthquake-triggered landslides with the influenced factors of altitude, slope gradient, slope aspect, and the nearest faults, which provided important support for the further study of post-disaster landslide distribution characteristics, susceptibility prediction, and risk assessment.This work was funded by the National Key Research and Development Program of China (Project No. 2018YFC1505202), the National Natural Science Foundation of China (41941019), the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Independent Research Project (SKLGP2020Z012), the project on identification and monitoring of potential geological hazards with remote sensing in Sichuan Province (510201202076888) and the Everest Scientific Project at Chengdu University of Technology (2020ZF114103)

Post-disaster assessment of 2017 catastrophic Xinmo landslide (China) by spaceborne SAR interferometry

Timely and effective post-disaster assessment is of significance for the design of rescue plan, taking disaster mitigation measures and disaster analysis. Field investigation and remote sensing methods are the common ways to perform post-disaster assessment, which are usually limited by dense cloud coverage, potential risk, and tough transportation etc. in the mountainous area. In this paper, we employ the 2017 catastrophic Xinmo landslide (Sichuan, China) to demonstrate the feasibility of using spaceborne synthetic aperture radar (SAR) data to perform timely and effective post-disaster assessment. With C-band Sentinel-1 data, we propose to combine interferometric coherence to recognize the stable area, which helps us successfully identify landslide source area and boundaries in a space-based remote sensing way. Complementarily, X-band TanDEM-X SAR data allow us to generate a precise pre-failure high-resolution digital elevation model (DEM), which provides us the ability to accurately estimate the depletion volume and accumulation volume of Xinmo landslide. The results prove that spaceborne SAR can provide a quick, valuable, and unique assistance for post-disaster assessment of landslides from a space remote sensing way. At some conditions (bad weather, clouds, etc.), it can provide reliable alternative.This work was funded by Sichuan Science and Technology Plan Key Research and Development Program (Grant No. 2018SZ0339), National Natural Science Foundation of China (Grant No. 41801391), State Key Laboratory of Geodesy and Earth’s Dynamics Open fund (Grant No. SKLGED2018-5-3-E), The Funds for Creative Research Groups of China (Grant No. 41521002) and partially supported by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO), the State Agency of Research (AEI), and European Funds for Regional Development (FEDER), under project TIN2014-55413-C2-2-P and by the Spanish Ministry of Education, Culture and Sport, under project PRX17/00439. This work was also supported by the National Environment Research Council (NERC) through the Centre for the Observation and Modeling of Earthquakes, Volcanoes and Tectonics (COMET, ref.: come30001), the LiCS project (ref. NE/K010794/1), the ESA-MOST DRAGON-4 project (ref. 32244), and the Hunan Province Key Laboratory of Coal Resources Clean-Utilization and Mine Environment Protection, Hunan University of Science and Technology (Ref. E21608)

Hydrogen Diffusion and Stabilization in Single-crystal VO2 Micro/nanobeams by Direct Atomic Hydrogenation

We report measurements of the diffusion of atomic hydrogen in single crystalline VO2 micro/nanobeams by direct exposure to atomic hydrogen, without catalyst. The atomic hydrogen is generated by a hot filament, and the doping process takes place at moderate temperature (373 K). Undoped VO2 has a metal-to-insulator phase transition at ~340 K between a high-temperature, rutile, metallic phase and a low-temperature, monoclinic, insulating phase with a resistance exhibiting a semiconductor-like temperature dependence. Atomic hydrogenation results in stabilization of the metallic phase of VO2 micro/nanobeams down to 2 K, the lowest point we could reach in our measurement setup. Based on observing the movement of the hydrogen diffusion front in single crystalline VO2 beams, we estimate the diffusion constant for hydrogen along the c-axis of the rutile phase to be 6.7 x 10^{-10} cm^2/s at approximately 373 K, exceeding the value in isostructural TiO2 by ~ 38x. Moreover, we find that the diffusion constant along the c-axis of the rutile phase exceeds that along the equivalent a-axis of the monoclinic phase by at least three orders of magnitude. This remarkable change in kinetics must originate from the distortion of the "channels" when the unit cell doubles along this direction upon cooling into the monoclinic structure. Ab initio calculation results are in good agreement with the experimental trends in the relative kinetics of the two phases. This raises the possibility of a switchable membrane for hydrogen transport.Comment: 23 pages, 4 figs + supporting materia

Dihydromyricetin Attenuates Streptozotocin-induced Liver Injury and Inflammation in Rats via Regulation of NF-κB and AMPK Signaling Pathway

open access articleDihydromyricetin (DHM) dramatically improved the quality of life for Streptozotocin (STZ)-induced diabetic rats and significantly increased the activity of antioxidant enzymes in the liver. Moreover, DHM successfully ameliorated diabetes-induced liver damage by suppression of apoptosis in the liver, as indicated by the decreased levels of Bax and cleaved caspase-3. In diabetic rats, the levels of tumor necrosis factor-α and interleukin-1β in the liver were significantly increased. However, the administration of DHM (100–400 mg/kg/day) for 6 weeks restored the cytokine levels to their normal values in a dose-dependent manner in diabetic rats by the regulation of nuclear factor-kappa B signaling pathway. In addition, DHM significantly induced 5' AMP-activated protein kinase (AMPK) phosphorylation and decreased MyD88, TLR4, p38, GSK-3β protein expression levels in the liver of diabetic rats. In conclusion, DHM could improve STZ-induced liver impairment by preventing oxidative stress, apoptosis, and inflammation

Atomic H-Induced Mo_2C Hybrid as an Active and Stable Bifunctional Electrocatalyst

Mo_2C nanocrystals (NCs) anchored on vertically aligned graphene nanoribbons (VA-GNR) as hybrid nanocatalysts (Mo_2C-GNR) are synthesized through the direct carbonization of metallic Mo with atomic H treatment. The growth mechanism of Mo2C NCs with atomic H treatment is discussed. The Mo_2C-GNR hybrid exhibits highly active and durable electrocatalytic performance for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). For HER, in an acidic solution the Mo_2C-GNR has an onset potential of 39 mV and a Tafel slope of 65 mV dec^(-1), in a basic solution Mo_2C-GNR has an onset potential of 53 mV, and Tafel slope of 54 mV dec^(-1). It is stable in both acidic and basic media. Mo2C-GNR is a high activity ORR catalyst with a high peak current density of 2.01 mA cm^(-2), an onset potential of 0.94 V that is more positive vs reversible hydrogen electrode, a high electron transfer number n (∼3.86) and long-term stability

Defect-enriched iron fluoride-oxide nanoporous thin films bifunctional catalyst for water splitting

Developing cost-effective electrocatalysts operated in the same electrolyte for water splitting, including oxygen and hydrogen evolution reactions, is important for clean energy technology and devices. Defects in electrocatalysts strongly influence their chemical properties and electronic structures, and can dramatically improve electrocatalytic performance. However, the development of defect-activated electrocatalyst with an efficient and stable water electrolysis activity in alkaline medium remains a challenge, and the understanding of catalytic origin is still limited. Here, we highlight defect-enriched bifunctional eletrocatalyst, namely, three-dimensional iron fluoride-oxide nanoporous films, fabricated by anodization/fluorination process. The heterogeneous films with high electrical conductivity possess embedded disorder phases in crystalline lattices, and contain numerous scattered defects, including interphase boundaries, stacking faults, oxygen vacancies, and dislocations on the surfaces/interface. The heterocatalysts efficiently catalyze water splitting in basic electrolyte with remarkable stability. Experimental studies and first-principle calculations suggest that the surface/edge defects contribute significantly to their high performance

Atomic H-Induced Mo_2C Hybrid as an Active and Stable Bifunctional Electrocatalyst

Mo_2C nanocrystals (NCs) anchored on vertically aligned graphene nanoribbons (VA-GNR) as hybrid nanocatalysts (Mo_2C-GNR) are synthesized through the direct carbonization of metallic Mo with atomic H treatment. The growth mechanism of Mo2C NCs with atomic H treatment is discussed. The Mo_2C-GNR hybrid exhibits highly active and durable electrocatalytic performance for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). For HER, in an acidic solution the Mo_2C-GNR has an onset potential of 39 mV and a Tafel slope of 65 mV dec^(-1), in a basic solution Mo_2C-GNR has an onset potential of 53 mV, and Tafel slope of 54 mV dec^(-1). It is stable in both acidic and basic media. Mo2C-GNR is a high activity ORR catalyst with a high peak current density of 2.01 mA cm^(-2), an onset potential of 0.94 V that is more positive vs reversible hydrogen electrode, a high electron transfer number n (∼3.86) and long-term stability