scholarly journals Advances in Two-Dimensional MXenes for Nitrogen Electrocatalytic Reduction to Ammonia

2020 ◽  
Vol 2020 ◽  
pp. 1-11 ◽  
Author(s):  
Lan-lan Yu ◽  
Jiang-zhou Qin ◽  
Wen-jun Zhao ◽  
Zhi-guang Zhang ◽  
Jun Ke ◽  
...  
Keyword(s):  
High Energy ◽  
Raw Material ◽  
Synthesis Methods ◽  
Two Dimensional ◽  
Catalytic Material ◽  
Temperature And Pressure ◽  
Negative Impacts ◽  
High Energy Consumption ◽  
Insight Into ◽  
Shed Light

As an important chemical raw material, ammonia is mainly produced by the traditional Haber-Bosch process, which has certain limitations such as high energy consumption, high safety responsibility, and severe pollution, thereby having negative impacts on ecosystem. The synthesis of ammonia from dinitrogen at ambient temperature and pressure is one of the most attractive topics in the field of chemistry. As a new two-dimensional nanomaterial, MXene has excellent electrochemical properties and is a potential catalytic material for electrocatalytic nitrogen fixation. In this review, we firstly introduce the crystal, electronic structures of two-dimensional MXenes and summarize the synthesis methods, N2 reduction, and simulation computation, as well as have insight into the challenges of MXenes, which shed light on the development of highly efficient MXene-based electrocatalysts in the reduction of N2 to ammonia.

Unpacking Subjective Creativity Ratings: Using Embeddings to Explain and Measure Idea Novelty

2018 ◽  
Author(s):  
Faez Ahmed ◽  
Mark Fuge ◽  
Sam Hunter ◽  
Scarlett Miller
Keyword(s):  
Computational Methods ◽  
Ground Truth ◽  
Two Dimensional ◽  
Human Judgment ◽  
Design Idea ◽  
Design Ideas ◽  
Mental Connections ◽  
Insight Into ◽  
Inherent Part ◽  
Shed Light

Assessing similarity between design ideas is an inherent part of many design evaluations to measure novelty. In such evaluation tasks, humans excel at making mental connections among diverse knowledge sets and scoring ideas on their uniqueness. However, their decisions on novelty are often subjective and difficult to explain. In this paper, we demonstrate a way to uncover human judgment of design idea similarity using two dimensional idea maps. We derive these maps by asking humans for simple similarity comparisons of the form “Is idea A more similar to idea B or to idea C?” We show that these maps give insight into the relationships between ideas and help understand the domain. We also propose that the novelty of ideas can be estimated by measuring how far items are on these maps. We demonstrate our methodology through the experimental evaluations on two datasets of colored polygons (known answer) and milk frothers (unknown answer) sketches. We show that these maps shed light on factors considered by raters in judging idea similarity. We also show how maps change when less data is available or false/noisy ratings are provided. This method provides a new direction of research into deriving ground truth novelty metrics by combining human judgments and computational methods.

Selective Recovery of Precious Metals through Photocatalysis

2020 ◽  
Author(s):  
Yao Chen ◽  
Mengjiao Xu ◽  
Jieya Wen ◽  
Yu Wan ◽  
Qingfei Zhao ◽  
...  
Keyword(s):  
Large Scale ◽  
Precious Metals ◽  
Strong Acid ◽  
High Energy ◽  
Circuit Boards ◽  
Strong Base ◽  
Whole Process ◽  
Temperature And Pressure ◽  
Dissolution Efficiency ◽  
High Energy Consumption

Abstract Precious metals such as gold and platinum are valued materials for a variety of important applications, but their scarcity poses a risk of supply interruption. However, the dissolution and recovery of precious metals using the current methods are limited by associated serious environmental pollution and high energy consumption. Here, we show a photocatalytic process that allows one to selective retrieve 7 kinds of precious metal elements (Ag, Au, Pd, Pt, Ru, Rh and Ir) (with dissolution efficiency of 99%) from waste circuit boards, ternary automotive catalysts and even ores. Precious metals is recovered with high purity (≥98%) through a simple reductive method. The whole process only needs light and catalyst without strong acid, strong base and highly toxic cyanide. It has an environmentally friendly, scalable and efficient way, in which the catalyst has been recycled more than 100 times under normal temperature and pressure without performance degradation. It has successfully realized the scale of dissolution from grams to kilograms, and it is expected to realize large-scale recovery of precious metals in industrial application. This general approach provides an unprecedent technology for recycling resources on earth.

scholarly journals 1,000,000 Giant Pulses from the Crab Pulsar

2017 ◽  
Vol 13 (S337) ◽  
pp. 380-381
Author(s):  
Mitchell B. Mickaliger ◽  
Ben W. Stappers ◽  
Cees G. Bassa ◽  
Aldus G. Fletcher
Keyword(s):  
Single Pulse ◽  
High Energy ◽  
Daily Basis ◽  
Large Set ◽  
Crab Pulsar ◽  
Energy Distributions ◽  
Giant Pulses ◽  
High Energy Tail ◽  
Insight Into ◽  
Shed Light

AbstractThe Crab pulsar was first detected soon after the discovery of pulsars, and has long been studied for its unique traits. One of these traits, giant pulses that can be upwards of 1000 times brighter than the average pulse, was key to the Crab’s initial detection. Giant pulses are only seen in a few pulsars, and their energy distributions distinguish them from normal pulsed emission. There have been many studies over a period of decades to measure the power-law slope of these energy distributions, which provide insight into the possible emission mechanism of these giant pulses.The 42-foot telescope at Jodrell Bank Observatory monitors the Crab pulsar on a daily basis. We have single-pulse data dating back to 2012, containing roughly 1,000,000 giant pulses, the largest sample of Crab giant pulses to date. This large set of giant pulses allows us to do a range of science, including pulse-width studies and in-depth studies of giant-pulse energy distributions. The latter are particularly interesting, as close inspection of the high-energy tail of the energy distribution allows us to investigate the detectability of extragalactic giant-pulsing pulsars. Also, by calculating rates from these energy distributions, we may be able to shed light on a possible link between Fast Radio Bursts and giant pulses.

Explore Impacts of Urban Compactness on Energy Consumption

2012 ◽  
Vol 260-261 ◽  
pp. 46-49
Author(s):  
Hsueh Sheng Chang ◽  
Tzu Ling Chen ◽  
Chi Fei Wang
Keyword(s):  
Energy Consumption ◽  
Global Climate ◽  
Environmental Issues ◽  
High Energy ◽  
Anthropogenic Emission ◽  
Compact City ◽  
Mixed Land Use ◽  
Negative Impacts ◽  
High Energy Consumption ◽  
Emission Of Greenhouse Gases

Anthropogenic emission of greenhouse gases (GHGs) result in global climate destabilization, and the elements of GHGs associated with climate change are now well understood and a link to urban GHGs emissions has been well articulated. Compact city concept has been proposed for a while to response high energy consumption and GHGs emission in urban area. However, over compact might come up some problems, such as over-crowded of population, buildings, and cars which brining up other environmental issues. This study attempts to investigate potential negative impacts of urban compactness on energy consumption. The result shows that under a threshold of high density and mixed land use, it might come up energy saving outcome. However, it will become energy consumption while exceeding the threshold.

scholarly journals The Issues of Residential House Systems and How to Make It More Sustainable Systems

2020 ◽  
Vol 9 (2) ◽  
pp. 232
Author(s):  
Ahmad R. Ahmad
Keyword(s):  
Renewable Resources ◽  
Carbon Dioxide Emissions ◽  
High Water ◽  
High Energy ◽  
Waste Generation ◽  
Sustainable Systems ◽  
Residential House ◽  
Negative Impacts ◽  
High Energy Consumption ◽  
Inputs And Outputs

This paper highlighted a set of issues facing the residential house system and makes it unsustainable systems including: high energy consumption, high water demand, waste generation, and carbon dioxide emissions. The boundaries, inputs and outputs of residential house systems are displayed in detail and illustrated by modeling these systems for the purpose of understanding the relationships and interactions between these inputs and outputs and components of these systems. Thus, presenting a range of strategies that can be implemented to make residential house systems more sustainable and reduce the negative impacts of these systems on the environment and other sources such as water, energy and non-renewable resources to a minimum level.

Parabolas from Reconstructed Surfaces Observed in Convergent-Beam RHEED Patterns

1990 ◽  
Vol 48 (2) ◽  
pp. 398-399
Author(s):  
M. Gajdardziska-Josifovska
Keyword(s):  
Electron Microscopy ◽  
High Energy ◽  
Two Dimensional ◽  
High Energy Electron ◽  
Reflection And Transmission ◽  
Experimental Diffraction Pattern ◽  
Surface Resonance ◽  
Reconstructed Surfaces ◽  
Reflection Electron Microscopy ◽  
Convergent Beam

Parabolas have been observed in the reflection high-energy electron diffraction (RHEED) patterns from surfaces of single crystals since the early thirties. In the last decade there has been a revival of attempts to elucidate the origin of these surface parabolas. The renewed interest stems from the need to understand the connection between the parabolas and the surface resonance (channeling) condition, the latter being routinely used to obtain higher intensity in reflection electron microscopy (REM) images of surfaces. Several rather diverging descriptions have been proposed to explain the parabolas in the reflection and transmission Kikuchi patterns. Recently we have developed an unifying general treatment in which the parabolas are shown to be K-lines of two-dimensional lattices. Here we want to review the main features of this description and present an experimental diffraction pattern from a 30° MgO (111) surface which displays parabolas that can be attributed to the surface reconstruction.

Sentence-Based Experience Logging in New Hearing Aid Users

2020 ◽  
Vol 29 (3S) ◽  
pp. 631-637
Author(s):  
Katja Lund ◽  
Rodrigo Ordoñez ◽  
Jens Bo Nielsen ◽  
Dorte Hammershøi
Keyword(s):  
Hearing Aid ◽  
Patient Experiences ◽  
Online Tool ◽  
Rehabilitation Process ◽  
Hearing Rehabilitation ◽  
Clinical Observations ◽  
Hearing Aid Use ◽  
Wide Range ◽  
Insight Into ◽  
Shed Light

Purpose The aim of this study was to develop a tool to gain insight into the daily experiences of new hearing aid users and to shed light on aspects of aided performance that may not be unveiled through standard questionnaires. Method The tool is developed based on clinical observations, patient experiences, expert involvement, and existing validated hearing rehabilitation questionnaires. Results An online tool for collecting data related to hearing aid use was developed. The tool is based on 453 prefabricated sentences representing experiences within 13 categories related to hearing aid use. Conclusions The tool has the potential to reflect a wide range of individual experiences with hearing aid use, including auditory and nonauditory aspects. These experiences may hold important knowledge for both the patient and the professional in the hearing rehabilitation process.

Aleksey Peshkov as an editor of Samarskaya Gazeta

2020 ◽  
pp. 128-138
Author(s):  
A. S. Bik-Bulatov
Keyword(s):  
Local History ◽  
Organizational Skills ◽  
First Time ◽  
New Evidence ◽  
Insight Into ◽  
Shed Light

The article uses little known letters of M. Gorky, many of which were published for the first time in 1997, as well as findings of Samara-based experts in local history to shed light on the writer’s work as editor-in-chief of the Samarskaya Gazeta newspaper in 1895. The researcher introduces hitherto unstudied reminiscences of the journalist D. Linyov (Dalin) about this period, which reference a letter by Gorky, now lost. The paper details a newly discovered episode of Gorky’s professional biography as a journalist: it concerns his campaign against a Samara ‘she-wolf,’ the madam of a local brothel A. Neucheva. Linyov’s reminiscences turn out to be an important and interesting source, offering an insight into the daily grind of the young editor Gorky, providing new evidence of his excellent organizational skills, and describing his moral and social stance. The author presents his work in the context of a recently initiated broader discussion about the need to map out all Russian periodicals for the period until 1917, as well as all research devoted to individual publications.

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