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Articles 55471 - 55500 of 197562

Full-Text Articles in Engineering

High Wind Alerts: A System Created With Observations From The X-Band Teaching And Research Radar, Lauren Warner Aug 2020

High Wind Alerts: A System Created With Observations From The X-Band Teaching And Research Radar, Lauren Warner

The Journal of Purdue Undergraduate Research

Following the August 13, 2011, Indiana State Fair stage collapse tragedy, caused by a wind gust from an approaching thunderstorm, Purdue University enforced a wind speed restriction of 30 mph (13 m s-1) for tents at outdoor events. During these events, volunteers stand outside with handheld anemometers, measuring and reporting when the wind speeds exceed this limit. In this study, we report testing of a new system to automate high-wind alerts based on observations from a Doppler radar, the X-band Teaching and Research Radar (XTRRA), near Purdue’s campus. XTRRA scans over campus at low elevations approximately every 5 minutes. Using …


Human Factors Analysis And Classification System (Hfacs): As Applied To Asiana Airlines Flight 214, Alex Small Aug 2020

Human Factors Analysis And Classification System (Hfacs): As Applied To Asiana Airlines Flight 214, Alex Small

The Journal of Purdue Undergraduate Research

The Human Factors Analysis and Classification System (HFACS) is a safety tool that aids in the identification and analysis of organizational factors that contribute to aircraft accidents. By using the HFACS model, safety investigators can better understand the existing conditions that contribute to accidents, which then allows for the development and implementation of safety programs to prevent these conditions. In this study, the HFACS framework was utilized to identify the human factors that contributed to the Asiana Airlines flight 214 accident that occurred on July 6, 2013. The results of this study indicate that inadequate pilot training, lack of upper-level …


Comparison Of Machine Learning Models: Gesture Recognition Using A Multimodal Wrist Orthosis For Tetraplegics, Charlie Martin Aug 2020

Comparison Of Machine Learning Models: Gesture Recognition Using A Multimodal Wrist Orthosis For Tetraplegics, Charlie Martin

The Journal of Purdue Undergraduate Research

Many tetraplegics must wear wrist braces to support paralyzed wrists and hands. However, current wrist orthoses have limited functionality to assist a person’s ability to perform typical activities of daily living other than a small pocket to hold utensils. To enhance the functionality of wrist orthoses, gesture recognition technology can be applied to control mechatronic tools attached to a novel fabricated wrist brace. Gesture recognition is a growing technology for providing touchless human-computer interaction that can be particularly useful for tetraplegics with limited upper-extremity mobility. In this study, three gesture recognition models were compared—two dynamic time-warping models and a hidden …


Navigating In Numerous Video Data: User Interface Design For An On-Camera Video Analytics Engine, Sabriya Maryam Alam Aug 2020

Navigating In Numerous Video Data: User Interface Design For An On-Camera Video Analytics Engine, Sabriya Maryam Alam

The Journal of Purdue Undergraduate Research

Video analytics powered by artificial intelligence shows high promise in making our society smarter. Harnessing large amounts of video data, however, requires the development of processing systems demonstrating high performance and high efficiency. To this end, this work has contributed to a video analytics system powered by artificial intelligence for object detection and recognition. Rather than streaming all the video frames to the cloud, the system analyzes images on-camera and only returns those of interest to the cloud. This edge analytics research-grade software is available, but it lacks a simple web interface for general use by scientists, engineers, and other …


Long-Run Traffic Simulations For Multi-Lane Road Bridges, Róisín Donnelly, Lorcan Connolly, Ilaria Bernardini Aug 2020

Long-Run Traffic Simulations For Multi-Lane Road Bridges, Róisín Donnelly, Lorcan Connolly, Ilaria Bernardini

Civil Engineering Research in Ireland 2020

The maintenance and repair of ageing bridges is a concern for road infrastructure managers. This issue is amplified by the increasing weights and frequency of travel of freight vehicles in recent times. In order to accurately assess the risk of damage for road bridges, it is essential to have knowledge of both historical and current bridge loading. When available, site-specific Weigh-in-Motion (WIM) data can be effective in creating representative load models for a structure. However, for cases where WIM data is not available and in cases where future damage must be predicted, it is necessary to simulate appropriate data using …


Repair & Rehabilitation Of Daly's (Shakey) Bridge, Cork City, Michael Minehane, John Gamble Aug 2020

Repair & Rehabilitation Of Daly's (Shakey) Bridge, Cork City, Michael Minehane, John Gamble

Civil Engineering Research in Ireland 2020

This paper describes the rehabilitation of (Shakey) Bridge, an existing single-span suspension bridge crossing the northern channel of the River Lee in Cork City. The bridge was opened in 1927 to replace an earlier ferry crossing at the same location. Daly’s bridge is included on the Record of Protected Structures and the National Inventory of Architectural Heritage. It remains the only suspension bridge in Cork City and is the only surviving bridge of its kind in Ireland. It is considered to be a significant contributor to the architectural heritage of the city. This case study describes the project development including …


Reinforcement Of Timber Elements In Compression Perpendicular To The Grain Using Compressed Wood Dowels, Michael Conway, Conan O'Ceallaigh, Sameer Mehra, Annette M. Harte Aug 2020

Reinforcement Of Timber Elements In Compression Perpendicular To The Grain Using Compressed Wood Dowels, Michael Conway, Conan O'Ceallaigh, Sameer Mehra, Annette M. Harte

Civil Engineering Research in Ireland 2020

In the past decade, there has been an increased focus on the environmental impacts of construction and a movement towards more sustainable construction products. Timber is one such sustainable product that can achieve these environmental targets but, while timber has a high strength-to-weight ratio parallel to the grain, it demonstrates poor strength perpendicular to the grain. As a result, stress perpendicular to the grain is an important factor in the design of timber structures, especially in areas of concentrated loading, such as supports. This paper describes a study, which examines the use of compressed wood dowels as a sustainable alternative …


Development And Testing Of A Deployable Double Layer Tensegrity Grid, Michael Quilligan, Valentin Gomez-Jauregui, Cristina Manchado, Cesar Otero Aug 2020

Development And Testing Of A Deployable Double Layer Tensegrity Grid, Michael Quilligan, Valentin Gomez-Jauregui, Cristina Manchado, Cesar Otero

Civil Engineering Research in Ireland 2020

Tensegrity is a structural principle based on the use of isolated or contiguous pin jointed components in compression inside a net of continuous tension. Although the concept has been studied for many decades, relatively few examples of tensegrity structures have been used for civil engineering purposes.


A Review Of The Engineering Constraints And Project Management Challenges Involved In Utilising Scot’S Church As A Heritage Asset Through Responsible Adaptive Reuse And Conservation Strategies, Óisín Smith Aug 2020

A Review Of The Engineering Constraints And Project Management Challenges Involved In Utilising Scot’S Church As A Heritage Asset Through Responsible Adaptive Reuse And Conservation Strategies, Óisín Smith

Civil Engineering Research in Ireland 2020

In the field of structural building, there has been a rising popularity in adaptive reuse of older structures, which stems from a variety of stimuli. Apart from preserving built heritage, providing old buildings with new functions promotes sustainability while preventing and containing urban sprawl. Target 11.4 of the United Nation’s Sustainable Development Goals Agenda 2030 explicitly outlines that “more efforts to protect and safeguard the world’s cultural and natural heritage” are required. In order to valorise and regenerate obsolescent structures, intervention is often required. The dissertation provides a comprehensive overview of conservation engineering and demonstrates the importance of an engineer’s …


An Evaluation Of Design Issues Identified During Reviews Of Structural Designs Of Buildings From 2015 To 2020, Patrick Crean, Richard Osborne Aug 2020

An Evaluation Of Design Issues Identified During Reviews Of Structural Designs Of Buildings From 2015 To 2020, Patrick Crean, Richard Osborne

Civil Engineering Research in Ireland 2020

A recent study on failures of structures in Ireland indicated that approximately 40% could be apportioned to designer error. A 2019 report into recent structural cracking of a high-rise building in Sydney Australia recommended that Independent third party checking by a Chartered Engineer should be a requirement on all major projects prior to construction. The report also stated that the critical elements of the design on these projects should be identified. It is obvious that a certain percentage of buildings constructed each year contain design flaws and only a small proportion of these ever result in a failure. However there …


Loading On Long Span Bridges In Heavily Trafficked Areas, Michael Quilligan, Eugene O'Brien Aug 2020

Loading On Long Span Bridges In Heavily Trafficked Areas, Michael Quilligan, Eugene O'Brien

Civil Engineering Research in Ireland 2020

The critical traffic loading condition for long-span bridges is congestion when vehicles may be closely spaced together. Data on very high traffic flows is limited however, as induction loops which are typically used to collect traffic data, are ineffective when traffic flow breaks down. A number of long span bridges are located in areas of high traffic with periods of recurring congestion occurring daily. While the inter-vehicle gap distances are greater than those occurring during non-recurring full stop accident type events, the high frequency of the recurring congestion events can increase the probability of a critical load case occurring.


A Numerical Study Of The Effect Of Wind Barriers On Traffic And The Bridge Deck, Yuxiang Zhang, Philip Cardiff, Jennifer Keenahan Aug 2020

A Numerical Study Of The Effect Of Wind Barriers On Traffic And The Bridge Deck, Yuxiang Zhang, Philip Cardiff, Jennifer Keenahan

Civil Engineering Research in Ireland 2020

Wind actions can have a great impact on both bridges and traffic on bridges. However, structures designed to shelter the traffic from wind can influence the aerodynamic performance of the bridge deck, especially for long-span bridges. This study compares the effect of non-perforated walls and perforated walls used as wind barriers for traffic by conducting Computational Fluid Dynamics (CFD) simulations on three-dimensional geometries of a four-lane bridge deck. Steady-state simulations employ the Reynolds-Averaged Navier Stokes (RANS) method with the k-epsilon turbulence model and all simulations use parallel computing. An open-sourced software OpenFOAM is used.


Simulation Of Traffic Loading On Long Span Bridges, Hang Zhang, Michael Quilligan Aug 2020

Simulation Of Traffic Loading On Long Span Bridges, Hang Zhang, Michael Quilligan

Civil Engineering Research in Ireland 2020

Existing long span load models have typically been developed using a number of conservative assumptions, and as such are more applicable to the design of new bridges rather than the assessment of existing structures. Excessive conservatism in such assumptions can lead to expensive and unnecessary interventions in existing bridges. Furthermore, existing load models do not always allow for correlations in traffic weights and vehicle positions on the bridge.


Thermodynamic Cement Hydration Modelling Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer Aug 2020

Thermodynamic Cement Hydration Modelling Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer

Civil Engineering Research in Ireland 2020

Thermodynamics have been successfully applied to the field of cement hydration science to predict the formation of phase assemblages and pore solution chemistry. For any cement hydration model to be accepted, it must provide accurate forecasts of which solids may form and how the cement will dissolve over time. This is particularly important for the ongoing development of new sustainable cements and understanding their hydration behaviour in service.


Computational Modelling Of Next Generation Materials For Steel Catenary Risers In The Offshore Industry, Padraic O'Donoghue, Ronan Devaney, Seán B. Leen Aug 2020

Computational Modelling Of Next Generation Materials For Steel Catenary Risers In The Offshore Industry, Padraic O'Donoghue, Ronan Devaney, Seán B. Leen

Civil Engineering Research in Ireland 2020

Production risers are used to conduct oil or gas from the wellhead to an offshore production facility. Due to technical challenges with flexible marine pipe at large depths, there has been a move to steel catenary risers (SCRs) in recent years, due to the availability of high strength low alloy (HSLA) steels, such as bainitic X100. HSLA steels make SCRs a viable option for deep water due to the reduction in complexity and hence cost, compared to flexible pipes. However fatigue response is an important factor in their design, particularly in the vicinity of welded connections.


Fish Farm Monitoring For Blue Growth, Vikram Pakrashi, Wenliang Qiu, Michael O'Byrne, Paul Cahill, Basuraj Bhowmik, Bidisha Ghosh Aug 2020

Fish Farm Monitoring For Blue Growth, Vikram Pakrashi, Wenliang Qiu, Michael O'Byrne, Paul Cahill, Basuraj Bhowmik, Bidisha Ghosh

Civil Engineering Research in Ireland 2020

Fish farms are structures which require unique monitoring. There are problems related to marine growth and overloading, along with breaks in nets. These can lead to damage in fish or attacks of worms, which in turn is responsible for loss of fish. Such loss can be extremely expensive.


Instrumented Trains As A Probe For Structural Health Monitoring Of Railway Infrastructure, Vikram Pakrashi, Claire Mcgeown, Rohit Chawla, David Hester, Alexandra Micu, Eugene O'Brien Aug 2020

Instrumented Trains As A Probe For Structural Health Monitoring Of Railway Infrastructure, Vikram Pakrashi, Claire Mcgeown, Rohit Chawla, David Hester, Alexandra Micu, Eugene O'Brien

Civil Engineering Research in Ireland 2020

Railway infrastructure throughout the world is degrading and the Structural Health Monitoring (SHM) of this infrastructure can be effective. As a part of INTERREG project SIRMA, it is being investigated in instrumented trains can be used as a moving sensor for SHM of bridges and rail lines. Off-the-shelf calibrated sensors will be connected to trains and the instrumentation regime will be decided based on each SHM need. Output-only algorithms for anomaly detection and system identification will be implemented. Damage Sensitive Features (DSF) will be investigated to assess the best markers for the proposed SHM. A combined set of instrumentation and …


Implementation Of A Low-Cost Rtk Positioning System For Drone-Assisted Structural Inspections, Aidan Keaveney, Patrick Mcgetrick Aug 2020

Implementation Of A Low-Cost Rtk Positioning System For Drone-Assisted Structural Inspections, Aidan Keaveney, Patrick Mcgetrick

Civil Engineering Research in Ireland 2020

Technological developments of unmanned aerial vehicles (UAVs) have been rapid and significant in recent years, and thus the scope of use has increased across a broad spectrum of industries, including the fields of structural and civil engineering. A key part of structural engineering is ensuring that a structure can be inspected during its service life to determine if there is any defect that could diminish its structural integrity. In practice, the procedures involved in such inspections to locate defects can be dangerous, time consuming and expensive to conduct. The aim of this study is to establish a system that is …


Potential Of A Low-Calcium Fly Ash (Fa) For The Production Of Alkali-Activated Materials., Omar Alelweet, Sara Pavia Aug 2020

Potential Of A Low-Calcium Fly Ash (Fa) For The Production Of Alkali-Activated Materials., Omar Alelweet, Sara Pavia

Civil Engineering Research in Ireland 2020

Coal-FA from power stations is an industrial waste abundantly produced in the world. FA can be used as a silicate precursor, and activated with an alkali-metal source to produce alkali-activated materials (AAMs). AAMs are more sustainable than other traditional products, as the use of waste for their production, reduces carbon emissions, and raw materials and energy consumption. This paper studies the properties, composition and reactivity of an Irish FA to establish its potential for the production of AAMs. The results clearly evidenced that the FA is reactive. It is ultrafine, it has a high specific surface area and is partially …


Preliminary Investigation On The Use Of Dolomitic Quarry By-Product Powders In Grout For Self-Compacting Concrete Applications, Ahmed Abdalqader, Katrina Wilson, Neil Thornton, Kieran Mchugh, Mohammed Sonebi, Su Taylor Aug 2020

Preliminary Investigation On The Use Of Dolomitic Quarry By-Product Powders In Grout For Self-Compacting Concrete Applications, Ahmed Abdalqader, Katrina Wilson, Neil Thornton, Kieran Mchugh, Mohammed Sonebi, Su Taylor

Civil Engineering Research in Ireland 2020

Self-compacting concrete (SCC) flows under its own weight without requiring external vibration for compaction. This is very useful in applications where normal vibrated concrete cannot be used such as narrow forms and reinforcement congested members. To attain the self-compacting property, it is required that the concrete have adequate viscosity, high deformability and high resistance to segregation. This is can be achieved by adding mineral admixtures (fillers) and/or viscosity modifying agents (VMAs). The former is the main practice in Europe and processed limestone powder is the most commonly used filler in the production of SCC. However, the quarrying process of the …


Durability And Sustainability Of Pavement Quality Concrete In Airfields, Aidan Fogarty, Mark Richardson Aug 2020

Durability And Sustainability Of Pavement Quality Concrete In Airfields, Aidan Fogarty, Mark Richardson

Civil Engineering Research in Ireland 2020

Direct emissions from the aviation industry accounts for 2% of global emissions. If global aviation was a country it would be in the top 10 emitters. The International Civil Aviation Organization (ICAO) forecasts that emissions could grow by a further 300-700% by 2050. In 2010 global cement manufacture released 3270 million metric tonnes of CO2 into our atmosphere. In 2020 that amount is estimated to be 4370 million metric tonnes of CO2. This will account for around 8% of global CO2. Replacing Portland cement with 70% GGBS in concrete reduces the carbon footprint associated with the cement content in concrete. …


Maximising The Potential Use Of Ground Granulated Blast-Furnace Slag (Ggbs) In Cement: An Irish Investigation, Brendan Higgins, Michael Curran, John P. Spillane Aug 2020

Maximising The Potential Use Of Ground Granulated Blast-Furnace Slag (Ggbs) In Cement: An Irish Investigation, Brendan Higgins, Michael Curran, John P. Spillane

Civil Engineering Research in Ireland 2020

The production of cement is estimated to account for around 8% of carbon dioxide (CO2) emissions worldwide, and the Irish construction industry yields fifteen million tonnes of CO2 annually. Measures must be employed to reduce these emissions by incorporating less CO2 intensive admixtures such as blast-furnace slag, however, the Irish construction industry can often be resistant to change. Therefore, this study aims to investigate the potential implementation of ground granulated blast-furnace slag (GGBS) into the use of cement in Ireland, on the basis of maximisation over optimisation. This research is based on the hypothesis that if GGBS produces drastically less …


Predicting Mortar Compressive Strength Using Hydcem, Ewoma Ogoro, Niall Holmes, Denis Kelliher, Mark Tyrer Aug 2020

Predicting Mortar Compressive Strength Using Hydcem, Ewoma Ogoro, Niall Holmes, Denis Kelliher, Mark Tyrer

Civil Engineering Research in Ireland 2020

The compressive strength of mortar is a significant property that will influence its performance in concrete or masonry. Being able to accurately model and predict the mortar compressive strength would be of great benefit to suppliers and end users alike that could possibly reduce the need for multiple physical testing.


Environmental Impact On Corrosion Rates Of Steel Piles Employed In Marine Environment, Rebecca Galvin, Ciaran Hanley, Kieran Ruane, John J. Murphy, Vesna Jaksic Aug 2020

Environmental Impact On Corrosion Rates Of Steel Piles Employed In Marine Environment, Rebecca Galvin, Ciaran Hanley, Kieran Ruane, John J. Murphy, Vesna Jaksic

Civil Engineering Research in Ireland 2020

Steel piles employed in a marine environment will deteriorate over their lifetime owing to corrosive effects of the sea. The focus of this research are the causes, effects, and magnitude of the corrosion of steel piles, supporting an on shore jetty. The governing codes of practice in Ireland for designing steel piles are: (i) European Standard I.S. EN 1993-5 – Eurocode 3: Design of steel structures - Part 5: Piling, and (ii) I.S. EN 1993-1-1 – Eurocode 3: Design of steel structures - Part 1-1: General rules and rules for buildings. These codes are discussed, including all aspects of the …


Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao Aug 2020

Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao

Journal of Electrochemistry

Zinc-air battery has attracted great attention from researchers due to its high energy density and power density, which is expected to be widely used in energy conversion and storage. Air electrode as the core area of oxygen catalytic reaction is the focus of the entire zinc-air battery research. Recently, many research achievements have been made in non-noble metal bifunctional catalysts/electrodes with high activity, low cost and abundant species. In this review, we mainly focus on the reaction mechanism and the recent progress in non-noble metal oxide catalyst, carbon-based catalyst, and carbon-based transition metal compound composite and self-supporting electrode. In addition, …


Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia Fan, Na Han, Yan-Guang Li Aug 2020

Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia Fan, Na Han, Yan-Guang Li

Journal of Electrochemistry

Electrochemical carbon dioxide reduction (CO2RR) is an appealing approach to convert atmospheric CO2 to value-added fuels and industrial chemicals, and may play an important role during the transition to a carbon-neutral economy. In order to make this technology commercially viable, it is essential to pursue CO2RR in flow reactors instead of conventional H-type reactors, and to combine electrocatalyst development with system engineering. In this review, we overview the cell configurations and performance advantages of the two types of flow reactors, analyze their shortcomings, and discuss the effects of their different components including gas diffusion electrode …


Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules, Jin-Han Li, Fang-Yi Cheng Aug 2020

Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules, Jin-Han Li, Fang-Yi Cheng

Journal of Electrochemistry

Reduction of stable molecules such as CO2 and N2 is important process in electrochemical energy conversion and storage technologies for electrofuels production. However, for the inert nature of CO2/N2 molecule and competitive proton reduction in conventional aqueous electrolytes, selective electrochemical carbon/nitrogen fixation suffers from high overpotential, low reaction rate and low selectivity. While addressing these issues has witnessed substantial advances in electrocatalysts, much less attention has been placed on the electrolytes, which play an important role in regulating the local environment and thus the performance of catalysts under operating conditions. Rational design of electrolytes has …


Electrochemical Energy Storage And Conversion Based On Organic Electrodes, Jian-Hang Huang, Xiao-Li Dong, Zhao-Wei Guo, Yuan-Yuan Ma, Yan-Rong Wang, Yong-Gang Wang Aug 2020

Electrochemical Energy Storage And Conversion Based On Organic Electrodes, Jian-Hang Huang, Xiao-Li Dong, Zhao-Wei Guo, Yuan-Yuan Ma, Yan-Rong Wang, Yong-Gang Wang

Journal of Electrochemistry

Aqueous batteries have been considered to be a competitive candidate for large-scale energy storage. However, most of aqueous batteries adopt inorganic electrode materials with metallic elements, which are based on the reversible insertion of metal ions, making their application being highly hindered by limited cycle life, environmental issue, high cost and low reserves. On the other hand, organic electrode materials offer the advantages of abundant reserves, tunable structures, renewability and environmental benignity. Furthermore, the wide internal space enables these organics to flexibly store various charge carriers. Organics have been investigated as the alternative to inorganic electrode materials. Herein, we review …


Large-Scale Flow In Micro Electrokinetic Turbulent Mixer, Keyi Nan, Zhongyan Hu, Wei Zhao, Kaige Wang, Jintao Bai, Guiren Wang Aug 2020

Large-Scale Flow In Micro Electrokinetic Turbulent Mixer, Keyi Nan, Zhongyan Hu, Wei Zhao, Kaige Wang, Jintao Bai, Guiren Wang

Faculty Publications

In the present work, we studied the three-dimensional (3D) mean flow field in a micro electrokinetic (μEK) turbulence based micromixer by micro particle imaging velocimetry (μPIV) with stereoscopic method. A large-scale solenoid-type 3D mean flow field has been observed. The extraordinarily fast mixing process of the μEK turbulent mixer can be primarily attributed to two steps. First, under the strong velocity fluctuations generated by μEK mechanism, the two fluids with different conductivity are highly mixed near the entrance, primarily at the low electric conductivity sides and bias to the bottom wall. Then, the well-mixed fluid in the local region convects …


Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang Aug 2020

Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

The electrochemical conversion of CO2 to chemical raw material for further utilization shows promising future to alleviate global warming and realize carbon cycle in nature, which is of great significance to the green chemistry and sustainable development. This review briefly introduces the advantages of CO2 electrochemical reduction (CO2ER) and its basic reaction principles, and summarizes the recent progress in a series of activity enhancement strategies based on nanosized metal catalysts. The influences of alloy effect, interface engineering, synergistic effect, surface defect engineering and support effect on the catalytic performance of nanosized metals for CO2ER …