Decarbonizing N 2 conversion is particularly challenging, but essential for sustainable development of industry and agriculture. Herein, we achieve electrocatalytic activation/reduction of N 2 on X/Fe−N−C (X=Pd, Ir an...
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Decarbonizing N 2 conversion is particularly challenging, but essential for sustainable development of industry and agriculture. Herein, we achieve electrocatalytic activation/reduction of N 2 on X/Fe−N−C (X=Pd, Ir and Pt) dual-atom catalysts under ambient condition. We provide solid experimental evidence that local hydrogen radical (H*) generated on the X site of the X/Fe−N−C catalysts can participate in the activation/reduction of N 2 adsorbed on the Fe site. More importantly, we reveal that the reactivity of X/Fe−N−C catalysts for N 2 activation/reduction can be well adjusted by the activity of H* generated on the X site, i.e., the interaction between the X−H bond. Specifically, X/Fe−N−C catalyst with the weakest X−H bonding exhibits the highest H* activity, which is beneficial to the subsequent cleavage of X−H bond for N 2 hydrogenation. With the most active H*, the Pd/Fe dual-atom site promotes the turnover frequency of N 2 reduction by up to 10 times compared with the pristine Fe site.
Optical beams with orbital angular momentum (OAM) have numerous potential applications, but the means used for their generation often lack crucial on-demand control. In this work, we present a mechanism of converting ...
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The state-of-the-art studies on single-phase flow and hear transfer in narrow rectangular channels shows some difference with the conventional theory. In this paper, the experimental study of vertical upward flow resi...
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Vertical-axis wind turbines(VAWTs)have been widely used in urban environments,which contain dust and experience strong ***,airfoils for VAWTs in urban environments have received considerably less research attention th...
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Vertical-axis wind turbines(VAWTs)have been widely used in urban environments,which contain dust and experience strong ***,airfoils for VAWTs in urban environments have received considerably less research attention than those for horizontal-axis wind turbines(HAWTs).In this study,the sensitivity of a new VAWT airfoil developed at the Lanzhou University of Technology(LUT)to roughness was investigated via a wind tunnel *** results show that the LUT airfoil is less sensitive to roughness at a roughness height of<0.35 ***,the drag bucket of the LUT airfoil decreases with increasing roughness ***,the loads on the LUT airfoil during dynamic stall were studied at different turbulence intensities using a numerical method at a tip-speed ratio of *** the stall,the turbulence intensity did not considerably affect the normal or tangential force coefficients of the LUT ***,after the stall,the normal force coefficient varied obviously at low turbulence ***,as the turbulence intensity increased,the normal and tangential force coefficients decreased rapidly,particularly in the downwind region of the VAWT.
To investigate Counter-Current flow (CCF) characteristics in the Pressurizer Surge Line (PZR SL) assembly of the large advanced passive nuclear reactors, steam-water CCF experiments are carried out on a stainless stee...
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To investigate Counter-Current flow (CCF) characteristics in the Pressurizer Surge Line (PZR SL) assembly of the large advanced passive nuclear reactors, steam-water CCF experiments are carried out on a stainless steel test section, which is a 1:4 scaled-down model of the AP1000 PZR SL assembly. The inner diameter of the test PZR SL pipe is 90 mm, which also belongs to the large-diameter pipes, as same as the prototype PZR SL pipe, in the field of Counter-Current flow Limitation (CCFL) researches. The present steam-water CCFL experiments are conducted under normal pressure and saturated temperature, with the PZR simulator collapse water level ranging from 350 to 900 mm. CCFL becomes severer at higher steam flow rate, and the most limiting CCFL effect locates between the PZR simulator bottom head and the vertical part of PZR SL pipe. The onset of CCFL and zero liquid penetration (ZP) are two critical conditions in the CCF development process, dividing the process into three stages: Before-CCFL, Partial-CCFL, and CCFL-ZP. According to the local CCFL conditions, the development of the CCFL process is also divided into four-regions since onset of CCFL. The present steam-water CCF data are well normalized in terms of dimensionless Kutateladze (Ku) numbers, and a Ku-type empirical partial CCFL correlation is developed. The comparisons of the present CCF data and partial CCFL correlation with the CCF data and correlations of former experiment researches validate that the present empirical partial CCFL correlation is conservative to predict steam-water partial CCFL in the prototype PZR SL assembly of the large advanced passive nuclear reactors.
Laser-induced breakdown spectroscopy (LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental composition. LIBS has been extensively studied and developed due to the n...
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Laser-induced breakdown spectroscopy (LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental composition. LIBS has been extensively studied and developed due to the non-contact, fast response, high sensitivity, real-time and multi-elemental detection features. The development and applications of LIBS technique in Asia are summarized and discussed in this review paper. The researchers in Asia work on different aspects of the LIBS study in fundamentals, data processing and modeling, applications and instrumentations. According to the current research status, the challenges, opportunities and further development of LIBS technique in Asia are also evaluated to promote LIBS research and its applications.
Laser-induced breakdown spectroscopy(LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental *** has been extensively studied and developed due to the non-contact,fast...
Laser-induced breakdown spectroscopy(LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental *** has been extensively studied and developed due to the non-contact,fast response,high sensitivity,real-time and multi-elemental detection *** development and applications of LIBS technique in Asia are summarized and discussed in this review *** researchers in Asia work on different aspects of the LIBS study in fundamentals,data processing and modeling,applications and *** to the current research status,the challenges,opportunities and further development of LIBS technique in Asia are also evaluated to promote LIBS research and its applications.
Liquid drops hit against solid surface, which has an enormous influence on the mechanical properties of base solid surface during its service. Impact of the droplet makes the solid surface and some internal section of...
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Some coking plants discharge coke-oven gas to the environment,this pollute the *** order to solute the problem,the paper proposed a method:using coke-oven gas instead of light oil to ignite the *** virtue of doing thi...
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