Construction of Six‐Oxygen‐Coordinated Single Ni Sites on g‐C 3 N 4 with Boron‐Oxo Species for Photocatalytic Water‐Activation‐Induced CO 2 Reduction

2021 ◽  
pp. 2105482
Author(s):  
Yuying Wang ◽  
Yang Qu ◽  
Binhong Qu ◽  
Linlu Bai ◽  
Yang Liu ◽  
...  
Keyword(s):  
2021 ◽  
Author(s):  
Tihomir Marjanac ◽  
Marina Čalogović ◽  
Karlo Bermanec ◽  
Ljerka Marjanac

Abstract Strong earthquake of M6.4 stroke Petrinja and neighbouring cities of Sisak and Glina in Croatia on December 29th 2020. It was preceded by two foreshocks of M5.2 and M5.0, and followed by a series of aftershocks of various magnitudes and intensities. We have analysed first 500 earthquakes and aftershocks of > M1.0 which occurred from December 28th 2020 to January 19th 2021, their frequency, focal depths, and coseismic surface phenomena. Correlation of focal depths revealed the source of earthquakes was faulting of hanging wall of a listric normal fault with NW-SE strike and dip towards NE. Major fault seems to have caused earthquakes with only minor magnitudes. The strongest two earthquakes of M6.4 and M5.2 were initiated on synthetic fault, whereas M5.0 earthquake was initiated on an antithetic fault. Almost 50% of all seismic energy of the first 500 analysed seismic events over M1.0 was released on 1 km and 10 km deep hypocentres. Focal mechanisms of major earthquakes and strong fore- and aftershocks indicate dextral-slip mechanism, which is also in accordance with the orientation of surface cracks, land faulting and sand volcano trains. Co-seismic surface phenomena are land cracks and fissures, land faults, sand volcanoes, eruptive springing of ground water, activation of landslides, and formation of dozens of collapse sinkholes which continued to form and grow for about a month following the major earthquake.


Weed Science ◽  
1995 ◽  
Vol 43 (1) ◽  
pp. 149-155 ◽  
Author(s):  
Terry R. Wright ◽  
Alex G. Ogg ◽  
E. Patrick Fuerst

Field experiments were conducted in 1992 and 1993 to determine the timing and amount of rainfall required to activate UCC-C4243 applied preemergence. UCC-C4243 at 0, 70, and 140 g ai ha−1was applied 1, 7, 14, and 21 d before 0.5 or 2 cm of simulated rainfall. Temporary rainshelters protected field plots from natural rainfall during the 21 d dry period. Herbicide activity was determined in the field by seeding lentil, wheat, common lambsquarters, and field pennycress and in the greenhouse by a sugarbeet bioassay of soil samples (0 to 3 cm depth) taken from all plots immediately before irrigation. UCC-C4243 did not injure wheat; however, lentil population was reduced when simulated rainfall occurred within 7 d after application. Lentil injury was greater with higher herbicide rate and higher water level. UCC-C4243 at 70 and 140 g ha−1reduced populations of both weed species by 75 and 90%, respectively, when either 0.5 or 2 cm simulated rainfall was received within 1 d after herbicide application. Weed control was reduced with a 21 d delay between herbicide application and water activation. The sugarbeet bioassay showed a linear decrease of herbicide activity over time and also with accumulated photosynthetically active radiation. After 17.9 d, herbicide activity on a dry soil surface decreased 50%. Laboratory investigations show that [14C]-UCC-C4243 on glass slides was photodegraded by near ultraviolet light (290 to 400 nm). Volatilization of14C-labeled herbicide from glass slides was less than 5% after exposure to turbulent air for 48 h.


2020 ◽  
Vol 160 ◽  
pp. 111828
Author(s):  
Andrej Žohar ◽  
Igor Lengar ◽  
Luka Snoj

2020 ◽  
Author(s):  
Ruichao Pang ◽  
Pengfei Tian ◽  
Hongliang Jiang ◽  
Minghui Zhu ◽  
Xiaozhi Su ◽  
...  

Abstract Unveiling the structural evolution and working mechanism of catalysts under realistic operating conditions is crucial for the design of efficient electrocatalysts for CO2 electroreduction, yet remains highly challenging. Here, by virtue of operando structural measurements at multiscale levels, it is identified under CO2 electroreduction conditions that an as-prepared CeO2/BiOCl precatalyst gradually evolves into CeOx/Bi interface structure with enriched Ce3+ species, which serves as the real catalytically active phase. The derived CeOx/Bi interface structure compared to pure Bi counterpart delivers substantially enhanced performance with a formate Faradaic efficiency approaching 90% for 24 hours in a wide potential window. The formate Faradaic efficiency can be further increased by using isotope D2O instead of H2O. Density functional theory calculations suggest that the regenerative CeOx/Bi interfacial sites can not only promote water activation to increase local *H species for CO2 protonation appropriately, but also stabilize the key intermediate *OCHO in formate pathway.


2017 ◽  
Vol 114 (24) ◽  
pp. 6191-6196 ◽  
Author(s):  
Myungwoon Lee ◽  
Tuo Wang ◽  
Olga V. Makhlynets ◽  
Yibing Wu ◽  
Nicholas F. Polizzi ◽  
...  

Throughout biology, amyloids are key structures in both functional proteins and the end product of pathologic protein misfolding. Amyloids might also represent an early precursor in the evolution of life because of their small molecular size and their ability to self-purify and catalyze chemical reactions. They also provide attractive backbones for advanced materials. When β-strands of an amyloid are arranged parallel and in register, side chains from the same position of each chain align, facilitating metal chelation when the residues are good ligands such as histidine. High-resolution structures of metalloamyloids are needed to understand the molecular bases of metal–amyloid interactions. Here we combine solid-state NMR and structural bioinformatics to determine the structure of a zinc-bound metalloamyloid that catalyzes ester hydrolysis. The peptide forms amphiphilic parallel β-sheets that assemble into stacked bilayers with alternating hydrophobic and polar interfaces. The hydrophobic interface is stabilized by apolar side chains from adjacent sheets, whereas the hydrated polar interface houses the Zn2+-binding histidines with binding geometries unusual in proteins. Each Zn2+ has two bis-coordinated histidine ligands, which bridge adjacent strands to form an infinite metal–ligand chain along the fibril axis. A third histidine completes the protein ligand environment, leaving a free site on the Zn2+ for water activation. This structure defines a class of materials, which we call metal–peptide frameworks. The structure reveals a delicate interplay through which metal ions stabilize the amyloid structure, which in turn shapes the ligand geometry and catalytic reactivity of Zn2+.


2018 ◽  
Vol 25 (1) ◽  
pp. 013520 ◽  
Author(s):  
Han Xu ◽  
Dingxin Liu ◽  
Wenjie Xia ◽  
Chen Chen ◽  
Weitao Wang ◽  
...  

2020 ◽  
Vol 1011 ◽  
pp. 151-157
Author(s):  
Sergey Khutorskoy ◽  
Denis Emelyanov ◽  
Alexander Matvievsky ◽  
Vasiliy Smirnov

The study results of the calcareous composites made with the use of activated mixing water are presented. Quicklime and slaked lime are used as lime binders. The mixing water was activated by the electric current and magnetic field in various modes. The effect of water activation on the physical and mechanical properties of slaked and quicklime composites and the resistance to the effects of the biological environment are studied. The water for mixing electromagnetic treatment effectiveness analysis is presented. The increase in the density of materials based on lime, trapped in activated water using ultrasound tests is proven. It was found that the mixing water activation affects the structure formation of composites and, under certain activation conditions, leads to an increase in such physical and mechanical parameters as strength and hardness. The positive effect of the mixing water activation on the lime-based materials’ resistance to microbial growth has been established, and the decrease in the growth of composites based on quicklime and slaked lime has been proved.


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