scholarly journals Oxygen Evolution Activity of LaNbN2O-Based Photocatalysts Obtained from Nitridation of a Precursor Oxide Structurally Modified by Incorporating Volatile Elements

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 566
Author(s):  
Shwetharani Ramu ◽  
Takashi Hisatomi ◽  
Kazunari Domen
Keyword(s):  
Oxygen Evolution ◽  
Apparent Quantum Yield ◽  
Volatile Elements ◽  
New Approach ◽  
Long Wavelength ◽  
Agno3 Solution ◽  
Highly Active ◽  
Perovskite Type Oxide ◽  
Oxide Particles ◽  
Perovskite Type

The perovskite-type oxynitride LaNbN2O is a photocatalyst that can evolve oxygen from aqueous solutions in response to long-wavelength visible light. However, it is challenging to obtain active LaNbN2O because of the facile reduction of Nb5+ during the nitridation of the precursor materials. The present study attempted to synthesize a perovskite-type oxide La0.6Na0.4Zn0.4Nb0.6O3, containing equimolar amounts of La3+ and Nb5+ in addition to volatile Na+ and Zn2+, followed by the nitridation of this oxide to generate LaNbN2O. The obtained oxide was not the intended single-phase material but rather comprised a cuboid perovskite-type oxide similar to La0.5Na0.5Zn0.33Nb0.67O3 along with spherical LaNbO4 particles and other impurities. A brief nitridation was found to form a LaNbN2O-like shell structure having a light absorption onset of approximately 700 nm on the cuboid perovskite-type oxide particles. This LaNbN2O-based photocatalyst, when loaded with a CoOx cocatalyst, exhibited an apparent quantum yield of 1.7% at 420 nm during oxygen evolution reaction from an aqueous AgNO3 solution. This was more than double the values obtained from the nitridation products of LaNbO4 and LaKNaNbO5. The present work demonstrates a new approach to the design of precursor oxides that yield highly active LaNbN2O and suggests opportunities for developing efficient Nb-based perovskite oxynitride photocatalysts.

Efficient photocatalytic oxygen evolution using BaTaO2N obtained from nitridation of perovskite-type oxide

2020 ◽  
Vol 8 (3) ◽  
pp. 1127-1130 ◽  
Author(s):  
Shraddha Jadhav ◽  
Shuta Hasegawa ◽  
Takashi Hisatomi ◽  
Zheng Wang ◽  
Jeongsuk Seo ◽  
...  
Keyword(s):  
Oxygen Evolution ◽  
Perovskite Type Oxide ◽  
Perovskite Type

Designing stoichiometric, isostructural precursor oxides opens opportunities for the development of (oxy)nitride photocatalysts.

A new approach to treatment of stomatitis in experiments on white rats (experimental research)

2018 ◽  
pp. 168-173
Author(s):  
Е.Б. Ганина ◽  
Ю.В. Червинец ◽  
Н.В. Грудинин ◽  
В.Г. Шестакова ◽  
В.М. Червинец ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Oral Cavity ◽  
Experimental Research ◽  
Quantitative Composition ◽  
Oral Diseases ◽  
New Approach ◽  
Highly Active ◽  
White Rats ◽  
Before And After ◽  
Intact Rats

Цель исследования - охарактеризовать микробиологическую картину стоматита до и после его лечения высокоактивными культурами лактобацилл, дать оценку эффективности их применения при экспериментальном стоматите. Методика. Опыты проводились на 32 самках беспородных белых крыс массой 230 г. Моделирование стоматита включало 2 этапа: моделирование травматического стоматита и воспроизведение бактериального стоматита на базе травматического. У крыс контрольной и опытных серий на всех этапах эксперимента брали мазки с поверхности десен для характеристики микробиоценоза ротовой полости. Результаты. После обработки слизистой оболочки полости рта (СОПР) культурой патогенного штамма Staphylococcus aureus существенно снизились частота встречаемости и количество условно-патогенных микроорганизмов. Лечение стоматита у крыс культурами лактобацилл ( Lactobacillus 11 зв., Lactobacillus 2 п.рта, Lactobacillus 24 д.ст.) и их комбинацией приводило к снижению распространенности S. aureus вплоть до его исчезновения, а также к нормализации количества условно-патогенной микробиоты. Заключение. Исследования показали эффективность использования отдельных высокоактивных штаммов лактобацилл или их комбинации при лечении заболеваний СОПР, в частности бактериального стоматита. Aim. To characterize the microbiological picture of stomatitis in intact rats before and after the treatment with highly active cultured lactobacilli and to evaluate the effectiveness of this treatment in experiments on white rats. Methods. Experiments were carried out on 32 mongrel female white rats weighing 230 g. Smears were taken from the gum surface of control and experimental rats at all stages of the experiment to characterize the oral cavity microbiocenosis. Results. After treatment of the oral cavity with cultured Staphylococcus aureus , the occurrence and quantity of opportunistic microorganisms significantly decreased. The treatment of stomatitis in rats with cultured lactobacillus ( Lactobacillus 11 zv., Lactobacillus 2 p.r., Lactobacillus 24 d.st. and their combination) led to a decrease in S. aureus prevalence up to its extinction and to normalization of the quantitative composition of opportunistic microbiota. Conclusions. The study showed the effieacy of highly active lactobacillus strains individually or their combinations in the treatment of oral diseases, in particular, bacterial stomatitis.

Controllable growth of graphdiyne layered nanosheets for high-performance water oxidation

2021 ◽  
Author(s):  
Shuya Zhao ◽  
Yurui Xue ◽  
Zhongqiang Wang ◽  
Zhiqiang Zheng ◽  
Xiaoyu Luan ◽  
...  
Keyword(s):  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Water Oxidation ◽  
High Performance ◽  
Low Cost ◽  
Highly Active ◽  
Controllable Growth

Developing highly active, stable and low-cost electrocatalysts capable of an efficient oxygen evolution reaction (OER) is urgent and challenging.

scholarly journals Investigation of antioxidant and anticancer activities of unsaturated oligo-galacturonic acids produced by pectinase of Streptomyces hydrogenans YAM1

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Afrouzossadat Hosseini Abari ◽  
Hamed Amini Rourani ◽  
Seyed Mahdi Ghasemi ◽  
Hyun Kim ◽  
Yun-Gon Kim
Keyword(s):  
Radical Scavenging Activity ◽  
Flow Cytometric Analysis ◽  
Radical Scavenging ◽  
Anticancer Activities ◽  
Pectin Degradation ◽  
New Approach ◽  
Flight Mass Spectrometry ◽  
Highly Active ◽  
Carbohydrate Polymer ◽  
Pectinase Activity

AbstractPectin, a diverse carbohydrate polymer in plants consists of a core of α-1,4-linked D-galacturonic acid units, includes a vast portion of fruit and agricultural wastes. Using the wastes to produce beneficial compounds is a new approach to control the negative environmental impacts of the accumulated wastes. In the present study, we report a pectinase producing bacterium Streptomyces hydrogenans YAM1 and evaluate antioxidative and anticancer effects of the oligosaccharides obtained from pectin degradation. The production of oligosaccharides due to pectinase activity was detected by thin layer chromatography (TLC) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Our results revealed that S. hydrogenans YAM1 can degrade pectin to unsaturated pectic oligo-galacturonic acids (POS) with approximately 93% radical scavenging activity in 20 mg/mL which it is more than 50% of the same concentration of pectin. Flow cytometric analysis revealed that MCF-7 cells viability decreased more than 32 and 92% following treatment with 6 and 20 mg/mL POS after 24 h, respectively. It is suggested that pectin degradation by S. hydrogenans YAM1 is not only a new approach to produce highly active compounds from fruit wastes, but also is an effective method to remove fibrous pollutants from different environments.

High-performance anion exchange membrane alkaline seawater electrolysis

2021 ◽  
Author(s):  
Yoo Sei Park ◽  
Jooyoung Lee ◽  
Myeong-Je Jang ◽  
Juchan Yang ◽  
Jae Hoon Jeong ◽  
...  
Keyword(s):  
Anion Exchange ◽  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
High Performance ◽  
Anion Exchange Membrane ◽  
Hydrogen Energy ◽  
Highly Active ◽  
Production Of Hydrogen ◽  
Exchange Membrane ◽  
Seawater Electrolysis

Seawater electrolysis is a promising technology for the production of hydrogen energy and seawater desalination. To produce hydrogen energy through seawater electrolysis, highly active electrocatalysts for the oxygen evolution reaction...

Selenic Acid Etching Assisted Vacancy Engineering for Designing Highly Active Electrocatalysts toward the Oxygen Evolution Reaction

2021 ◽  
Vol 33 (14) ◽  
pp. 2007523
Author(s):  
Lin Zhang ◽  
Chengjie Lu ◽  
Fei Ye ◽  
Ruilvjing Pang ◽  
Yang Liu ◽  
...  
Keyword(s):  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Acid Etching ◽  
Selenic Acid ◽  
Highly Active
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