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91.
Xiangrong Ma Rui Dang Ning Yang Xiao Li Ya zhang Ying Gong Zhipan Liu Wei Guo Yuanyuan Zhang Chunyan Li 《International Journal of Hydrogen Energy》2021,46(44):22842-22851
The high cost of noble metal catalysts has been a great bottleneck for the catalyst industry. Using the noble metal at a single-atom level for catalytic applications could dramatically decrease the cost. The impacts of single Pt atoms on the photocatalytic performance of Ag3VO4 have been investigated and reported. In this report, single Pt atoms were anchored on the surface of Ag3VO4 (AVO) as a cocatalyst, and the resultant composite photocatalyst has been studied for photocatalytic H2 production from water driven by visible light. The as-prepared AVO particles are hollow nanospheres in the monoclinic phase with a bandgap of 2.20 eV. The light absorption edge of AVO/Pt is slightly red-shifted compared to that of the pristine AVO, indicating more visible light absorption of AVO/Pt. The XPS peaks of Ag, V, and Pt exhibit a significant shift after AVO and Pt get into contact, suggesting the strong interaction between the surface Ag and V atoms, and single Pt atoms. After 3-h illumination, the photocatalytic H2 evolution amount from AVO/Pt is improved up to 1400 μmol, which is 2.8 times that on the bare AVO. Such efficient photocatalytic H2 evolution on AVO/Pt is still maintained after five reaction cycles. The better photocatalytic performance of AVO/Pt has been attributed to the more efficient visible light utilization and the lower interfacial charge transfer resistance, as demonstrated in the DRS and EIS spectra. The presence of the surface Pt atoms also leads to a higher amount of reactive radicals, which could efficiently promote the surface redox reactions. 相似文献
92.
Kun Yang Huiling Wang Jin Huang Di Wu Manman Zhao Jing Ma Weiqing Sun 《International Journal of Food Science & Technology》2021,56(2):733-741
This study investigated the effects of direct current magnetic field (DC-MF) treatment time (1, 3, 5, 8 h) on properties of porcine myofibrillar protein (MP). Gel water-holding capacity increased from 83.40% to 87.20% when DC-MF-treatment time changed from 1-h to 8-h. The 3-h treatment time of DC-MF was found to promote MP unfolding, rearrangement and aggregation, leading to the loss of total sulfhydryl, the increase of reactive sulfhydryl, surface hydrophobicity, turbidity as well as the formation of MP clusters and the greater degree of crosslinking as compared with 0-h treatment, thus a firmer and more ordered MP gel network for trapping more water. However, excessive DC-MF treatment (8-h) weakened DC-MF effect on MP aggregation as well as gel network and texture. This study has shed light on the effects of DC-MF treatment time on MP properties and provides useful information for the application of DC-MF in the food industry. 相似文献
93.
Jodelle Degois Marc Veillette Patrick Poulin Benoit Lévesque Daniel Aubin Boualem Ouazia Mario Brisson François Maltais Caroline Duchaine 《Indoor air》2021,31(6):2213-2225
Indoor air quality is a major issue for public health, particularly in northern communities. In this extreme environment, adequate ventilation is crucial to provide a healthier indoor environment, especially in airtight dwellings. The main objective of the study is to assess the impact of ventilation systems and their optimization on microbial communities in bioaerosols and dust in 54 dwellings in Nunavik. Dwellings with three ventilation strategies (without mechanical ventilators, with heat recovery ventilators, and with energy recovery ventilators) were investigated before and after optimization of the ventilation systems. Indoor environmental conditions (temperature, relative humidity) and microbiological parameters (total bacteria, Aspergillus/Penicillium, endotoxin, and microbial biodiversity) were measured. Dust samples were collected in closed face cassettes with a polycarbonate filter using a micro-vacuum while a volume of 20 m3 of bioaerosols were collected on filters using a SASS3100 (airflow of 300 L/min). In bioaerosols, the median number of copies was 4.01 × 103 copies/m3 of air for total bacteria and 1.45 × 101 copies/m3 for Aspergillus/Penicillium. Median concentrations were 5.13 × 104 copies/mg of dust, 5.07 × 101 copies/mg, 9.98 EU/mg for total bacteria, Aspergillus/Penicillium and endotoxin concentrations, respectively. The main microorganisms were associated with human occupancy such as skin-related bacteria or yeasts, regardless of the type of ventilation. 相似文献
94.
Lei Wei Yumei Yang Ya-Na Yu Xiaomeng Wang Hongyan Liu Yanhong Lu Maixia Ma Yu Chen 《International Journal of Hydrogen Energy》2021,46(5):3811-3820
Hydrolytic dehydrogenation of ammonia borane (AB) driven by efficient catalysts has attracted considerable attention and is regarded as a promising strategy for hydrogen generation. Herein, RuP2 quantum dots supported on graphitic carbon nitride (g-C3N4) were successfully prepared by in-situ phosphorization, yielding a highly efficient photocatalyst toward AB hydrolysis. The catalysts were characterized by field-emission scanning electron microscopy, transmission electron microscopy, x-ray diffraction, x-ray photoelectron microscopy, inductively coupled plasma atomic emission spectroscopy, UV–visible diffuse reflectance spectroscopy and photoluminescence spectroscopy. A conventional water-displacement method was employed to record the hydrogen volume as a function of reaction time. Owing to visible-light irradiation, the initial turnover frequency of the AB hydrolysis was significantly enhanced by 110% (i.e., 134 min?1) at room temperature. Furthermore, the apparent activation energy decreased from 67.7 ± 0.9 to 47.6 ± 1.0 kJ mol?1. The photocatalytic hydrolysis mechanism and catalyst reusability were also investigated. 相似文献
95.
Steven Brady Kuzyk Kaitlyn Wiens Xiao Ma Vladimir Yurkov 《Journal of Great Lakes research》2021,47(3):567-582
While nutrient loading has affected all levels of Lake Winnipeg’s ecology, its greatest influence has likely been on the microbial community. In addition to eutrophication, zebra mussels (Dreissena polymorpha) have recently invaded the ecosystem and threaten food web dynamics. Their filter-feeding predation and association with bacteria, specifically phototrophs, was investigated. A sampling trip to Lake Winnipeg in October 2017, focused on the isolation, enumeration, and identification of aerobic anoxygenic phototrophs in littoral water, sediment, and tissues of mussels. Gimli, Patricia, and Grand beaches, separated by >15 km across the South Basin, had similar bacterial counts when cultivated on rich organic, BG-11, purple non-sulphur, and K2TeO3-supplemented media. Culture-based enumeration on rich organic medium revealed 1.74% of heterotrophs from littoral waters were aerobic anoxygenic phototrophs, and represented 13.98% within sediments. In contrast, 0.48, 1.15, and 0.16% of cultured heterotrophs were aerobic anoxygenic phototrophs within zebra mussel gill, gut, and gonadal tissues, respectively. High-throughput sequencing of bacterial 16S V4 rDNA maintained similar trends in respective bivalve organs, where 0.22, 1.13, and 0.20% of total 16S genes belonged to these phototrophs. Several Sphingomonadaceae isolates were recovered from gut tissues, all with filamentous morphology large enough for predation. Bioaccumulation of metals was also studied in D. polymorpha. All tested associated aerobic anoxygenic phototrophs were capable of resisting the metalloid oxide tellurite. The consistent distribution of aerobic anoxygenic phototrophs within microbial communities across Lake Winnipeg, and their predominance in the gut tissues of zebra mussels suggested bacterial consumption by this invasive species. 相似文献
96.
Liang Yong-chao Ma Rui-bo Zhou Li-li He Mu Tian Ze-an Mo Yun-fei 《Journal of Superconductivity and Novel Magnetism》2021,34(12):3377-3383
Journal of Superconductivity and Novel Magnetism - A molecular dynamics simulation has been conducted in Ni73Co27 and Ni74Co26 alloys during rapid solidification at the cooling rate of... 相似文献
97.
Yin Ma X.R. Wang Tong Li Jiawei Zhang Ji Gao Z.Y. Sun 《International Journal of Hydrogen Energy》2021,46(54):27330-27348
The present paper provides insights into the feasibility of using hydrogen and bioethanol blends as energy carriers in the foreseeable future upon discussions on the advantages and the disadvantages. The comprehensive overviews on the production, storage, and transportation of hydrogen and bioethanol have been made; and the current problems and potential solutions for the three stages have been summarized. Finally, the prospections on hydrogen and bioethanol could be expect optimistically. 相似文献
98.
Dehui Kong Wenting Zhao Yue Ma Hao Liang Xiaoyan Zhao 《International Journal of Food Science & Technology》2021,56(4):2041-2052
The effects of light-emitting diode (LED) illumination on the quality of fresh-cut cherry tomatoes were investigated. Tomatoes were exposed continuously to red, green, blue and white LED light for 7 days and control samples stored in darkness. Results showed that blue light treatment significantly led to more total soluble solids, lycopene concentration and individual phenolic compounds (chlorogenic acid, caffeic acid, rutin) after 7 days of storage. On day-5, green and blue light-treated tomatoes showed relatively higher firmness than samples treated by other lights and the control. At the early stage of storage, blue light could preserve the fresh flavour of tomatoes compared to other treatments. Overall, the blue light was most effective in the quality preservation of fresh-cut cherry tomatoes and could be used as a novel strategy in the preservation of fresh-cut fruits and vegetables during shelf life. 相似文献
99.
Yan Huang Honggang Lu Bingnan Wang Wenbo He Hongzhou Dong Lina Sui Zhixing Gan Shuai Ma Beili Pang Lifeng Dong Liyan Yu 《International Journal of Hydrogen Energy》2021,46(5):3530-3538
As a promising catalyst for solar hydrogen production, black phosphorus (BP) has received widespread attention due to variable band gaps, high carrier mobility, and strong light absorption performance. Herein, we use MoS2 as a cocatalyst to synthesize BP/MoS2 catalyst with polycrystalline BP to improve photocatalytic performance under visible light irradiation. A small amount of MoS2 can reduce the recombination of electron-hole pairs in the composite, increase carrier transport efficiency, and then improve photocatalytic performance. As expected, the 10/0.5 ratio of BP/MoS2 catalyst exhibits the highest photocatalytic hydrogen evolution performance with a hydrogen evolution rate of 575.4 μmol h?1 g?1, which is 2.5 times of pure BP. Based on the results above, a simple method is provided to synthesize low-cost black phosphorus-based photocatalysts. 相似文献
100.
Leonardo Sales Araujo Alessandra Vieira Guimarães Maísa Conceição Siqueira Matheus Campolina Mendes Loic Mallet Dilson Silva dos Santos Luiz Henrique de Almeida 《International Journal of Hydrogen Energy》2021,46(29):16164-16178
The nickel-base superalloy 718 is a precipitation hardened alloy widely used in the nuclear fuel assembly of pressurized water reactors (PWR). However, the alloy can experience failure due to hydrogen embrittlement (HE). The processing route can influence the microstructure of the material and, therefore, the HE degree. In particular, the size and distribution of the (Nb,Ti)C particles can be affected by the processing. In this regard, the objective of this work was to analyze the influence of cold and hot deformation processing routes on the development of the microstructure, and the consequences on mechanical properties and hydrogen embrittlement. Tensile samples were hydrogenated through gaseous charging and compared to non-hydrogenated samples. Characterization was performed via scanning and transmission electron microscopies, as well as electron backscattered diffraction. The processing was effective to promote significant variations in average grain size and length fraction of special Σ3n boundaries, as well as reduction of average (Nb,Ti)C particle size, being these changes more intense for the cold-rolled route. For the mechanical properties, on one side, the cold-rolled route presented the highest increase in ductility for non-hydrogenated samples, while, on the other side, had the highest degree of embrittlement under hydrogen. This dual behavior was attributed to the interaction of hydrogen with the (Nb,Ti)C particles and stringers and its ensuing influence on the fracture processes. 相似文献