ADVANCED MATERIALS
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2021
·Vol. 33
·期 11
·2005587
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IF 30.849
Ke Wang,Hongfang Du,Song He,Lei Liu,Kai Yang,Jinmeng Sun,Yuhang Liu,Zhuzhu Du,Linghai Xie,Wei Ai,Wei Huang
Layered γ-type iron oxyhydroxide (γ-FeOOH) is a promising material for various applications; however, its sheet-shaped structure often suffers from instability that results in aggregation and leads to inferior performance. Herein, a kinetically controlled hydrolysis strategy is proposed for the scalable synthesis of γ-FeOOH nanosheets arrays (NAs) with enhanced structural stability on diverse substrates at ambient conditions. The underlying mechanisms for the growth of γ-FeOOH NAs associated with their structural evolution are systematically elucidated by alkalinity-controlled synthesis and time-dependent experiments. As a proof-of-concept application, γ-FeOOH NAs are developed as electrocatalysts for the oxygen evolution reaction (OER), where the sample grown on nickel foam (NF) exhibits superior performance of high catalytic current density, small Tafel slope, and exceptional durability, which is among the top level of FeOOH-based electrocatalysts. Density functional theory calculations suggest that γ-NiOOH in situ generated from the electrooxidation of NF would induce charge accumulation on the Fe sites of γ-FeOOH NAs, leading to enhanced OER intermediates adsorption for water splitting. This work affords a new technique to rationally design and synthesize γ-FeOOH NAs for various applications.
研究领域:
材料科学
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电化学
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理论计算
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产品关联
DOI
PubMed
高影响因子
RSC Advances
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2020
·Vol. 10
·期 19
·11188-11199
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IF 3.119
Liuming Song,Ruizhen Wang,Jianchun Jiang,Junming Xu,Jinsheng Gou
A cost-efficient methodology was developed for a two-step removal of hemicellulose from lignocellulosic biomass, thereby yielding C5 sugars, further separated residue, and high purity cellulose as well as lignin. In the first step of the process, an oxalic acid (OA)-assisted hydrolysis pretreatment was conducted for the selective decomposition of hemicellulose to C5 sugars. The optimized process conditions were as follows: temperature: 160 °C, OA concentration: 1%, holding time: 10 min. Under these conditions, various monosaccharides and other intermediates were obtained and more than 98.32% of the hemicellulose was removed from the original poplar. In the second step of the process, to extract lignin, a low concentration of sulfuric acid was used as a catalyst during the treatment of samples in a γ-valerolactone/H2O system; more than 91.57% lignin was removed, 82.99% cellulose was retained in the solid cellulose-rich substrates, and 94.45% (i.e., high-purity) cellulose was obtained. This method can be used for efficient fractionation of hemicellulose, cellulose, and lignin with the aim of achieving high value utilization of the entire biomass.
研究领域:
生物化学
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生物质能
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可再生资源工程
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DOI
PubMed
高影响因子
Journal of Water Process Engineering
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2020
·
IF 3.465
Yu Li,Luchao Wu,Yun Wang,Peng Ke,Jie Xu,Baohong Guan
Ozone decomposition into free radicals, which can be facilitated by enhancing electron transfer between ozone and catalyst, is an important segment in catalytic ozonation. We doped cerium uniformly on γ-Al 2 O 3 with an impregnation–calcination method to enhance electron transfer in catalytic ozonation of phenol in aqueous solution. The removal efficiency of phenol is raised from 39.7% by ozonation alone to 46.3% by catalytic ozonation with Ce/Al 2 O 3 in 50 min reaction. A higher Ce 3+ /Ce 4+ ratio in Ce/Al 2 O 3 witnesses a higher electron transfer rate in catalytic ozonation and thus a higher degradation efficiency of phenol, illustrating that the activity of Ce/Al 2 O 3 depends on the valence state of Ce. The electron transfer cycle is formed by the electron donation from Ce 3+ to ozone molecule and the electron acceptance of Ce 4+ from adjacent lattice oxygen. After getting the electron, the ozone molecule is decomposed to generate free radical of ·OH on the surface of Ce/Al 2 O 3 . The continuous flow experiments exhibit a stable and high catalytic activity of Ce/Al 2 O 3 for catalytic ozonation, implying the feasibility in practical application.
研究领域:
环境科学
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催化材料
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2022
·
IF 3.898
Zhaofeng Zhang,Juanjuan Ding,Min Wu,Bochao Liu,Huiwen Song,Shengping You,Wei Qi,Rongxin Su,Zhimin He
γ-Aminobutyric acid (GABA), a natural non-protein amino acid, plays an irreplaceable role in regulating the life activities of organisms. Nowadays, the separation and purification of food-grade GABA from fermentation broth is still a great challenge. This research utilized monosodium glutamate as a substrate for the production of high-purity GABA via an integrated process incorporating fermentation, purification, and crystallization. Firstly, 147 g·L −1 GABA with a yield of 99.8% was achieved through fed-batch fermentation by Lactobacillus brevis CE701. Secondly, three integrated purification methods by ethanol precipitation were compared, and crude GABA with a purity of 89.85% was obtained by the optimized method. Thirdly, GABA crystals with a purity of 98.69% and a yield of 60% were further obtained through a designed crystallization process. Furthermore, the GABA industrial production process model was established by Superproper Designer V10 software, and material balance and economic analysis were carried out. Ethanol used in the process was recovered with a recovery of 98.79% through Aspen simulated extractive distillation. Then the fixed investment (equipment purchase and installation costs) for an annual production of 80 t GABA will be about 833000 USD; the total annual production cost (raw material cost and utility cost) will be about 641000 USD. The annual sale of GABA may be at the range of 2400000–4000000 USD and the payback period will be about 1–2 year. This integrated process provides a potential way for the industrial-scale production of food-grade GABA.
研究领域:
生物工程
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食品科学
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DOI
高影响因子
MATERIALS RESEARCH BULLETIN
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2018
·
IF 2.873
Shuangqiang Yue,Mu Gu,Xiaolin Liu,Fengrui Li,Juannan Zhang,Bo Liu,Shiming Huang,Chen Ni
A fast scintillation crystal, γ-CuBr, was successfully grown by hydrothermal method with NH 4 Br mineralizer. The element mole ratio of the Cu/Br crystal was about 0.91 caused by the crystal grown in a rich bromine environment. Under ultraviolet excitation, the crystal exhibited an intense 420 nm emission, a shoulder emission at 428 nm and a weak broadband emission at 560 nm, which could be related to free exciton recombination, Cu and Br vacancies, respectively. Furthermore, the X-ray excited optical luminescence of the crystal was first reported, and a strong 430 nm emission was observed. The analysis of luminescence decay kinetics revealed that the 430 nm emission is composed of two components with an average decay time of 36.9 ns. It means that the γ-CuBr crystal is a promising candidate for applications in fast radiation detection.
研究领域:
材料科学
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物理学
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产品关联
DOI
高影响因子
CORROSION SCIENCE
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2018
·
IF 4.862
Lian-Kui Wu,Wei-Yao Wu,Jia-Lin Song,Guang-Ya Hou,Hua-Zhen Cao,Yi-Ping Tang,Guo-Qu Zheng
Thickness controllable SiO 2 film was prepared on γ-TiAl alloy by cathodic electrodeposition . The oxidation behaviour of the specimens at 900 °C was studied. The effects of SiO 2 electrodeposition parameters, such as electrolysis time and deposition current density, on the morphology, structure and high temperature oxidation performance of the film were investigated. Results shown during thermal oxidation, the electrodeposited SiO 2 film could react with the TiAl alloy to form an alumina- and silicon-enriched glass-like oxide scale, which can prevent the inward diffusion of oxygen from air to the film/alloy interface, resulting in the remarkable decreased oxidation rate of the alloy.
研究领域:
材料科学
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表面工程
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DOI
高影响因子
CATALYSIS LETTERS
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2020
·Vol. 150
·期 11
·3174-3183
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IF 2.482
Wang Xun-Qiang,Li He,Yuan Qi-Yue,Liu Xiao-Qin,Liu Ding-Hua
Abstract Polycarbonate diols (PCDLs) are intermediates used in the synthesis of polyurethanes (PU), and therefore their efficient and green synthesis is a necessity. In this work, KOH/K 2 CO 3 @ γ -Al 2 O 3 catalysts were prepared and employed in the synthesis of PCDLs. A 4 wt% KOH/40 wt% K 2 CO 3 @ γ -Al 2 O 3 catalyst and a DMC: 1,4-BDO molar ratio of 1.25:1 exhibited the best activity for the reaction and gave a PCDL yield of 95% with a molecular weight of 4527 g·mol −1 . Moreover, the catalyst could be reused 4 times without a significant loss of the catalytic activity in transesterification. The effects of the catalyst composition and reaction conditions on the synthesis of PCDLs were investigated. The results indicate that the catalyst amount and the molar ratio of DMC: 1,4-BDO can influence the purity of PCDLs. Graphic Abstract The reaction equation
Catalyst preparation
The synthesis of PCDLs using DMC and 1,4-BDO
研究领域:
材料科学
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催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
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2024
·
IF 6.5
Jinni Shen,Yuhua Zhong,Jianhan Lin,Haifeng Li,Chengwei Qiu,Xu Liu,Xun Wang,Rong Hu,Jinlin Long,Xuxu Wang,Zizhong Zhang
Photocatalytic water splitting on metal oxides often faces oxygen evolution inefficiency, reflecting the complex interplay of its two half-reactions. Strategies like heterojunctions, cocatalyst loading, or noble metal nanoparticles addition have been explored to address this. Using γ-Ga 2 O 3 nanosheets as a model, we uncovered the formation of −O-O- species as the key barrier to stoichiometric splitting. To tackle this, a strategy was devised, Sr-doping to inhibit surface peroxidation. The resultant Sr-doped γ-Ga 2 O 3 (Sr-Ga 2 O 3 ) significantly improved activity and stability, achieving balanced H 2 and O 2 production under 125 W mercury lamp light. Upon further enhancement with Rh/Cr 2 O 3 cocatalyst via photoreduction, the Sr-Ga 2 O 3 /(Rh/Cr 2 O 3 ) composite demonstrated a remarkable 8.7 mmol·g −1 ·h −1 H 2 and 4.4 mmol·g −1 ·h −1 O 2 evolution rate, 8.3 times higher than γ-Ga 2 O 3 alone, with a 34.1 % quantum efficiency under 260 nm light. This represents a record performance for Ga 2 O 3 -based photocatalytic water splitting. Mechanistically, Sr doping alters surface chemistry to favor direct oxygen release. Our study elucidates molecular-level insights into non-stoichiometric splitting mechanisms and offers a potent strategy to boost metal oxide photocatalysts’ water-splitting efficiency.
研究领域:
材料科学
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环境科学
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能源化学
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产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
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2019
·Vol. 16
·期 6
·2173-2180
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IF 1.074
Ming-Ye Yang,Bin-Bin Dong,Fei-Hong Wang,Xin Xu,Simeon Agathopoulos
This paper reports on the successful fabrication of α -Si 3 N 4 -nanowire/Y 2 Si 2 O 7 composite membranes with superhydrophobic properties, aiming to achieve a high performance in membrane distillation. The starting powder mixture of 87 wt% γ -Y 2 Si 2 O 7 , 5 wt% Si, 3 wt% LiYO 2 , and 5 wt% ferrocene catalyst was dispersed in a stable suspension, and after being tape-casted, it was sintered at 1300°C for 4 hours in order to obtain the composite membrane. α -Si 3 N 4 nanowires with a diameter of about 50 nm were formed, distributed uniformly on the surface and in the pores of the membrane and their presence greatly favored superhydrophobicity. After surface modification with a robust hydrophobic layer of SiNCO nanoparticles, strongly adhered to the surface of the produced membrane, a water contact angle of 153 o , was measured. Water desalination experiments, using a sweeping gas membrane distillation (SGMD) device, were conducted. High water flux of 11.91 L/m 2 /h was achieved for a 4 wt% NaCl feeding solution at 90°C. Stable water flux and rejection rates were recorded in long-term experiments (>500 hours) using the produced superhydrophobic composite membrane.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
MATERIALS & DESIGN
·
2015
·
IF 3.501
Chunde Jin,Qiufang Yao,Jingpeng Li,Bitao Fan,Qingfeng Sun
Magnetic γ-Fe 2 O 3 nanoparticles were successfully deposited on the surface of the bamboo via a coprecipitation process at room temperature. Spherical-like magnetic γ-Fe 2 O 3 nanoparticles with a diameter of about 17 nm displayed well superparamagnetic behavior and were chemically bonded to the bamboo surface through the combination of hydrogen groups. With further modification by 1H,1H,2H,2H-perfluorodecyltri ethoxysilane (FAS-17), magnetic γ-Fe 2 O 3 /bamboo composites (MBCs) expressed superhydrophobic performances to not only water but also common liquids like coffee, milk, ink, tea, and coke. When immersed into the corrosive solutions including strong acid (pH = 1), heavy alkaline (pH = 14), and salt with high concentration (5 M) for 24 h, superhydrophobic magnetic γ-Fe 2 O 3 /bamboo composites (SMBC) still remained magnetism as well as superhydrophobicity. Also, under harsh conditions like boiled at 100 °C for 4 h, frozen at − 40 °C for 24 h, SMBCs were kept a robust magnetism and superhydrophobicity. Additionally, SMBC was a typical ferromagnet and exhibited some microwave absorbabilities .
研究领域:
材料科学
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纳米技术
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化学工程
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产品关联
DOI
高影响因子
DRUG METABOLISM AND DISPOSITION
·
2018
·Vol. 46
·期 11
·1538-1545
·
IF 3.64
Jiangming Deng,Lianxia Guo,Baojian Wu
Human CYP2A6 (Cyp2a5 in mice) plays an important role in metabolism and detoxification of various drugs and chemicals. Here, we investigated a potential role of peroxisome proliferator-activated receptor γ (Ppar-γ) in circadian regulation of the Cyp2a5 enzyme. We first showed that Cyp2a5 mRNA and protein in mouse liver displayed robust circadian oscillations. Consistent with a circadian protein pattern, Cyp2a5-mediated 7-hydroxylation of coumarin was circadian time–dependent. Formation of 7-hydroxycoumarin was more extensive at a dosing time of Zeitgeber time 2 (ZT2) than that at ZT14. Interestingly, the nuclear receptor Ppar-γ was also a circadian gene. Circadian Ppar-γ protein level was strongly correlated with the Cyp2a5 mRNA level (r = 0.989). Furthermore, Ppar-γ activation (by a selective agonist, rosiglitazone) upregulated Cyp2a5 expression in Hepa-1c1c7 cells, whereas Ppar-γ knockdown downregulated Cyp2a5 expression. Also, Ppar-γ knockdown blunted the rhythmicity of Cyp2a5 mRNA in serum-shocked Hepa-1c1c7 cells. In addition, a combination of promoter truncation analysis, mobility shift, and chromatin immunoprecipitation assays revealed that Ppar-γ directly bound to a PPAR response element (i.e., the −1418- to −1396-bp region) within Cyp2a5 promoter and activated the gene transcription. Taken together, Ppar-γ was a transcriptional activator of Cyp2a5, and its rhythmic expression contributed to circadian expression of Cyp2a5.
研究领域:
药理学
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分子生物学
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昼夜节律生物学
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产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2022
·
IF 4.177
Yixuan Liu,Zhilin Yang,Hua Yang
Magnetic γ′-Fe4N has been considered as one of the most promising non-noble materials for the electrocatalysis of the oxygen evolution reaction (OER) due to its excellent magnetic properties, unique anti-perovskite-like structure, high chemical stability, and high intrinsic activity. Exploring environmentally friendly and efficient nitrogen sources instead of ammonia is still a huge challenge associated with obtaining pure γ′-Fe4N. In addition, it is widely acknowledged that the unique morphological and structural tuning of metal nitrides could effectively enhance their electrocatalytic capabilities. In this study, two kinds of magnetic γ′-Fe4N with different morphologies (cuboidal and rodlike) are obtained by combining facile solvent-regulated ferrous oxalate precursors with ethylenediamine-assisted thermal nitriding. The facile morphological tuning endows γ′-Fe4N with excellent soft magnetic properties while improving the activity toward OER. Specifically, the saturation magnetization of cuboidal γ′-Fe4N reaches up to 167.38 emu g–1. In addition, compared with the RuO2 benchmark for OER, cuboidal γ′-Fe4N shows more excellent OER electrocatalytic performance, showing an overpotential of 253 mV@10 mA cm–2 in 1.0 M KOH and a low Tafel slope (45 mV dec–1). This is of great significance for the non-ammonia synthesis of iron nitride and the development of non-noble-metal-based OER electrocatalysts.
研究领域:
材料科学
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电化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）