Journal of Cleaner Production
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2017
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IF 5.715
Yuanan Hu,Yuanzhen He,Hefa Cheng
N -nitrosodimethylamine (NDMA), a highly toxic and carcinogenic disinfection byproduct , cannot be efficiently removed by conventional water treatment processes , while sorption by microporous minerals, followed by destruction with microwave irradiation has been developed as a promising alternative. This work examined the impact of surface cation density and type on sorption of NDMA on dealuminated ZSM-5 zeolites , and on microwave-induced degradation of the sorbed NDMA, as well as the non-thermal effect of microwave. NDMA sorption was found to increase with the framework Si/Al ratio of dealuminated ZSM-5 zeolites (i.e., decreasing density of surface cations), and was also influenced by the type of surface cations. Degradation of the sorbed NDMA proceeded faster with increases in the power level of microwave and in the micropores with higher densities of surface cations, which was attributed to the increases in the number and/or temperature of micro-scale “hot spots” formed by microwave dielectric superheating of the surface cations. The degradation rate of sorbed NDMA was also found to be inversely correlated with the hydration free energy of surface cations present in the zeolite micropores . The apparent activation energy estimated from the temperature dependence of NDMA degradation in the micropores under microwave irradiation was 18.2 kJ/mol, which is much lower than those of typical thermolysis reactions and is indicative of significant contribution from the non-thermal effect of microwave.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2018
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IF 5.158
Chengkai Zhai,Na Teng,Baohai Pan,Jing Chen,Fei Liu,Jin Zhu,Haining Na
Non-thermal effect of microwave is precisely revealed as an important factor to strengthen the hydrolysis of cellulose to sugar by a new method of synchronous cooling assisted microwave driving. Using this particular method, the thermal effect is mandatorily removed from the hydrolysis of cellulose. After systematic analysis of the hydrolysis of low crystalline regenerated cellulose (RC), the non-thermal effect of microwave is proved to strengthen hydrolysis. The enhancement of non-thermal effect effectively weaken the interaction between the hydroxyl groups of -O(2)H and -O(6)H, as well as strengthen interaction between the hydroxyl groups of -O(3)H and -O(5)H within one single molecular chain. It leads to the reduction of regularity of molecular chain and thus inhibits the recrystallization of RC. As a result, the efficiency of hydrolysis is greatly improved. This research provides an important theoretical support and technical guidance to construct new microwave driven hydrolysis with high efficiency in the future.
研究领域:
生物化学
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可再生能源
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产品关联
DOI
PubMed
高影响因子
RENEWABLE ENERGY
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2025
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IF 9.1
Deng Zhao,Tianyu Wu,Jiantao Wang,Shuo Ling,Huashan Wang,Hua Liu,Hui Liu,Shuai Guo,Xiudong Wei
Currently the thermal effect of light has received extensive attention in the field of concentrating solar power gasification, but the non-thermal effect of light has been neglected. In this study, a high-flux solar simulator was coupled with a thermogravimetric analyzer and the thermal effects of concentrating solar power were effectively controlled. The non-thermal effect of concentrating solar power on the gasification of char was studied for the first time. It was found that the non-thermal effect of concentrating solar power significantly reduced the gasification reaction temperature and activation energy of the samples. The reaction mechanism of non-thermal effect was proposed by analyzing the microstructure and chemical structure of the samples with equal conversion rate. The self-catalysis of graphite carbon under high radiation intensity promotes the pyrolysis of biomass carbon to form a highly active carbon chain structure to promote the gasification reaction. This study proves the importance of non-thermal effects in the field of concentrating solar power gasification research, and direct irradiation may have higher economic benefits than indirect irradiation. However, the quantitative description of this non-thermal effect needs further study.
研究领域:
能源科学
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材料科学
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产品关联
DOI
高影响因子
ACS Catalysis
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2021
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IF 13.084
Zhiqiang Rao,Yuehan Cao,Zeai Huang,Zihang Yin,Wenchao Wan,Minzhi Ma,Yanxin Wu,Junbu Wang,Guidong Yang,Yi Cui,Zhongmiao Gong,Ying Zhou
Photothermal catalysis, which couples both solar and thermal energies, has burgeoned as a promising approach to drive catalytic reactions. However, the utilization of light irradiation to tune the reaction paths to obtain ideal product distribution in photothermal catalysis is still of tremendous challenge. Herein, we successfully regulated the relationship between two core competition reactions through light irradiation during photothermal dry reforming of methane over Ni/Ga2O3, resulting in the promotion of H2 formation and the suppression of the reverse water gas shift reaction. The increase in the H2/CO ratio from 0.55 to 0.94 could be achieved. Furthermore, the combination of density functional calculations and X-ray photoelectron spectroscopy reveals that light irradiation impelled the direction of electron transfer to be reversed from Ga2O3 to Ni to form the Ni0 sites, which provides the generation of abundant hot electrons from the electronic interband transition of Ni to boost the formation and desorption of H2. This work promotes the understanding of nonthermal behaviors of light irradiation in light-driven photochemistry, which is significant for designing catalysts with high efficiency and controllable product distribution.
研究领域:
化学工程
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材料科学
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD HYDROCOLLOIDS
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2019
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IF 5.839
Dan-Dan Li,Na Yang,Yang Tao,En-Bo Xu,Zheng-Yu Jin,Yong-Bin Han,Xue-Ming Xu
The mechanism of induced electric field (IEF)-assisted acid hydrolysis was investigated by using guar gum, chitosan, and pectin as model polysaccharides . Roles of thermal and non-thermal effects were explored by temperature determination, HPSEC-MALLS-RI, SEM, FT-IR, XRD, and a rheometer. Results suggested that IEF affected the hydrolysis of polysaccharides by inducing thermal and non-thermal effects. Thermal effect contributed to the hydrolysis. As the excitation voltage increased, the thermal effect enhanced, with a temperature increased by about 25 °C after IEF (75 V) treatment for 4 h. Non-thermal effect, induced by the rapid and directional migration of charged species, varied with the electrical properties of the polysaccharides. It enhanced the hydrolysis of guar gum and pectin but negatively impacted the chitosan due to their different migration directions under IEF. IEF-assisted hydrolysis damaged the structural compactness of polysaccharides and significantly decreased the viscosity of their solutions. This study clarified the hydrolysis mechanism of polysaccharides under IEF, providing a theoretical guide for the application of IEF in the chemical modification of biopolymers.
研究领域:
食品科学
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化学工程
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生物技术
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
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2023
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IF 8.8
Ying Liu,Wenjuan Qu,Yuxuan Liu,Jamila A Tuly,Haile Ma
Food quality is greatly impacted by traditional heat methods for polygalacturonase (PG) inactivation; therefore, it's imperative to develop a novel infrared (IR) inactivation approach and identify its mechanism. Utilizing molecular dynamics (MD) simulation, this study verified the PG's activity, structure, active sites, and substrate channel under the single thermal and non-thermal effects of IR. PG activity was significantly reduced by IR, and structure was unfolded by increasing random coils (65.62 %) and decreasing β-sheets (29.11 %). MD data indicated that the relative locations of PG's active sites were altered by both IR effects, and the enzyme-substrate channel was shortened (10.53 % at 18 μm and 15.79 % at 80 °C). The thermal effect of IR on the inactivation of PG was significantly more pronounced than its non-thermal effect. This study unveiled the mechanism by which the infrared disrupted PG's activity, active sites, and substrate channels; thus, it expanded the infrared technique's efficacy in enzyme control.
研究领域:
食品科学
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生物物理学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Shiyu Zuo,Dongya Li,Haiming Xu,Dongsheng Xia
The Advanced Oxidation Processes (AOPs) still require further research in response to ever-increasing standard of reclaimed water reuse and operating environment requirements. In this study, an efficient microwave-ultraviolet catalyzed oxidation system (MW-UV) was successfully developed, and its degradation effect was studied by using activated H 2 O 2 , sodium percarbonate (SPC), persulfate (PS), and peroxymonosulfate (PMS) to degrade toxic organic contaminants in wastewater and actual industrial wastewater. It was shown that MW-UV had an exceptionally high capability to react with these four common peroxides to produce reactive radicals ( OH and SO 4 − ). This can destroy multiple toxic organic contaminants through nonselective oxidation with a wide range of pH applications, has strong adaptability to anions in bodies of water, and can effectively treat wastewater. The sequence of predominant free radical generation rate by MW-UV was SPC > H 2 O 2 > PS > PMS, with higher generation rate constant than other Fenton processes. The free radical evolution mechanisms for H 2 O 2 , SPC, PS, and PMS activation were also investigated. The thermal and non-thermal effects of microwave irradiation have a significant enhancement for UV reactions, and thus the synergy between the MW and UV can effectively activate peroxide. This treatment method could provide scientific basis and reference for degrading toxic organic contaminants in small-scale and limited space wastewater treatment.
研究领域:
环境工程
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化学工程
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水处理
✓ 已验证
DOI
高影响因子
TALANTA
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2024
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IF 5.6
Xiao Jia,Jingnan Ren,Zhifeng Zhang,Nawei Zhang,Qi An,Mingzhe Li,Siyi Pan,Gang Fan,Jinchu Yang,Yingjie Feng,Zongcan Yang,Yongming Xu
ABSTRACT The non-thermal and thermal effects on aroma of sea buckthorn juice have rarely been investigated. In this study, 57 odor compounds were identified in fresh sea buckthorn juice (FSBJ), high pressure processing sea buckthorn juice (HSBJ), and pasteurized sea buckthorn juice (PSBJ), including 29 esters, 8 aldehydes, 1 ketone, 5 alcohols, 5 acids, 6 terpenoids, and 3 others. Ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, ethyl hexanoate, and ethyl 2-hydroxy-3-methylbutanoate with flavor dilution factors ranging from 729 to 59049 contributed to the fruity odors of FSBJ and HSBJ. Besides, the formation of off-odor compounds including hexanal, nonanal, furfural, 3-methylbutanoic acid, and dimethyl disulfide with odor activity values ≥ 1, imparts fatty, roasted, sweaty, and cooked odor in PSBJ. The variations of vitamin C and reducing sugar are significantly associated with changes in odor-active compounds during pasteurized processing. These findings provide new insights that high pressure processing minimizes the adverse effects of pasteurization.
研究领域:
食品科学
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农业化学
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食品加工
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）