JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2022
·Vol. 331
·期 4
·1731-1740
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IF 1.754
Kubota Masahiko,Wu Hao,Kim Seong-Yun
A N’-N’ -di-n-hexyl-thiodiglycolamide and 2,2’-[(2-ethylhexyl)imino]bis[ N,N -bis(2-ethylhexyl)acetamide] impregnated porous silica-based adsorbent was prepared for enhancing the adsorption of palladium ions from simulated high-level liquid waste. The adsorbent exhibited a relatively fast palladium response and selectivity without the use of additional modification reagents. Palladium ions were adsorbed over a wide nitric acid range of 0.6−5 M and a broad temperature range of 288−323 K. The uniform distribution of adsorbed palldium ions onto the study adsorbent was confirmed by PIXE. Successful recovery of more than 90% of the palladium ions was achieved using 0.1 M thiourea via separation by column experiments. Based on the obtained data, it is expected that the prepared adsorbent can be used for the practical separation of palladium ions from high-level liquid waste.
研究领域:
化学工程
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核废物处理
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DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2021
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IF 3.178
Xiong Zheng,Yanqiong Bao,Dan Qu,Jing Wu,Guangzhao Qin,Yu Liu
With the key role of long-chain hydrocarbons in the wide applications in numerous industrial areas, such as working fluids, phase change materials, fuels, etc ., the knowledge of the thermal conductivity of hydrocarbons is essential in the energy conversion process. Thus, it is of great significance to get reliable experimental data of hydrocarbons’ thermal conductivity for further accurately theoretical predictions and the potential applications. In this work, the thermal conductivities of two long-chain hydrocarbons of n-dodecane and n-tetradecane, are investigated experimentally. The transient hot-wire method was used for the measurement of the thermal conductivity under the conditions of 293–523 K and 0.1–15.0 MPa. By comparing the present work with literature results, the possible reasons for the deviations were analyzed. The results in this study provide accurately measured of the thermal conductivity of the two long-chain hydrocarbons at high temperature and pressure, which are expected to fill the gap in literature.
研究领域:
化学工程
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能源科学
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DOI
高影响因子
JOURNAL OF CHEMICAL RESEARCH
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2016
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IF 0.661
Zhengyi Li,Yuan Chen,Yue Yin,Zhiming Wang,Xiaoqiang Sun
A simple and convenient two-step method has been developed and used to synthesise 25 (4 of which are novel) unsymmetrical N,N′-disubstituted thioureas in water. Alkylamines or variously substituted arylamines reacted smoothly with phenyl chlorothionoformate at room temperature to form thiocarbamates, which were then reacted with another alkyl- or arylamine in water at reflux to afford the unsymmetrical N,N′-disubstituted thioureas in good to excellent yields. Mild conditions, simple work-up, high yields as well as using water as solvent are the major advantages of the method.
研究领域:
有机化学
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绿色化学
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DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2021
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IF 5.541
Zhen-Guo Fan,Zhen-Yu Tian,Wang Li,Zhi-Hao Zheng,Jiu-Zhong Yang
N, N-dimethylformamide (DMF) is a kind of general solvent in Li-ion industry and nitrogen-containing component of amines fuels. The trace vapor of DMF is very harmful to human and environment, which could be treated by pyrolysis. The pyrolysis of DMF was newly carried out in a flow reactor at 30 Torr within 873–1273 K. Synchrotron radiation single photoionization coupled with molecular beam mass spectrometry was employed to detect the reactants, intermediates and products. 26 species were identified and quantified. Products related to NOx, such as nitrosomethane, nitrosyl cyanide and N-methylformamide were identified. With the temperature increasing, the mole fractions of species tend to increase monotonically, while nitrosyl cyanide, ethyl radical, cyclopropane , carbon monoxide , ethanol, acetaldehyde and ethanol exhibit peak-shaped curves. Hydrogen abstractions and dissociations are the main initial pathways of DMF consumption. As the main hydrocarbon products, methane and ethylene are predominantly formed by the H abstraction reaction by methyl radical and the β-scission of ethyl radical, respectively. Carbon monoxide is mainly generated from the dissociation of DMF and its mole fraction is at the same level as the fuel DMF. HCN is the most abundant product among all the carbonitride species via H abstraction of CH 2 =NH as well as the collisions of CN with alkanes and aldehydes. These results provide a theoretical basis for further study of treating DMF in the exhaust fumes through pyrolysis and have reference value for the clean utilization of amine fuels.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
FLUID PHASE EQUILIBRIA
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2021
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IF 2.775
Xiong Zheng,Dan Qu,Fa Zhang,Yu Liu,Guangzhao Qin
Hydrocarbons play an important role in lots of industrial processes. Thermal conductivity is an important thermophysical property of fluids in energy conversion process, such as the design of the heat transfer system and the evaluation of thermodynamic cycle. Thus, it is of great significance to acquire solid experimental data and develop reliable models for achieving accurate thermal conductivity of hydrocarbons. In this work, thermal conductivity of two common fuels, n-octane and n-decane, were studied by combining experimental and theoretical methods. Using the transient hot wire method, the thermal conductivity is measured with temperature ranging from 303 to 523 K and pressures ranging from 0.1 to 15 MPa. Excellent agreement is achieved by comparing our experimental results with literatures. Furthermore, the mechanism for the influence of temperature and pressure on thermal conductivity of liquid n-octane and n-decane was explored preliminarily based on Bridgman's theory. In addition, we proposed a modified model considering the critical thermal conductivity enhancement, with which the average absolute deviations are 0.49% and 0.43% for n-octane and n-decane, respectively. It is shown that our proposed model has better predictive ability for representing thermal conductivity than the four traditional theoretical models (Assael model, Sun and Teja model, Huber and Perkins model, Liu model), especially at the vicinity of the critical point. The achievements in the present study are not only useful for relevant industrial application but also helpful for understanding the thermal conductivity critical enhancement when approaching the liquid-gas critical point for n-alkanes.
研究领域:
化学工程
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热物理
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DOI
高影响因子
TETRAHEDRON
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2020
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IF 2.233
Zhen-Hua Li,Xiao-Meng Sun,Jin-Jing Qin,Zhi-Yong Tan,Wen-Biao Wang,Yao Ma
An efficient and divergent synthesis of N -arylbenzimidazoles and N -arylindazoles from arylamino oximes based on reaction conditions selection was developed. The synthesis was approached by treating oximes with BTC and the chemoselectivity was regulated by the amount of Et 3 N. This switchable N–N and N–C bond formation process features mild reaction conditions, simple execution, high chemoselectivity and broad substrate scope.
研究领域:
有机化学
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合成化学
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DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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2019
·Vol. 85
·期 12
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IF 4.077
Xinyu Lu,Weiwei Wang,Lige Zhang,Haiyang Hu,Ping Xu,Tao Wei,Hongzhi Tang
N,N-Dimethylformamide (DMF) is one of the most common xenobiotic chemicals, and it can be easily emitted into the environment, where it causes harm to human beings. Herein, an efficient DMF-degrading strain, DM1, was isolated and identified as Methylobacterium sp. This strain can use DMF as the sole source of carbon and nitrogen. Whole-genome sequencing of strain DM1 revealed that it has a 5.66-Mbp chromosome and a 200-kbp megaplasmid. The plasmid pLVM1 specifically harbors the genes essential for the initial steps of DMF degradation, and the chromosome carries the genes facilitating subsequent methylotrophic metabolism. Through analysis of the transcriptome sequencing data, the complete mineralization pathway and redundant gene clusters of DMF degradation were elucidated. The dimethylformamidase (DMFase) gene was heterologously expressed, and DMFase was purified and characterized. Plasmid pLVM1 is catabolically crucial for DMF utilization, as evidenced by the phenotype identification of the plasmid-free strain. This study systematically elucidates the molecular mechanisms of DMF degradation by Methylobacterium.IMPORTANCE DMF is a hazardous pollutant that has been used in the chemical industry, pharmaceutical manufacturing, and agriculture. Biodegradation as a method for removing DMF has received increasing attention. Here, we identified an efficient DMF degrader, Methylobacterium sp. strain DM1, and characterized the complete DMF mineralization pathway and enzymatic properties of DMFase in this strain. This study provides insights into the molecular mechanisms and evolutionary advantage of DMF degradation facilitated by plasmid pLVM1 and redundant genes in strain DM1, suggesting the emergence of new ecotypes of Methylobacterium.
研究领域:
环境微生物学
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生物化学
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DOI
高影响因子
Biotechnology for Biofuels
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2019
·Vol. 12
·期 1
·1-17
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IF 5.452
Chen Yumeng,Wu Chuan,Shen Yaling,Ma Yushu,Wei Dongzhi,Wang Wei
Background The filamentous fungus Trichoderma reesei produces cellulase enzymes that are widely studied for lignocellulose bioconversion to biofuel. N,N-dimethylformamide (DMF) is a versatile organic solvent used in large quantities in industries.Results In this study, we serendipitously found that biologically relevant concentrations of extracellular DMF-induced cellulase production in the T. reesei hyper-cellulolytic mutant Rut-C30 and wild-type strain QM6a. Next, by transcriptome analysis, we determined that plc-e encoding phospholipase C was activated by DMF and revealed that cytosolic Ca2+ plays a vital role in the response of T. reesei to DMF. Using EGTA (a putative extracellular Ca2+ chelator) and LaCl3 (a plasma membrane Ca2+ channel blocker), we demonstrated that DMF induced a cytosolic Ca2+ burst via extracellular Ca2+ and Ca2+ channels in T. reesei, and that the cytosolic Ca2+ burst induced by DMF-mediated overexpression of cellulase through calcium signaling. Deletion of crz1 confirmed that calcium signaling plays a dominant role in DMF-induced cellulase production. Additionally, 0.5–2% DMF increases the permeability of T. reesei mycelia for cellulase release. Simultaneous supplementation with 1% DMF and 10 mM Mn2+ to T. reesei Rut-C30 increased cellulase activity approximately fourfold compared to that without treatment and was also more than that observed in response to either treatment alone.Conclusion sOur results reveal that DMF-induced cellulase production via calcium signaling and permeabilization. Our results also provide insight into the role of calcium signaling in enzyme production for enhanced cellulase production and the development of novel inducers of cellulase.
研究领域:
生物化学
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微生物学
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工业酶学
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产品关联
DOI
PubMed
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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2020
·Vol. 86
·期 17
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IF 4.016
Ting Yang,Ya-Hui Shao,Li-Zhong Guo,Xiang-Lin Meng,Hao Yu,Wei-Dong Lu
Chromohalobacter salexigens DSM 3043 can grow on N,N-dimethylglycine (DMG) as the sole C, N, and energy source and utilize sarcosine as the sole N source under aerobic conditions. However, little is known about the genes and enzymes involved in the conversion of DMG to sarcosine in this strain. In the present study, gene disruption and complementation assays indicated that the csal_0990, csal_0991, csal_0992, and csal_0993 genes are responsible for DMG degradation to sarcosine. The csal_0990 gene heterologously expressed in Escherichia coli was proven to encode an unusual DMG dehydrogenase (DMGDH). The enzyme, existing as a monomer of 79 kDa with a noncovalently bound flavin adenine dinucleotide, utilized both DMG and sarcosine as substrates and exhibited dual coenzyme specificity, preferring NAD+ to NADP+. The optimum pH and temperature of enzyme activity were determined to be 7.0 and 60°C, respectively. Kinetic parameters of the enzyme toward its substrates were determined accordingly. Under high-salinity conditions, the presence of DMG inhibited growth of the wild type and induced the production and accumulation of trehalose and glucosylglycerate intracellularly. Moreover, exogenous addition of DMG significantly improved the growth rates of the four DMG– mutants (Δcsal_0990, Δcsal_0991, Δcsal_0992, and Δcsal_0993) incubated at 37°C in S-M63 synthetic medium with sarcosine as the sole N source. 13C nuclear magnetic resonance (13C-NMR) experiments revealed that not only ectoine, glutamate, and N-acetyl-2,4-diaminobutyrate but also glycine betaine (GB), DMG, sarcosine, trehalose, and glucosylglycerate are accumulated intracellularly in the four mutants.IMPORTANCE Although N,N-dimethylglycine (DMG) dehydrogenase (DMGDH) activity was detected in cell extracts of microorganisms, the genes encoding microbial DMGDHs have not been determined until now. In addition, to our knowledge, the physiological role of DMG in moderate halophiles has never been investigated. In this study, we identified the genes involved in DMG degradation to sarcosine, characterized an unusual DMGDH, and investigated the role of DMG in Chromohalobacter salexigens DSM 3043 and its mutants. Our results suggested that the conversion of DMG to sarcosine is accompanied by intramolecular delivery of electrons in DMGDH and intermolecular electron transfer between DMGDH and other electron acceptors. Moreover, an unidentified methyltransferase catalyzing the production of glycine betaine (GB) from DMG but sharing no homology with the reported sarcosine DMG methyltransferases was predicted to be present in the cells. The results of this study expand our understanding of the physiological role of DMG and its catabolism to sarcosine in C. salexigens.
研究领域:
微生物学
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2021
·Vol. 331
·期 1
·241-247
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IF 1.371
Wang J. H.,Zhao X. Y.,Shi Y.,Wan Y.,Fu H. Y.,Zheng W. F.
The reaction mechanisms and rate constants of N, N-diethylhydroxylamine (DEHA) with · OH, CO 3 − · , e aq − and · H were studied. Results show that · OH radicals oxidize DEHA by hydrogen abstraction from DEHA’s hydroxyl group to form transient (C 2 H 5 ) 2 NO · , which has an absorption maximum at 395 nm. The transient intermediates for the reactions of DEHA with CO 3 − · and e aq − , as well as protonated DEHA with · H, show no absorption peak between 300 and 800 nm. The rate constants for the reactions of DEHA with · OH, CO 3 − · and e aq − , also protonated DEHA with · H, were measured.
研究领域:
放射化学
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自由基化学
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DOI
高影响因子
ChemCatChem
·
2019
·Vol. 11
·期 16
·3919-3926
·
IF 4.495
Ke Liu,Zhenbo Zhao,Weiwei Lin,Qiang Liu,Qifan Wu,Ruhui Shi,Chao Zhang,Haiyang Cheng,Masahiko Arai,Fengyu Zhao
Graphical Another drop of copper : A non-noble metal catalyst of Cu/TiO 2 is effective for the heterogeneous N -methylation of N -methylaniline with CO 2 and H 2 , in which CHO* is formed as methyl reagent, and it reacts with N -methylaniline to produce intermediate N -methylformanilide followed by its hydrogenation to N,N -dimethylaniline. A non-noble heterogeneous catalyst of Cu/TiO 2 was prepared for N -methylation of N -methylaniline (MA) with CO 2 and H 2 . 5 wt.–% Cu loaded TiO 2 (P25) catalyst exhibited a high performance, with 82 % MA conversion and 98 % N,N -dimethylaniline (DMA) selectivity under the reaction conditions used (4 MPa H 2 , 2 MPa CO 2 , 180 °C, 36 h). The Cu/TiO 2 catalyst was more effective with respective to the total conversion and the DMA selectivity as compared to 5 wt.–% Cu loaded catalysts on CeO 2 , ZnO and activated carbon materials. The possible active species of Cu/TiO 2 catalyst should be both Cu + and Cu 0 which contributed to the high activity as the reaction conversion increased linearly with them exposed on the surface of catalyst. Moreover, the reaction pathways involved were studied; it was likely that the reaction took place via an intermediate of formaldehyde that was formed from CO 2 and H 2 , as confirmed by in situ diffuse reflectance Fourier-transform infrared spectroscopy, then it reacted with MA to give N -methylformanilide (MFA), and finally MFA was hydrogenated to DMA.
研究领域:
催化化学
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环境化学
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DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2023
·
IF 2.6
Shuo Yuan,Yi Liu,Jingwei Cui,Xiong Zheng
Hydrocarbons have wide applications in various industrial processes, and the knowledge of thermophysical properties is the foundation for their utilization. As an important thermophysical property, the thermal conductivity of fluids is vital in the evaluation of energy conversion quality, like heat transfer enhancement , thermodynamic cycle efficiency evaluation, etc. Therefore, obtaining accurate experimental data is of great importance for the utilization of hydrocarbons. Here, the thermal conductivities of liquid n-nonane and n-undecane were investigated using the transient hot-wire method (combined expanded uncertainty is 2.0 %) with a wide temperature and pressure range from 293.15 to 523.15 K and 0.1 to 15.0 MPa. For the convenience of engineering applications, a polynomial as a function of temperature and pressure was proposed to correlate the experimental data, the average absolute deviations between experimental data and fitted data are 0.29 % for n-nonane and 0.35 % for n-undecane, which indicates that the polynomial describes the experimental data well in the measured region. Meanwhile, the available literary data were collected and compared with our results, and good agreement was found between literary data and our results. This work is not only helpful for the industrial applications of hydrocarbons but also helps to understand the internal mechanism of the thermal conductivity of hydrocarbons.
研究领域:
化学工程
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热物理
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）