INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Muyuan Chai,Wenbo Zhao,Genming Li,Shengchao Xu,Qingming Jia,Yuan Chen
In order to avoid the high energy consumption in SO2 capture with aqueous amine absorbents, a liquid–liquid SO2 phase-change absorbent (SPCA) was developed in the present work using N,N-dimethylaniline (DMA) as absorbent, and high-boiling liquid paraffin was used as solvent to adjust the boiling point of the solution. The homogeneous solution would form two immiscible liquid phases after SO2 bubbling, only the SO2-rich phase needed to be desorbed, which could effectively reduce the energy consumption. Different from the liquid–solid phase-change absorbents developed in our previous work, the liquid–liquid phase-change absorbent avoid their shortcomings such as difficulties in separation of absorption products. The absorption product of SPCA was proved to be a charge-transfer complex DMA·SO2 by NMR and FTIR characterization, and the phase-change mechanism was attributed to the polarity variation between DMA and DMA·SO2. The viscosities of SPCAs was lower than 11.65 mPa·s, and the viscosity of SO2-rich phase was 3.9 mPa·s at 30 °C. The mass absorption capacity was found to be 0.89 g SO2/g DMA at 1 atm and 20 °C by ignoring liquid paraffin. The SPCA exhibited extremely high mass selectivity of SO2/CO2 with the value of 351. In addition, it was found that water had no effect on the structure of the absorption product and the SO2 capacity of SPCA. SPCA could be completely regenerated in 50 min at 80 °C. All the results showed that the SPCAs composed of DMA/liquid paraffin have a good application prospect.
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RSC Advances
·
2013
·Vol. 3
·期 43
·20877-20882
·
IF 2.562
Changqing Liu,Guoxin Hu
Supercritical fluid exfoliation of layered titanate is an efficient way to prepare titania nanosheets. However, a phase transition may occur under high temperature and high pressure conditions. We have studied the phase transition process of H1.07Ti1.73O4·H2O in two solvents (N,N-dimethylformamide (DMF) and water) under supercritical conditions by XRD measurements. Experimental results show that exfoliation is found in supercritical DMF, while in supercritical water exfoliation and the phase transition occur concurrently, transforming it into anatase. An interpretation of the phase transition is proposed: as water is a protic solvent, it can supply H+ under high temperature and high pressure conditions; the phase transition is caused by dissolution and recrystallization, which is confirmed by XRD and SEM results. The suitable solvents shall be selected for the preparation of titania nanosheets by supercritical exfoliation.
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JOURNAL OF SURFACTANTS AND DETERGENTS
·
2015
·Vol. 18
·期 5
·739-746
·
IF 1.685
Zhihu Yan,Caili Dai,Mingwei Zhao,Guang Zhao,Yuyang Li,Xuepeng Wu,Yifei Liu,Mingyong Du
A noncovalent bonding method was utilized for forming multiresponsive surface-active ionic liquids in mixed N -alkyl- N -methylpiperidinium bromide (C 16 MDB) and potassium phthalic acid (PPA). Rheology, cryogenic-transmission electron microscopy, dynamic light scattering and nuclear magnetic resonance were used to investigate the aggregation property of surface-active ionic liquids in aqueous solution. The efficiency of the shielding effect in the form of hydrophobic effects and electrostatic attraction between PPA and the C 16 MDB headgroup under diverse pH conditions is found to be the root cause of a shift in the aggregate's morphological transformation. In addition, the molecular motion of surfactant molecules becomes more active as the temperature increase provides the property of thermoresponsive to the surface-active ionic liquid system.
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Journal of the American Chemical Society
·
2024
·
IF 14.4
Weihang Li,Haoyang Jiang,Xiang Zhang,Bo Lei,Le Li,Haoshen Zhou,Miao Zhong
Electrified synthesis of high-value organonitrogen chemicals from low-cost carbon- and nitrogen-based feedstocks offers an economically and environmentally appealing alternative to traditional thermocatalytic methods. However, the intricate electrochemical reactions at electrode surfaces pose significant challenges in controlling selectivity and activity, especially for producing complex substances such as N,N-dimethylformamide (DMF). Herein, we tackle this challenge by developing relay catalysis for efficient DMF production using a composite WO2–NiOOH/Ni catalyst with two distinctive active sites. Specifically, WO2 selectively promotes dimethylamine (DMA) electrooxidation to produce strongly surface-bound (CH3)2N*, while nearby NiOOH facilitates methanol electrooxidation to yield more weakly bound *CHO. The disparity in binding energetics of the key C- and N-intermediates expedites C–N coupling at the WO2–NiOOH interface. In situ infrared spectroscopy with isotope-labeling experiments, quasi-in situ electron paramagnetic resonance trapping experiments, and electrochemical operating experiments revealed the C–N coupling mechanism and enhanced DMF-synthesis selectivity and activity. In situ X-ray absorption spectroscopy (XAS) and postreaction transmission electron microscopy (TEM) studies verified the stability of WO2–NiOOH/Ni during extended electrochemical operation. A Faradaic efficiency of ∼50% and a production rate of 438 μmol cm–2 h–1 were achieved at an industrially relevant current density of 100 mA cm–2 over an 80 h DMF production period. This study introduces a new paradigm for developing electrothermo relay catalysis for the sustainable and efficient synthesis of valuable organic chemicals with industrial potential.
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PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2025
·
IF 3.3
Zhao Shanshan,Du Shouwen,Guan Yudong,Schlüter Hartmut
The structural instability and electronegativity of sialic acids make N-sialoglycan profiling challenging. We compared commonly used preparation strategies, including native, acetohydrazide-based derivatization, and permethylation, in N-glycomics with nMatch, an R-based bioinformatics tool that ensures full coverage of the detected N-glycans using mass spectrometry. We demonstrated that permethylation leads to efficient detection of not only N-sialoglycans but also other N-glycans and, therefore, provides a valuable reference for the selection of the appropriate N-glycan preparation strategy in future studies.
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PubMed
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EUROPEAN POLYMER JOURNAL
·
2025
·
IF 6.3
Qing Gao,Hailin Fu,Hui Liu,Pengfei Li,Jin Shi,Yao Lin,Ziyuan Song
Poly(sarcosine) (PSar)-based diblock copolypeptoid nanoparticles are promising alternatives to PEGylated polymeric nanocarriers. However, their preparation was limited by the slow polymerization kinetics and low assembly concentrations. Herein, we report the facile preparation of copolypeptoid nanoparticles through polymerization-induced self-assembly of N -substituted glycine N -carboxyanhydrides (NNCAs) in solvents with low polarity and weak hydrogen-bonding ability like dichloromethane (DCM). In contrast to the conventional polymerization in N , N -dimethylformamide (DMF), NNCAs were polymerized at an accelerated rate in DCM that minimized side reactions from water and other impurities. With isopentylamine-initiated PSar as the first stabilizing block, the polymerization of N -benzyl glycine N -carboxyanhydrides resulted in the formation of spherical or rod-like nano-assemblies at high solid contents (up to 15%) within several hours. We believe this work not only improves our basic understanding on NNCA polymerization behaviours, but also offers an efficient strategy to prepare drug nanocarriers with PSar corona, facilitating the downstream application studies.
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Asian Journal of Organic Chemistry
·
2020
·Vol. 9
·期 7
·1076-1080
·
IF 3.13
Siyu Wu,Gengwen Yin,Caihong Cheng,Bo Liang,Haiquan Zhang
Graphical A new product -PDMBPRI-4F was synthesized by one-step method, which has the special property of fluorescence quenching caused by intramolecular charge transfer. Nucleophilic substitution process with loss of one fluorine atom was observed when pentafluorophenyl substituted benzo[ghi]perylene triimide and perylene diimide were heated in N , N -dimethylformamide, in which N , N -dimethylformamide acted both as solvent and nucleophile reagent. Unexpectedly, the obtained product exhibited significant intramolecular charge transfer optical properties in solutions. The mechanism of nucleophilic substitution and the influence of substituent were further studied and proposed in this manuscript.
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Protection of Metals and Physical Chemistry of Surfaces
·
2020
·Vol. 56
·期 4
·740-745
·
IF 0.985
Lijun Chen,Chen Xiaolong,Gong Yilu,Shao Tantan,Zhang Xin,Chen Dawei,Cai Zhibin
Abstract Polyacrylate latex contained monobutyl itaconate (MBI) and N,N-diethylacrylamide (DEA) was successfully prepared by semi-continuous seeded emulsion polymerization with a green mixed emulsifier of sodium dodecyl benzene sulfonate (SDBS) anion surfactant and tetradecyl hydroxypropyl decyl betaine (THDB) amphoteric emulsifier, the mixed monomers of methyl methacrylate (MMA), butyl acrylate (BA) were modified by MBI and DEA, which were initiated with potassium persulfate (KPS). The structure was characterized by Fourier transform infrared spectroscopy (FTIR). The film of latex was measured by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA). The particle size of the latex was tested by Zetatrac dynamic light scattering detector. The optimal conditions are as follows: the amount of mixed emulsifiers is 6.0%; the optimum mass ratio of SDBS to THDB is 1 : 1; the amount of initiator is 0.7%; the mass rate of main monomers of MMA : BA = 1 : 1; the amount of DEA is 5.0% and MBI is 2%. In this paper, the polyarcylate emulsion shows excellent thermal stability and hydrophobicity.
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Journal of Oncology
·
2022
·
IF 4.501
Sheng-Xiong Zhang,Wen Tian,Yuan-Liang Liu,Jia-Hui Ni,Dan Zhang,Hua-Feng Pan,Zi-Ming Zhao,Bo Ai,Zhe-Sheng Chen,Li-Zhu Lin,Wei Liu
Early diagnosis and treatment of gastric precancerous lesions (GPL) are key factors for reducing the incidence and morbidity of gastric cancer. The study is aimed at examining GPL in mice induced by N-methyl-N-nitroso-urea (MNU) and to illustrate the underlying mechanisms of tumorigenesis. In this study, we utilized an in vivo MNU-induced GPL mouse model, and histopathological changes of the gastric mucosa were observed by hematoxylin and eosin (H&E-stain) and alcian blue (AB-PAS-stain). The level of miR-194-5p in the gastric mucosa was determined by real-time polymerase chain reaction. We used transmission electron microscopy to observe the effects of MNU on gastric chief cells and parietal cells. We performed immunohistochemical detection of HIF-1α, vWF, Ki-67, and P53, while the changes in the protein expression of key genes in LKB1-AMPK and AKT-FoxO3 signaling pathways were detected by western blot analysis. We demonstrated that the miR-194-5p expression was upregulated under hypoxia in GPL gastric tissues, and that a high miR-194-5p expression level closely related with tumorigenesis. Mechanistically, miR-194-5p exerted the acceleration of activities related to metabolic reprogramming through LKB1-AMPK and AKT-FoxO3 pathways. Furthermore, similar to miR-194-5p, high expression levels of AMPK and AKT were also related to the metabolic reprogramming of GPL. Moreover, we revealed the correlation between the expression levels of miR-194-5p, p-AMPKα, p-AKT, and FoxO3a. These findings suggest that miR-194-5p/FoxO3 pathway is important for the reversal of metabolic reprogramming in GPL. Thus, exploring strategies to regulate the miR-194-5p/FoxO3a pathway may provide an efficient strategy for the prevention and treatment of GPL.
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PubMed
高影响因子
THERMOCHIMICA ACTA
·
2021
·
IF 3.115
Fenhong Song,Qingli Wang,Qinglong Meng,Han Mu,Jing Fan
Recently, biodiesel has received tremendous attention from a lot of scientists as a biodegradable, renewable and high-potential fuel which could be used directly or blended with diesel in internal combustion engines. The adequate thermophysics properties of fuel are required to model the process of fuel spray, atomization and combustion accurately. In this work, three fuel blends containing methyl laurate and n-undecane, n-dodecane, n-tridecane were prepared and an important transport property—liquid thermal conductivity of which were measured by the transient hot wire method system. The measurement was conducted at temperature ranging from 292 K to 362 K at atmospheric pressure with the mass fraction of methyl laurate being nearly 0.2000, 0.4000, 0.6000 and 0.8000 (by weight) in the binary mixtures. Furthermore, the relationship between the experimental results and temperature and concentration of methyl laurate were correlated as a function. The uncertainty of the experimental system is less than ±2.0%.
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FLUID PHASE EQUILIBRIA
·
2015
·
IF 2.2
Xiaofei Yan,Danxing Zheng,Min Zhang,Wenzhi Yang
To develop novel working pairs for absorption power cycles, this study selected 1,1,1,3,3,3-hexafluoropropane (HFC236fa) + N , N -dimethylformamide (DMF) and HFC236fa + N -methyl-2-pyrrolidone (NMP) systems. In addition, the vapor–liquid equilibrium (VLE) data of the two systems were measured in a temperature range extending from 293.15 K to 353.15 K and a pressure range of 30–900 kPa. The five-parameter non-random two liquid (NRTL) model was chosen to regress the obtained VLE data. The results indicated that the NRTL model was suitable for the regression of the VLE data, and the maximum deviations of the pressure between the experimental and calculated values were 4.06% and 3.83%, and the average relative deviations were 1.55% and 1.90%, respectively. The regressed activity coefficients were both less than 1, which indicated that the two binary mixtures exhibit negative deviations from Raoult’s law. Therefore, the two systems exhibit good affinity. However, the activity coefficient of HFC236fa + DMF is smaller than that of HFC236fa + NMP. Finally, the systems in the literature were compared to this work, and the affinity of the systems was analyzed based on the molecular structure and hydrogen bond .
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JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2018
·
IF 2.196
Jian Yang,Xianyang Meng,Jiangtao Wu
As the important industrial raw materials, n-pentene, n-hexene, and n-heptene are widely used as gasoline additives to improve the combustion characteristics of gasoline and polymerized monomer to synthesize many important polymer compounds. Therefore, reliable density data are significant for these fluids to apply in industry. In this work, new experimental densities of n-pentene, n-hexene, and n-heptene have been measured at pressures up to 100 MPa along nine isotherms between 283 and 363 K by using a high pressure vibrating-tube densimeter. The experimental system was calibrated using water and a vacuum and was tested with R134a over the entire temperature and pressure ranges. The combined expanded uncertainties of the temperature, pressure, and density with a level of confidence of 0.95 (k = 2) are estimated to be 16 mK, 0.062 MPa (p ≤ 60 MPa), 0.192 MPa (60 MPa < p < 100 MPa), and up to 0.6 kg·m–3 depending on the temperature and pressure ranges. The density data were correlated with the Tait-like equation, and the average absolute deviations are 0.06, 0.04, and 0.05%. Furthermore, the isothermal compressibility and the isobaric thermal expansivity were derived from the Tait-like equation over the experimental temperature and pressure ranges.
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危险品化学品经营许可证（带存储）