ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Chunguang Chen,Liangyu Li,Junming Su,Congcong Zhang,Xiang Chen,Tao Huang,Aishui Yu
Although dimethylsulfoxide (DMSO) solvent has been widely researched in rechargeable lithium-oxygen (Li-O 2 ) batteries , high polarization voltage and low rate capability limited its application. In this work, we reported a DMSO-based electrolyte system by adding N, N-dimethylacetamide (DMA) to adjust its physical and electrochemical properties. The ionic conductivity , viscosity, oxygen solubility and diffusion coefficient of the mixed electrolytes as well as their electrochemical performance in Li-O 2 batteries are researched. The electrochemical tests show that the optimized DMSO/DMA volume ratio is 30 to 70 based on the rate performance and polarization voltage of the cell. Compared with that of the pure DMSO-based electrolyte, the cell with the mixed electrolyte shows improved rate capability and reduced charge-discharge over-potential. When increasing current density from 0.2 to 0.5 mA cm −2 , the capability retention improves from 32% to 59%. Meanwhile, the charge-discharge voltage gap drops from 1.4V to 0.9V at a current density of 0.2 mA cm −2 . The improved electrochemical performance could be attributed to low viscosity, high oxygen solubility and diffusion coefficient as well as the low charge-transfer resistance with the mixed electrolyte.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
International Journal of Environmental Research and Public Health
·
2016
·Vol. 13
·期 9
·925
·
IF 2.035
Hong-Qin Sun,Yang Du,Zi-Yang Zhang,Wen-Jing Jiang,Yan-Min Guo,Xi-Wu Lu,Yi-Min Zhang,Li-Wei Sun
Benzophenone (BP) andN,N-diethyl-3-methylbenzamide (DEET) are two chemicals often used in personal care products (PCPs). There is a lack of systematic ecotoxicological evaluations about the two chemicals to aquatic organisms. In the present study, the acute toxic effects onChlorella vulgaris,Daphnia Magana, andBrachydanio reriowere tested and the ecotoxicological risks were evaluated. For BP, the 96-h half-maximal effective concentration (EC50) onC. vulgariswas 6.86 mg/L; the 24-h median lethal concentration (LC50) onD. maganawas 7.63 mg/L; the 96-h LC50onB. reriowas 14.73 mg/L. For DEET, those were 270.72 mg/L, 40.74 mg/L, and 109.67 mg/L, respectively. The mixture toxicity of BP and DEET, onC. vulgaris,D. magana, andB. rerioall showed an additive effect. The induced predicted no-effect concentrations (PNECs) for BP and DEET by assessment factor (AF) method are 0.003 mg/L and 0.407 mg/L, respectively. Both are lower than the concentrations detected from environment at present, verifying that BP and DEET are low-risk chemicals to the environment.
研究领域:
环境科学
·
毒理学
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DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2012
·
IF 1.693
Yabo Hao,Songhong Zhang,Kejian Yao
Vapor–liquid equilibrium (VLE) data for methanol + tert-butylamine + N,N-dimethylformamide (DMF) and constituent binary systems containing tert-butylamine at 101.3 kPa were measured. A maximum boiling point azeotrope was observed at the methanol mole fraction of 0.763, corresponding to the temperature of 340.28 K for the binary system methanol + tert-butylamine. The binary equilibrium data were correlated using Wilson, nonrandom two-liquid (NRTL), and universal quasichemical activity coefficient (UNIQUAC) models, respectively. The VLE data of the ternary system were calculated with the binary interaction parameters of the NRTL model, and the average absolute deviations of the equilibrium temperature and the vapor-phase mole fractions for methanol and tert-butylamine were about 0.87 K, 0.014, and 0.018, respectively. The results show that DMF can break the azeotrope of the methanol + tert-butylamine system as a solvent.
研究领域:
化学工程
·
物理化学
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Jennifer Runhong Du,Faxin Du,Kang Yang,Jingfeng Zheng,Kailai Ma,Chunliang Du,Hanjun Yang
Poly(N,N-dimethylaminoethyl methacrylate) (PDM) is a water-soluble polymer that can be crosslinked via a quaternization reaction that takes 4–20 h. Polyhalogenated hydrocarbons with different structures were screened to identify high-efficiency crosslinking agents for PDM. For this purpose, the gelation time of bulk crosslinked PDM and the separation performance of interfacially crosslinked PDM membranes were investigated. Use of bromohydrocarbons with benzylic and allylic types and high functional group density can afford the rapid quaternization reaction of PDM. PDM nanofiltration membranes were prepared via interfacially crosslinking PDM with 1,3,5-tris(bromomethyl)benzene (TBB), and the effects of membrane preparation conditions (including PDM concentration, coating time, TBB concentration, and crosslinking time) on the permeation and separation performances of as-prepared membranes were investigated. The PDM membrane prepared at a PDM concentration of 6 g/L, TBB concentration of 40 mmol/L, coating time of 30 s, and crosslinking time of 30 s exhibited a water flux of 20.3 L/(m 2 ·h) and a salt rejection of 90%, when the membrane was treated with a 1000 mg/L MgSO 4 aqueous solution at 0.8 MPa pressure. The PDM membrane was positively charged and the extent of salt rejection followed the order MgCl 2 > NaCl ≈ MgSO 4 > Na 2 SO 4 . The membrane also exhibited good antifouling properties and chlorine resistance.
研究领域:
材料科学
·
环境工程
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产品关联
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2024
·
IF 2.8
Tao Jia,Weixue Jiang,Jia Yu
The compressed liquid densities of n -pentane(1) + n -dodecane(2) binary mixtures were measured using a high pressure vibrating-tube densimeter at temperatures from 283 K to 363 K, pressures up to 100 MPa, and five different compositions ( x 1 = 0.3778, 0.6230, 0.7968, 0.9051, and 1). The densities of binary mixtures were correlated using the modified Tait equation, and the absolute average deviations of the experimental and calculated values were 0.010 %, 0.019 %, 0.016 %, 0.025 %, and 0.017 %, respectively. In addition, the isothermal compressibility and the isobaric thermal expansivity were calculated from the obtained densities.
研究领域:
物理化学
·
热力学
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 12
·1-9
·
IF 5.479
Zhang Cong,Liu Di,Zhang Han,Tan Xingrong,Chen Shihong
A ratiometric electrochemiluminescent (ECL) assay is described for the determination of the calcium(II) regulator calcitonin (CT). The method is making use of (a) graphite-like carbon nitride (g-C 3 N 4 ) as the cathodic luminophore, (b) N-(aminobutyl)-N-(ethylisoluminol) (ABEI) as the anodic luminophore, and (c) peroxodisulfate and dissolved oxygen as coreactants. The luminous potential of g-C 3 N 4 and ABEI can be well distinguished because of their different luminescent properties. Energy transfer between g-C 3 N 4 and ABEI is not observed, and the coreactants peroxodisulate and oxygen do not interfere with each other. Au nanoparticles were functionalized with g-C 3 N 4 and placed on the electrode to serve as a matrix for immobilization of primary antibody (Ab 1 ). In the presence of CT, it will bind to the electrode. Then secondary antibody (Ab 2 ) modified with polyaniline (PANI) and ABEI is incubated onto the electrode. With the increase in the concentration of CT, the blue ECL of g-C 3 N 4 is quenched by PANI, while the blue luminescence of ABEI is enhanced. This enables ratiometric detection of calcitonin by ratioing the internsities at 460 and 475 nm. Response is linear in the 0.1~40 pg·mL −1 CT concentration range, and the limit of detection is 23 fg·mL −1 . The method breaks the limitation of common ECL ratiometric strategy, namely, two luminophores often share the common coreactant.
Schematic representation of an immunoassay where polyaniline (PANI) in a BSA-Ab 2 -ABEI-Au@PANI composite quenches the cathodic signal of a graphitic carbon nitride (Au-g-C 3 N 4 ) modified with gold nanoparticles (Au), while N-(aminobutyl)-N-(ethylisolumino) (ABEI) in the BSA-Ab 2 -ABEI-Au@PANI composit produces an anodic signal that enables quantitation of calcitonin.
研究领域:
分析化学
·
生物医学工程
·
免疫学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 15
·9381-9392
·
IF 3.108
Qiao Wang,Chandra Sekhar Biswas,Massimiliano Galluzzi,Yuhang Wu,Bing Du,Florian. J. Stadler
Random copolymer gels of N-isopropylacrylamide (NIPAM) and N-ethylacrylamide (NEAM) were synthesized using a 1 : 1 monomer molar ratio in different methanol–water (xm = 0, 0.06, 0.13, 0.21, 0.31 0.43, 0.57, 0.76, where xm = mole fraction of methanol) mixtures. The samples were characterized using different techniques like Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), swelling ratio measurements, deswelling kinetics study, atomic force microscopy (AFM), and rheology. We found that, with the variation of the solvent composition (methanol–water mixtures) the properties of the gels varied significantly. These results can be explained on the basis of the interactions of the two different kinds of monomers with different methanol–water mixtures, their different kinds of thermoresponsiveness and hydrophilicity, and their different cononsolvent properties toward methanol–water mixtures.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2016
·
IF 2.208
Xingdu Chen,Chengjian Yang,Weiwei Wang,Bizhou Ge,Jun Zhang,Yucan Liu,Yaping Nan
The biodegradation characteristic and potential metabolic pathway for removal of environmental N,N-dimethylacetamide (DMAC) by Rhodococcus sp. strain B83 was studied. Rhodococcus sp. strain B83 was isolated from the rhizosphere of a pagoda tree and proved capable of utilizing DMAC as sole source of carbon and nitrogen. Batch culture studies showed that strain B83 could tolerate up to 25 g/L DMAC and showed distinct growth on possible catabolic intermediates except for acetate. The nitrogen balance analysis revealed that approximately 71% of the initial nitrogen was converted to organic nitrogen. DMAC degradation has led to accumulation of acetate and organic nitrogen, meanwhile traces of nitrate and ammonia was build-up but without nitrite. The growth of strain B83 could be inhibited by adding exogenous acetate. By means of the assay of enzymatic degradation of DMAC, several catabolic intermediates at different intervals were observed and identified. Based on the results obtained from culture solution and enzymatic degradation assay, a detailed pathway is proposed for DMAC biodegradation.
研究领域:
环境微生物学
·
生物修复
·
生物降解
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产品关联
DOI
PubMed
高影响因子
Asian Journal of Organic Chemistry
·
2018
·Vol. 7
·期 12
·2527-2533
·
IF 2.496
Wei-Ze Li,Zhong-Xia Wang
Graphical Reaction of quinoline N -oxides and pyridine N -oxides with arylzinc reagents under transition-metal-free conditions was studied. The reaction was carried out in toluene (for quinoline N -oxides) or THF (for pyridine N -oxides) at 100 °C and required 2 equiv. of arylzinc loadings and the presence of 2.5 equiv. of TFAA, affording 2-arylquinolines and 2-arylpyridines, respectively, in 24% to 95% yields. Reaction of quinoline N -oxides and pyridine N -oxides with arylzinc reagents under transition-metal-free conditions was studied. The reaction was carried out in toluene (for quinoline N -oxides) or THF (for pyridine N -oxides) at 100 °C and required 2 equiv. of arylzinc loadings and the presence of 2.5 equiv. of TFAA, affording 2-arylquinolines and 2-arylpyridines, respectively, in 24% to 95% yields. Functional groups OMe, F, Cl, Br, CF 3 , C(O)NH 2 , COOR and NO 2 were tolerated. Mechanistic studies showed that the reaction of quinoline N -oxides proceeded via a 2-arylquinolin-1(2 H )-olate intermediate, and the reaction of pyridine N -oxides via a 5-arylpenta-2,4-dienal oxime intermediate.
研究领域:
有机化学
·
合成化学
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产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2018
·Vol. 135
·期 6
·3363-3373
·
IF 2.209
Zhang Shijie,Zhang Jiaoqiang,Kou Kaichang,Jia Qian,Xu Yunlong,Zerraza Sofiane,Liu Ning,Hu Rongzu
2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexazisowurtzitane (HNIW)·1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) co-crystal in a 2:1 molar ratio was prepared by a solvent/non-solvent method, and the co-crystal has been characterized by several methods. The enthalpies of dissolution of 2HNIW·HMX co-crystal in N,N -dimethylformamide at different temperatures were measured by a DC08-1 Calvet microcalorimeter under standard atmospheric pressure, and it is indicated that the dissolutions are exothermic process. The empirical formulae for the calculation of the molar enthalpy ( \(\Delta_{\text{diss}} H\) ) of dissolution, relative partial molar enthalpy ( \(\Delta_{\text{diss}} H_{\text{partial}}\) ), relative apparent molar enthalpy ( \(\Delta_{\text{diss}} H_{\text{apparent}}\) ), and enthalpy of dilution ( \(\Delta_{\text{dil}} H_{1,2}\) ) at 298.15 K are obtained. The differential enthalpies ( \(\Delta_{\text{dif}} H\) ) and kinetic equations describing the dissolution process at different temperatures are deduced. Furthermore, the apparent activation energy E = 10.54 ± 0.22 kJ mol -1 and pre-exponential constant A = 0.34 ± 0.03 s −1 of 2HNIW·HMX co-crystal are obtained. The standard molar Gibbs free energy of activation ( \(\Delta G_{ \ne }^{\theta }\) ) at different temperatures is 86.44 ± 0.02 kJ mol −1 (298.15 K), 88.02 ± 0.03 kJ mol −1 (303.15 K), 89.61 ± 0.01 kJ mol −1 (308.15 K), 91.18 ± 0.01 kJ mol −1 (313.15 K), and 92.75 ± 0.02 kJ mol −1 (318.15 K), respectively. The standard molar entropy of activation ( \(\Delta S_{ \ne }^{\theta }\) ) and standard molar enthalpy of activation ( \(\Delta H_{ \ne }^{\theta }\) ) are − 262.55 ± 0.72 J mol −1 K −1 and 7.98 ± 0.22 kJ mol −1 , respectively.
研究领域:
物理化学
·
材料科学
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DOI
高影响因子
FIBERS AND POLYMERS
·
2023
·Vol. 24
·期 5
·1879-1890
·
IF 2.5
Zhang Xun,Zhu Zhifeng,Lin Jack
Dimethylaminoethyl (DAE) starch was derived by the tertiary amination of acid-converted maize starch (ACS) with 2-dimethylaminoethyl chloride hydrochloride (DAEC·HCl) for strong bonding to polyester fibers and easy removal from sized yarns. A series of DAE derivatives with differential degrees of substitution (DS) of DAE substituents were prepared through the variation in mole ratio of DAEC·HCl to ACS charged into starch amination. The DAE starch was characterized by FTIR spectroscopy, DS value, amination efficiency and paste viscosity. The bonding strength was measured using a legal method (FZ/T 15,001–2008) while the desizability was accessed by Hank sizing and oxidant-alkali desizing. The results showed that the amination was able to significantly improve the bonding strength to polyester fibers under mild acidic condition and could prevent the difficulty encountered in quaternized starch desizing. The DAE starch could compete with ACS in desizability during oxidant-alkali desizing. As a result, introduction of DAE groups onto ACS was an effective method for achieving a starch based sizing material with strong bonding and good desizability. Based on the achievements obtained in this work, the DAE starch with a DS value of 0.037–0.058 DAE substituents showed potential application in polyester warp sizing.
研究领域:
材料科学
·
纺织工程
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DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2023
·
IF 2.6
Jinbei Yang,Yichun Huang,Yang Wang,Jinyi Chen,Meiqiong Yu
Isobaric vapor–liquid equilibrium (VLE) data for the four binary systems of n-butyric acid with water, isopropyl acetate, n-propyl acetate, and n-methylpyrrolidone were measured experimentally by a modified Rose still at the local atmospheric pressure of 99.8 kPa. All of the experimental VLE data for the four binary systems passed the Van Ness thermodynamic consistency test. Two activity coefficient models, namely, the NRTL and Wilson models, were selected to correlate the VLE data, and the binary interaction parameters were regressed with the two models. The result indicates that a homogeneous azeotropic behavior can be found for the two binary systems of water + n-butyric acid and n-butyric acid + n-methylpyrrolidone, and the obtained VLE data correlate well with the two models. There is no binary azeotropic behavior between n-butyric acid and isopropyl acetate/n-propyl acetate, indicating that isopropyl acetate and n-propyl acetate can be used as extractants and azeotropic agents for the extraction–azeotropic distillation separation of n-butyric acid and water.
研究领域:
化学工程
·
物理化学
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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）