INORGANIC CHEMISTRY
·
2020
·
IF 4.825
Wenbo Yang,Andrei A. Sukhanov,Jong Hyeon Lim,Xiaoxin Li,Yinshan Meng,Jianzhang Zhao,Haoling Sun,Jin Yong Lee,Gagik G. Gurzadyan,Violeta K. Voronkova
To study the effect of a stable radical on the photophysical properties of a phosphorescent Pt(II) coordination framework and the intramolecular magnetic interaction between radical ligands in the N^N Pt(II) bisacetylide complexes, we prepared a series of N^N Pt(II) bis(acetylide) complexes with oxoverdazyl radical acetylide ligands. The linker between the Pt(II) center and the spin carrier was systematically varied, to probe the effect on the sign and magnitude of the spin exchange interactions between the radical ligands and photophysical properties. The complexes were studied with steady-state and femtosecond/nanosecond transient absorption spectroscopy, continuous-wave electron paramagnetic resonance (EPR) spectroscopy, and density functional theory (DFT) computations. The transient absorption spectral studies show that the doublet excited state of the radicals are short-lived (τD ≈ 2 ps) and nonfluorescent. Moreover, the intrinsic long-lived triplet excited state (τT = 1.2 μs) of the Pt(II) coordination center was efficiently quenched by the radical (τT = 6.9 ps for one representative radical Pt(II) complex). The intramolecular magnetic interaction between the radical ligands through the diamagnetic Pt(II) atom was studied with temperature-dependent EPR spectroscopy; antiferromagnetic exchange interaction (−J S1S2, J = −5.4 ± 0.1 cm–1) for the complex with the shortest radical–radical distance through bridge fragments was observed. DFT computations give similar results for the sign and magnitude of the J values. For complexes with larger inter-radical distance, however, very weak coupling between the radical ligands was observed (|J| < 0.7 cm–1). Our results are useful for the study of the effect of a radical on the photophysical properties of the phosphorescent transition-metal complexes.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2019
·
IF 6.044
Yuxue Gao,Shiyu Zong,Yirong Huang,Na Yang,Hankang Wen,Jianxin Jiang,Jiufang Duan
An oxidation-reduction responsive degradable highly elastic galactomannan hydrogel was synthesized from galactomannan (GA), N,N -bis (acryloyl) cysteamine (BAC) and acrylamide by grafting polymerization in aqueous solution. The microstructure, degradability and mechanical properties of the hydrogels were emphatically investigated using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), ultraviolet spectroscopy and differential scanning calorimetry (DSC). The mechanical properties of hydrogels can be improved by adjusting the content of GA. Continuous cyclic compression tests showed that the hydrogel did not rupture under 60 %,70 %,80 % strain and quickly recovered to its original shape. The degradation rate and drug release rate of hydrogel can be adjusted by the concentration of the reductant and the reduction time. These hydrogels broaden the scope of application of GA and can be tuned with a broad range of mechanical, degradation and release properties and therefore hold potential applications in drug carriers, tissue engineering scaffolds, extracellular matrix and other fields.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2023
·
IF 11.1
Zeying Yang,Boyong Cao,Yi Cao,Xiaowei An,Xiyan Yue,Guoqing Guan,Yanhao Zhang,Baoxian Ye,Zhengkun Xie
Emerging contaminant N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine has caused severe threats to ecosystems, necessitating the development of highly sensitive detection methods. Herein, a reliable and ultra-sensitive electrochemical sensor based on a carbon paste electrode modified by hexagonal wurtzite zinc oxide was developed for selective determination and degradation of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine. Experimental results demonstrated the successful application of the sensor for detecting N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine in soil samples. The contaminant contents were found to be 1.46–24.68 nmol L −1 in Zhengzhou City and 1.99–11.3 nmol L −1 in Pingdingshan City, respectively, along with a satisfactory recovery rate. Density functional theory calculations revealed that the hexagonal wurtzite zinc oxide crystal significantly decreased the activation energy of catalytic conversion compared to cubic sphalerite , resulting in a notable improvement in sensor response. Cryogenic electron microscopy technique further confirmed that the electrocatalytic degradation product of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine was not toxic N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine quinone . Under optimal analysis conditions, the sensor achieved widely low as well as high linear ranges (0.1–800 nmol L −1 and 0.9–20 μmol L −1 ) with a low detection limitation (33 pmol L −1 ), indicating that such a highly sensitive and cost-effective electrochemical sensor has the potential for environmental pollutants monitoring .
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2023
·
IF 2.6
Xin Huang,Qiufen Wang,Shouxiang Jiang,Bin Wang,Wenjun Xie,Chengfei Wang,Haoran Li,Guan Wang,Gengxiu Zheng
The solubility of N,N’-oxalyldiglycine (OG) in 11 pure solvents, including methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol, acetonitrile, ethyl acetate, tetrahydrofuran (THF), water, N,N’-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), and a binary solvent system composed of DMSO and water was measured by a dynamic laser monitoring method with the temperature ranging from 293.15 to 333.15 K. Results of these experiments demonstrated that the solubility of OG in all pure solvents increases with rising temperature. The highest solubility appeared in DMSO while the lowest solubility appeared in ethyl acetate. Besides, the mole fraction solubility of OG in binary solvents increases with increasing content of DMSO. Furthermore, the experimental solubility of OG in pure solvents was correlated with the modified Apelblat, Van’t Hoff, λh, and Wilson models. Four models (Van’t Hoff, CNIBS/R–K, modified Jouyban–Acree, and Wilson) were used for the binary solvents. The Van’t Hoff model best correlates with the experimental values in pure and binary solvents, and the calculated values by the Wilson model have a large deviation from the experimental values.
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Xin Zhang,Yiming Zhao,Wenjuan Li,Yun Zhang,Siyu Xu,Sen Xu,Wen Zhou,Yizheng Fu,Yongan Feng,Weiguo Cao
Higher fatty alcohols play a vital position in modern industry, while the dust explosion hazard cannot be ignored. Three kinds of linear monohydric alcohols CH 3 (CH 2 ) n-1 OH (n = 16, 18, 22) were selected to explore the combustion characteristics through ignition tests and molecular dynamics simulations. The experiment consequences indicated that the flame propagation height of alcohols dust gradually aggrandized as the enlargement of dust concentration of 30–750 g/m 3 and the flame propagation velocity presented two peaks. CH 3 (CH 2 ) 15 OH had the highest flame propagation height and velocity, followed by CH 3 (CH 2 ) 17 OH and CH 3 (CH 2 ) 21 OH. The first flame propagation velocities of CH 3 (CH 2 ) 15 OH, CH 3 (CH 2 ) 17 OH, and CH 3 (CH 2 ) 21 OH reached the maximum value at 500 g/m 3 , which were 16.47, 13.25, and 12.53 m/s, respectively. The second peak reached the maximum value at 750 g/m 3 , which were 20.07, 19.05, and 18.23 m/s, respectively. The combustion reactions of alcohols revealed that the decomposition of molecules was first due to the breakage of the C C bond, and the main products were mainly C 2 H 4 , H 2 O, CH 2 O, CO, and CO 2 . The production and consumption reaction processes of C 2 H 4 , CH 2 O, and other combustible gas products reasonably explained the flame continuous process and the variation of flame propagation. The TG test results indicated that the volatility and thermal conductivity of CH 3 (CH 2 ) 15 OH, CH 3 (CH 2 ) 17 OH, and CH 3 (CH 2 ) 21 OH decreased sequentially, which confirmed the flame propagation and molecular dynamics combustion reactions of the three alcohols. The volatility of alcohols was the key factor determining the difference in the flame propagation behavior of alcohols dust.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Hongmin Cui,Xuejiao Feng,Jinsong Shi,Wengang Liu,Nanfu Yan,Guohua Rao,Wei Wang
Separation of rare earth elements (REEs) from dilute solutions using liquid-liquid extraction is often plagued by third phase formation and multiple sequential extraction steps. A new system based on the N, N-di(2-ethylhexyl)-diglycolamide (DEHDGA) grafted polymer resin, used for the efficient separation of RE(III) are proposed. Upon grafting of DEHDGA ligand, the resulting polymer resin was evaluated for its RE(III) adsorption performance. By using a combination of pH-dependent adsorption, kinetics and equilibrium adsorption isotherms experiments, the results suggest that adsorption behavior of the resin for RE(III) is mainly influenced by pH, and thus a competitive adsorption model is proposed to simultaneously describe the adsorption of RE(III) and protons. The proposed resin demonstrates enhanced selectivity towards RE(III) in the presence of Al(III) and Fe(III) compared to the DGA-normal resin at pH 3.0. These results establish that the polymer skeleton could provide a favorable geometry of DEHDGA ligand for complexing RE(III) through the carbonyl and ether groups, which is supported by the FT-IR and XPS analysis of prepared RE(III)-loaded resin. Furthermore, the polymer resin could be reused after four consecutive cycles without substantial loss of adsorption ability, offering a facile process for highly efficient REEs separation from a low concentration of leaching solution.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2018
·
IF 2.631
Wentian Li,Nan Zhang,Ali Farajtabar,Xingang Feng,Gaoquan Chen,Xinbao Li,Hongkun Zhao
Experimental measurement of drug quinocetone solubility in water-co-solvent mixtures of ethanol, isopropanol, dimethyl sulfoxide (DMSO) and N,N -dimethylformamide (DMF) were determined by the static equilibrium method at temperature range of (283.15–328.15) K under ambient condition (101.2 kPa). The solid phase equilibrated with liquor was examined by X-ray power diffraction, resulting in no polymorphic transformation, solvate formation or crystal transition compared to the raw material. Quantitative knowledge about the solvent effect on the solubility was obtained with the help of linear solvation energy relationships in the terms of dipolarity-polarizability, hydrogen-bond donor and acceptor ability, and cavity term of mixtures. The preferential solvation was investigated from their thermodynamic solution properties by means of the inverse Kirkwood-Buff integrals. The preferential solvation parameters ( δx 1,3 ) for ethanol, isopropanol, DMSO or DMF were negative in the four co-solvent mixtures with water-rich compositions, which indicated that quinocetone was preferentially solvated by water. Temperature has a little effect on the preferential solvation magnitudes for the ethanol and isopropanol mixtures. The higher solvation by water could be explained in terms of the higher acidic behavior of the solvents interacting with the Lewis basic groups of the quinocetone. In addition, thermodynamic co-solvency models including the Jouyban-Acree model, van’t Hoff-Jouyban-Acree model and Modified Apelblat-Jouyban-Acree model were employed to describe the solubility of this drug obtaining average relative deviations lower than 2.14% and root-mean-square deviations lower than 1.75 × 10 −4 for correlative studies. The standard dissolution enthalpies of quinocetone in the solvent mixtures were positive, demonstrating that the dissolution process of quinocetone was endothermic.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Hao Ling,Hongxia Gao,Zhiwu Liang
The physical solubility and mass transfer performance of CO 2 absorption into aqueous N,N-dimethylethanolamine (DMEA) solution were comprehensively studied in the present work. The physical solubility (Henry’s law constant ( He )) was measured using a stirred cell reactor for pure DMEA and aqueous DMEA at temperatures from 293.98 to 333.03 K. Then, the physical solubility of CO 2 was obtained based on the “N 2 O analogy” method. Furthermore, He was correlated successfully by using an empirical polynomial model with an average absolute relative deviation (AARD) of 4.23%. The mass transfer performance was studied in a laboratory scale structured packing absorption column at DMEA concentration of 1–4 kmol/m 3 , liquid feed temperature of 293.15–333.15 K, liquid flow rate of 3.90–11.7 m 3 /m 2 -hr, CO 2 partial pressure of 6–20 kPa, lean CO 2 loading of 0.050–0.300 mol/mol, over the inert gas flow rate range of 26.11–43.52 kmol/m 3 -hr. Based on the experimental values of He for CO 2 into aqueous DMEA solution, the effect of the gas concentration of A in gas-liquid equilibrium ( y A ∗ ) on gas phase volumetric overall mass transfer coefficient ( K G a v ) was considered in this study, but found to be an insignificant influence that can be ignored. Analogously, an attempt to correlate the mass transfer coefficient K G a v and outlet concentration of CO 2 ( y out ) using semiempirical models as function of the mentioned operational parameters was conducted. The predictive correlations for K G a v and y out of the DMEA-CO 2 -H 2 O system in structured packing column are K G a v = L 0.23 0.6144 a eq - a C / p C O 2 + 0.02327 and ln y out = l n y in - 0.77 PV G Ω L 0.23 0.6144 a eq - a C / p C O 2 + 0.02327 , with acceptable AARDs of 4.59% and 1.48%, respectively.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2018
·
IF 5.651
Hengjun Gai,Caiyun Zhong,Lin Qiao,Shuo Chen,Meng Xiao,Hongbing Song
Wastewater containing 1-amino-2-naphthol-4-sulfonic acid (ANS) is mainly derived from the dye production process, causing serious environmental problems. In this work, extraction of ANS from wastewater was carried out using trioctylamine (TOA) under condition of methyl isobutyl ketone (MIBK) as a diluent. The effects of diluent type, concentration of TOA, temperature and pH on the distribution coefficient (D) were discussed in detail. The results showed that the value of D = 76 was obtained with TOA (1.41 mol kg −1 ) + MIBK at 25 °C and pH = 1.1. After that, the extraction mechanism was determined by analyzing the chemical bonds of the complex compound using UV–vis, FT-IR and 1 H NMR. The experimental results showed that the extractant could be regenerated by back extraction. Specially the distillation process was simulated using Aspen Plus and the results verified its feasibility in the process of extractant regeneration. The proposed extraction system is conductive to both environment and technology .
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2017
·
IF 3.034
Li Luo,Yuan Yang,Qiang Wang,Hai-pu Li,Zhou-fei Luo,Zhi-peng Qu,Zhao-guang Yang
The presence of endocrine disrupting chemicals such as 4- n -octylphenol, 4- n -nonylphenol and bisphenol A in environmental samples and artificial products may cause health problems for human and organisms. This developed method was efficient for monitoring of those tracing emerging contaminates and the Plackett-Burman factorial design introduced in extraction step was timesaving. Matrix effect was also considered to ensure proper quantitation. Good linearity (r 2 > 0.99), low Method Detection Limits (MDL) and Method Quantitation Limits (MQL) range from 0.18 to 0.54 ng/g and 0.60 to 1.80 ng/g were obtained. Three level spiking experiment (4, 10, 15 ng/g) showed recoveries range from 74% to 113% for 4- n -octylphenol and 4- n -nonylphenol with RSD range from 2% to 11%. The method was finally applied to the analysis of real fish samples taken from Hunan Province, China, offering a reliable and effective means for monitoring of trace emerging contaminates in fishes largely consumed by residents.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2014
·Vol. 173
·期 8
·2005-2018
·
IF 1.687
Yao Huiqin,Lin Ling,Wang Peng,Liu Hongyun
Dual-responsive poly( N , N -diethylacrylamide) (PDEA) hydrogel films with entrapped horseradish peroxidase (HRP) and glucose oxidase (GOD) were successfully prepared on electrode surface with a simple one-step polymerization procedure under mild conditions, designated as PDEA-HRP-GOD. Cyclic voltammetric (CV) response of electroactive probe K 3 Fe(CN) 6 at the film electrodes displayed reversible thermo- and sulfate-responsive switching behavior. For example, at 25 °C, the K 3 Fe(CN) 6 demonstrated a well-defined CV peak pair with large peak currents for the films, showing the on state, while at 40 °C, the CV response was greatly suppressed and the system was at the off state. The influence of temperature and Na 2 SO 4 concentration on the switching behavior of the film system was not independent or separated, but was synergetic. The responsive mechanism of the system was ascribed to the structure change of PDEA component in the films with temperature and sulfate concentration. This switching property of the PDEA-HRP-GOD films could be further used to realize dual-responsive catalytic oxidation of glucose sequentially by HRP and GOD entrapped in the films with Fe(CN) 6
3− as the mediator through changing the surrounding temperature and Na 2 SO 4 concentration. This system may establish a foundation for fabricating a new type of multi-switchable electrochemical biosensors based on bienzyme electrocatalysis.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Ming-Yang He,Pin-Xi Wang,Jun-Qing Ye,Wen-Wen Chen,Jun-Feng Qian,Qun Chen
The development of highly active catalysts for the direct synthesis of N,N’-diphenylurea (DPU) from CO 2 and aniline is crucial yet has faced significant challenges. This study introduces a metal oxide composite catalyst, Cu x Fe 0.5 Ce 0.5 , synthesized via a one-step co-precipitation method. This catalyst features both acidic and basic active sites that synergistically catalyze the conversion of CO 2 and aniline into DPU with high efficiency. It achieved an aniline conversion rate of up to 33.0 % and an exceptional DPU selectivity of 99.9 %. Comprehensive characterizations confirmed that the catalyst possesses well-defined morphology, controlled size, optimized pore structure, and robust acid-base properties, along with abundant oxygen vacancies. Specifically, CuFe components function as Lewis base sites, effectively activating CO 2 molecules, while Ce 3+/4+ species serve as Lewis acid sites, facilitating the adsorption and activation of aniline to form key intermediates. Importantly, the presence of oxygen vacancies enhances electronic interactions between CeO 2 and metals, increasing metal electron density and providing critical active sites for CO 2 adsorption and activation, thus promoting the efficient catalytic reaction progression. Moreover, the catalyst demonstrates excellent reusability, maintaining approximately 95 % of its catalytic efficiency after five cycles. This work provides an innovative approach to developing efficient catalysts for the valorization of CO 2 into higher value-added chemicals.
✓ 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）