JOURNAL OF CATALYSIS
·
2017
·
IF 6.844
Yan Cao,Zipeng Xing,Mengqiao Hu,Zhenzi Li,Xiaoyan Wu,Tianyu Zhao,Ziyuan Xiu,Shilin Yang,Wei Zhou
Mesoporous black N-TiO 2−x hollow spheres are successfully fabricated through a facile evaporation-induced self-assembly (EISA) process, coupled with an etching procedure and an in-situ solid-state chemical reduction strategy. The resultant black N-TiO 2−x hollow spheres with high crystallinity possess a narrow band gap of ∼2.37 eV, a large specific surface area of ∼128 m 2 g −1 , and a well defined hollow sphere structure, which exhibit excellent visible-light-driven photocatalytic performance for degradation of phenol , reduction of Cr(IV), and hydrogen production . The photocatalytic reaction apparent rate constants (k) of the black N-TiO 2−x for phenol degradation and Cr(IV) reduction are ∼5 and 6 times higher than that of pristine TiO 2 , and hydrogen production rate for N-TiO 2−x is ∼160 μmol h −1 , which is ∼7 folds higher than that of pristine one. The excellent photocatalytic and photoreduction property can be attributed to the synergy effect of N and Ti 3+ codoping narrowing the band gap, the high specific surface area offering more surface active sites, and the mesoporous hollow structure favoring light harvesting and refraction.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 43
·45444
·
IF 1.86
Fuchen Zhang,Qiuxia Wang,Lipeng Wang,Yongping Bai
This article describes the implementation of plant-derived isosorbide (IS) and isomannide (IM) in the copolymerization modification of poly(ethylene terephthalate). The effects of the two comonomers on the optical, crystallization, and thermal properties of the resulting copolyesters were studied using the following analytical methods: proton nuclear magnetic resonance; differential scanning calorimetry; X-ray diffraction; thermogravimetry; and ultraviolet-visible spectroscopy. As comonomers, IS and IM increased the transmittance and reduced the haze of the copolyesters. Moreover, while IM improved the optical properties more than did IS, both monomers improved the optical properties of the copolyesters by lowering its crystallization ability. After the copolymerization modification, the crystallization rate of the copolyesters was reduced, decreasing the crystallinity and crystal size and thereby reducing the light transmission interference. The comonomers also altered the light absorption properties of the copolyesters and conferred a substantial increase in the transmittance of near-infrared (NIR) wavelengths. These changes in optical properties exhibit the potential of these comonomers for applications in optical materials and NIR detectors. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45444.
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2017
·
IF 6.942
Guangsen Xia,Yujue Wang,Bin Wang,Jun Huang,Shubo Deng,Gang Yu
Previous studies indicate that effective generation of hydrogen peroxide (H 2 O 2 ) from cathodic oxygen (O 2 ) reduction is critical for the improved water treatment performance (e.g., enhanced pollutant degradation and reduced bromate formation) during the electro-peroxone (E-peroxone) process (a combined process of electrolysis and ozonation). However, undesired reactions (e.g., O 3 , H 2 O 2 , and H 2 O reductions) may occur in competition with O 2 reduction at the cathode. To get a better understanding of how these side reactions would affect the process, this study investigated the cathodic reaction mechanisms during electrolysis with O 2 /O 3 gas mixture sparging using various electrochemical techniques (e.g., linear sweep voltammetry and stepped-current chronopotentiometry). Results show that when a carbon brush cathode was used during electrolysis with O 2 /O 3 sparging, H 2 O and H 2 O 2 reductions were usually negligible cathodic reactions. However, O 3 can be preferentially reduced at much more positive potentials (ca. 0.9 V vs. SCE) than O 2 (ca. −0.1 V vs. SCE) at the carbon cathode. Therefore, cathodic O 2 reduction was inhibited when the process was operated under current limited conditions for cathodic O 3 reduction. The inhibition of O 2 reduction prevented the desired E-peroxone process (cathodic O 2 reduction to H 2 O 2 and ensuing reaction of H 2 O 2 with O 3 to OH) from occurring. In contrast, when cathodic O 3 reduction was limited by O 3 mass transfer to the cathode, cathodic O 2 reduction to H 2 O 2 could occur, thus enabling the E-peroxone process to enhance pollutant degradation and mineralization. Many process and water parameters (applied current, ozone dose, and reactivity of water constituents with O 3 ) can cause fundamental changes in the cathodic reaction mechanisms, thus profoundly influencing water treatment performance during the E-peroxone process. To exploit the benefits of H 2 O 2 in water treatment, reaction conditions should be carefully controlled to promote cathodic O 2 reduction during the E-peroxone process.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 103
·100891-100898
·
IF 3.289
Kun Peng,Qiqin Wang,Weijia Chen,Donghai Xia,Zhengyin Zhou,Yuqiang Wang,Zhengjin Jiang,Fuhai Wu
A novel phosphatidic acid functionalized polymeric monolithic column was prepared through the thermally initiated co-polymerization of 12-methacryloyl dodecylphosphatidic acid (MDPA) and ethylene glycol dimethacrylate (EDMA) in the presence of 1,4-butanediol and isopropanol as porogens within 100 μm I.D. capillaries. The polymerization conditions of monolithic columns were systematically optimized in order to obtain good permeability, stability and column efficiency. The reproducibility of the optimized monolithic column was also satisfactory. The physicochemical properties of the monolithic column were evaluated by use of instrumental techniques including scanning electron microscopy, Fourier transform infrared spectra, ζ-potential analysis and micro-HPLC. A series of test compounds such as small peptides, alkylphenones, etc., were employed to investigate the retention mechanism on the poly(MDPA-co-EDMA) monolithic column. The results demonstrate that both hydrophobic and cation-exchange interactions could contribute to the overall retention of analytes. Furthermore, the novel reversed-phase/cation-exchange mixed mode monolithic column was applied to the separations of small peptides, phenols, water-soluble vitamins B, and pharmaceutical compounds. The successful applications indicate the potential of the poly(MDPA-co-EDMA) monolithic column in complex sample analysis.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2016
·
IF 3.926
Haibin Li,Chusheng Liu,Qiqin Wang,Haibo Zhou,Zhengjin Jiang
In order to investigate the effect of charged groups present in hydrophilic monolithic stationary phases on their chromatographic properties, three charged hydrophilic monomers, i.e. N,N -dimethyl- N -acryloyloxyethyl- N -(3-sulfopropyl)ammonium betaine (SPDA), [2-(acryloyloxy)ethyl]trimethylammonium chloride (AETA), and 3-sulfopropyl acrylate potassium salt (SPA) were co-polymerized with the crosslinker N,N '-methylenebisacrylamide (MBA), respectively. The physicochemical properties of the three resulting charged hydrophilic monolithic columns were evaluated using scanning electron microscopy, ζ-potential analysis and micro-HPLC. High column efficiency was obtained on the three monolithic columns at a linear velocity of 1 mm/s using thiourea as test compound. Comparative characterization of the three charged HILIC phases was then carried out using a set of model compounds, including nucleobases, nucleosides, benzoic acid derivatives, phenols, β-blockers and small peptides. Depending on the combination of stationary phase/mobile phase/solute, both hydrophilic interaction and other potential secondary interactions, including electrostatic interaction, hydrogen-bonding interaction, molecular shape selectivity, could contribute to the over-all retention of the analytes. Because of the strong electrostatic interaction provided by the quaternary ammonium groups in the poly (AETA- co -MBA) monolith, this cationic HILIC monolith exhibited the strongest retention for benzoic acid derivatives and small peptides with distorted peak shapes and the weakest retention for basic β-blockers. The sulfonyl groups on the poly (SPA- co -MBA) hydrophilic monolith could provide strong electrostatic attraction and hydrogen bonding for positively charged analytes and hydrogen-donor/acceptor containing analytes, respectively. Therefore, basic drugs, nucleobases and nucleotides exhibited the strongest retention on this anionic monolith. Because of the weak but distinct cation exchange properties of the zwitterionic poly (SPDA- co -MBA) hydrophilic monolith, it exhibited the best separation for most test analytes (including phenols, β-blockers and small peptides) in terms of selectivity, peak shape and analysis time. The poly (AETA- co -MBA) hydrophilic monolithic column provides the best separation of nucleobases and nucleosides. These results could guide the selection and application of these charged HILIC monoliths in the future.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE CHEMICAL LETTERS
·
2017
·
IF 1.932
Zhen-Zhen An,Zhuang Li,Yong-Yang Guo,Xiao-Ling Chen,Kang-Ning Zhang,Dong-Xia Zhang,Zhong-Hua Xue,Xi-Bin Zhou,Xiao-Quan Lu
In this work, the chitosan and N-doped graphene natively grown on hierarchical porous carbon (N-PC-G/CS) nanocomposite was obtained by ultrasonic method, as a novel sensor platform for determination of tartrazine (TT). The nanocomposite as prepared had well dispersivity in water and excellent conductivity. The N-PC-G/CS nanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption-desorption, fourier transform infrared (FTIR) and electrochemical impedance spectroscopy (EIS). The application of N-PC-G/CS for determination of tartrazine (TT) was investigated by chronocoulometry (CC), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under optimized conditions, the sensor displayed a sensitive response to TT within a wide concentration range of 0.05–15.0 μmol/L, the detection limits is 0.036 μmol/L (S/N = 3). Furthermore, this nanocomposite could be efficiently applied for determination of TT in soft drink samples.
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2017
·Vol. 22
·期 2
·337
·
IF 2.861
Fang Li,Wai Szeto,Haibao Huang,Jiantao Li,Dennis Y. C. Leung
A photocatalytic rotating disc reactor (PRD-reactor) with TiO2nanowire arrays deposited on a thin Ti plate is fabricated and tested for industrial wastewater treatment. Results indicate that the PRD-reactor shows excellent decolorization capability when tested with methyl orange (>97.5%). Advanced oxidation processes (AOP), including photocatalytic oxidation and photolytic reaction, occurred during the processing. Efficiency of the AOP increases with reduction in light absorption pathlength, which enhanced the photocatalytic reaction, as well as by increasing oxygen exposure of the wastewater thin film due to the rotating disc design. It is found that, with a small dosage of hydrogen peroxide, the mineralization efficiency of industrial biodegraded wastewater can be enhanced, with a superior mineralization of >75% total organic carbon (TOC) removal. This is due to the fact that the TiO2photocatalysis and hydrogen peroxide processes generate powerful oxidants (hydroxyl radicals) that can strongly improve photocatalytic oxidation efficiency. Application of this industrial wastewater treatment system is benefited from the TiO2nanowire arrays, which can be fabricated by a mild solvothermal method at 80 °C and under atmospheric pressure. Similar morphologies and microstructures are found for the TiO2nanowire arrays deposited on a large metal Ti disc, which makes the wastewater treatment process more practical and economical.Keywords:TiO2nanowire arrays;photocatalytic rotating reactor;wastewater treatment
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MINERAL PROCESSING
·
2017
·
IF 1.561
Yichang Yu,Zhangjun Hu,Yue Wang,Hongwen Gao
A magnetic nano-scaled composite was synthesized by self-assembly of cationic surfactant octadecyl dimethyl hydroxyethyl ammonium nitrate (SN) into natural mineral diatomite via a ‘dissolution and reassembly’ method. Fourier transform infrared (FT-IR), elemental analysis, scanning electron microscopy (SEM), transmission electron microscope (TEM), surface area and magnetic analysis were performed to characterize the achieved composites. The results indicated that SN and Fe 3 O 4 nanopartilces were successfully inserted into the diatomite matrix. Under the same condition, the mixed phenols adsorption experiments showed that the maximum adsorption capacity of phenols by the composite was in order of 2,4,6-trichlorophenol > 2,6-dichlorophenol > 2,4-dichlorophenol > p-nitrophenol > m-methylphenol > phenol, the same as the competitive adsorption ability. The adsorption process obeyed the Langmuir isothermal model. 2,6-Dichlorophenol was used as a representative contaminant to further investigate the mechanism of adsorption. Electrostatic interaction and hydrophobic stacking effect might play important roles in the adsorption towards organic phenols. Owing to the embedded magnetic Fe 3 O 4 , the composite was able to be separated easily from liquid media under an external magnetic field. The further calcination of the used composites showed a possibility to deliver new magnetic mesoporous absorbents for further use.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2017
·
IF 3.648
Jiahong Zhu,Keke Yu,Yugang Zhu,Ruyu Zhu,Fangfang Ye,Ning Song,Yingjie Xu
Three deep eutectic solvents (DESs) were synthesized using choline chloride (ChCl) and phenolic compounds (phenol, p -cresol, and p -chlorophenol) as hydrogen bond donors (HBD) with a molar ratio of 1:2 (ChCl:HBD). Densities ( ρ ), viscosities ( η ), and refractive indices ( n D ) of DESs were measured at T = (293.15 to 333.15) K under atmospheric pressure. Temperature dependence of ρ and η were fitted by empirical equations, and thermal expansion coefficient ( α p ) and activation energy for viscous flow ( E η ) were obtained accordingly. FT-IR spectra of DESs were determined and compared with the corresponding HBDs. Based on physicochemical properties and FT-IR spectra, the influence of electronic effect of substitution group of HBD on hydrogen bond interaction between ChCl and HBD was explored. The results show that the electronic effect of HBD plays an important role on the strength of hydrogen bond interaction of O H ⋯ Cl − of DES. The strong electron-withdrawing property of Cl group of p -chlorophenol can strengthen the hydrogen bond interaction of O H ⋯ Cl − , which leads to higher ρ , η , and n D of DES formed by ChCl and p -chlorophenol. Conversely, CH 3 group of p -cresol exhibits electron-donating effect, resulting in weaker hydrogen bond interaction and lower ρ and n D of DES formed by ChCl and p -cresol. Consequently, the strength of hydrogen bond interaction of O H ⋯ Cl − between ChCl and HBD of DES is as follows: p -chlorophenol > phenol > p -cresol.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2017
·Vol. 409
·期 10
·2531-2537
·
IF 3.431
Cheng Hao,Wu Shubin,Huang Jinbao,Zhang Xiaohua
Although o -quinonemethide (6-methylene-2,4-cyclohexadien-1-one) has been proposed as a key intermediate in char formation during the pyrolysis of guaiacol (2-methoxyphenol), direct evidence of this (e.g., spectroscopic data) has not yet been provided. Using in situ FTIR spectroscopy, the pyrolysis of guaiacol was investigated from 30 °C to 630 °C at 40 °C/min. The IR profiles showed direct evidence of o -quinonemethide production at about 350 °C, which vanished rapidly at around 420 °C in the vapor phase, indicating char formation. In addition, at 400 °C, salicyl aldehyde was observed, which decomposed slowly at about 500 °C. In combination with the known products of guaiacol pyrolysis, these results allowed the major reaction pathways of guaiacol pyrolysis to be discerned. Density functional theory calculations were performed, and the results were found to be in good agreement with the experimentally obtained IR profiles. These findings provide guidance on how to suppress secondary reactions of guaiacol during lignin pyrolysis.
On-line analysis of pyrolysis process of guaiacol using in situ FTIR
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CATALYSIS COMMUNICATIONS
·
2017
·
IF 3.33
Junyi Liu,Hua Huang,Xianxiang Liu,Jiafu Xiao,Sheng Zhong,Xichun She,Zaihui Fu,Steven Robert Kirk,Dulin Yin
A series of Fe 2 O 3 doped SBA-15 materials were prepared via an equivalent-volume impregnation method. The resultant Fe 2 O 3 -containing SBA-15 materials showed good performance in phenol methylation . Under the same conditions, the mesoporous catalyst with 5 wt.% Fe 2 O 3 showed the superior catalytic activity to that of pristine α -Fe 2 O 3 even at lower reaction temperature (320 °C vs. 350 °C). The elevated catalytic activity observed for the mesoporous catalyst could be due to high level dispersion of Fe 2 O 3 species in the mesoporous framework. Furthermore, the mesoporous catalyst possessed long lifetimes, which could be used continuously for 2000 h without significant loss of activity.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2017
·
IF 3.359
Xiang Li,Minghua Zhou,Yuwei Pan,Liting Xu,Zhuoxuan Tang
Advanced oxidation processes (AOPs) has great potential for wastewater treatment, but still limited in application due to their high cost for extensive reagent and energy demand, and restricted working conditions (e.g. narrow pH range). Here, AOPs based on pre-magnetization Fe 0 (Pre-Fe 0 ) were found to be highly efficient at wider pH conditions, partly solved the above problems. After pre-magnetization, Fe 0 was supposed to be easier to be corroded, which remarkably improved processes (e.g., Pre-Fe 0 /H 2 O 2 , Pre-Fe 0 /K 2 S 2 O 8 ) efficiency several to >100 folds and valid for many refractory contaminants (e.g. dyes, phenols, organic acids), compared with that conventional processes without pre-magnetization. Moreover, the process efficiency could be sustained by the recovery of magnetism of Pre-Fe 0 . Thus AOPs based on pre-Fe 0 is more promising to take place of conventional Fe 0 based AOPs since it is more efficient but does not require any change of the present water and wastewater treatment process, and does not need an extra energy source, costly materials, and complex equipment.
✓ 已验证
产品关联
DOI
高影响因子