SENSORS AND ACTUATORS B-CHEMICAL
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2017
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IF 5.401
Haifeng Zhou,Tingting Huang,Dejian Chen,Shunxing Li,Huiwu Yu,Yuhui Li,Qijun Song
Copper nanoparticles modified nitrogen doped reduced graphene oxide 3-D superstructure was successively prepared via a two-step reaction. Polydopamine was used as nitrogen source for the fabrication of nitrogen doped reduced graphene oxide and reducing agent for in-situ reduction of CuCl 2 . After calcination under nitrogen protection, the conductivity, electron transfer ability and electrocatalytic activity of nanocomposites were substantially improved. The enhanced redox property could be attributed to the difference in the electronegativity of carbon and nitrogen atoms of the 3-D superstructure. By using this composite material, an electrochemical sensor was constructed for the detection of dihydroxybenzene isomers, which exhibited excellent sensitivity (with limit of detection at 81•131 nmol L ∧1 levels), wide linear ranges (0.5•720 α/4mol L ∧1 ) and good selectivity. Hence it was directly applied for the simultaneous determination of dihydroxybenzene isomers in contaminated samples (e.g., waste waters).
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高影响因子
ACS Sustainable Chemistry & Engineering
·
2016
·
IF 5.267
Yao Liu,Yirong Zhou,Junxi Zhang,Yongyao Xia,Tong Chen,Shiming Zhang
Sodium iron phosphate (Na3Fe2(PO4)3) as cathode material for sodium-ion batteries has been synthesized through a simple method of a solid state reaction. It crystallizes in a monoclinic structure in the space group C2/c. The morphology of the as-prepared sample has been investigated by scanning electron microscopy and transmission electron microscopy. The charge/discharge curves show a very flat plateau at about 2.5 V (vs Na/Na+). The initial specific discharge capacity is 61 mAh g–1 and remains at 57 mAh g–1 after 500 cycles at a current rate of 1 C. X-ray photoelectron spectroscopy measurements indicate that not all of the Fe3+ of Na3Fe2(PO4)3 is reduced during the electrochemical process. The ex-situ X-ray diffraction measurements were applied to research the mechanism of sodium-ion storage; the results indicated that the Na3Fe2(PO4)3 compound partly transformed into Na4Fe2(PO4)3 and Na3+xFe2(PO4)3 compound. These results testify to the potential of monoclinic Na3Fe2(PO4)3 as a cathode material in sodium-ion batteries.
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高影响因子
RSC Advances
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2016
·Vol. 6
·期 19
·15577-15584
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IF 3.289
Haixia Xuan,Xi Chen,Yinghui Wu,Kena Song,Yuenan Li,Ruchuan Liu
The impact of the nanostructures of conjugated polymers on their electronic properties is significant. We notice that poly(3-hexylthiophene-2,5-diyl) (P3HT) can form nano-islands and nano-fibrils, and both of them show an similar single-layer thickness (∼1.5–1.6 nm) as evaluated by atomic force microscopy (AFM). The Raman spectra indicate the highest degree of chain planarity and crystallinity in the nano-islands. By using scanning Kelvin probe microscopy (SKPM) and electrostatic force microscopy (EFM), we image the surface potential at the nanometer scale and quantitatively estimate the charges on these nanostructures as modulated by light. Both results are consistent with each other: the surface potential increases on switching on the light, and the photo-induced charges are around 15–25% and positive. A similar amount of the photo-induced charges in both P3HT islands and fibril is consistent with the π–π stacking nature of these nanostructures. As P3HT is a hole-conducting molecule, positive charges are found easily injected into a single island by a positively biased EFM tip, and then the injected charges are able to propagate all over the island.
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高影响因子
BIOCATALYSIS AND BIOTRANSFORMATION
·
2016
·
IF 0.892
Wei Wei,Danping Qi,Mingming Diao,Lu Zhaoxin,Fengxia Lv,Haizhen Zhao
In this study, the synthesis of 3-O-β-D-galactopyranosyl-sn-glycerol (GG) was performed by the reverse hydrolysis of D-galactose and glycerol using β-galactosidase from Kluyveromyces lactis. Four process variables, reaction temperature (30.0–45.0 °C), reaction time (24–48 h), enzyme concentration (150.00–350.00 U/mL), and substrate molar ratio (glycerol:D-galactose, 7.5:12.5 mmol/mmol) were investigated and optimized via response surface methodology (RSM) for optimal GG synthesis. Both quadratic equations and the optimal reaction conditions were established. Results showed that the four variables, i.e., reaction temperature, reaction time, enzyme concentration, and substrate molar ratio had significant (p < 0.0001) effects on the synthesis of GG. The optimal reaction conditions were identified as 350.00 U/mL of β-galactosidase concentration and 8.65:1.00 of substrate molar concentration ratio (glycerol: D-galactose) at 39.8 °C and 48 h of reaction. Under these conditions, the GG concentration was 140.03 g/L and GG yield was 55.71%, which both were close to the predicted values (143.26 g/L and 56.73%). This finding proves the RSM to be a useful tool in optimizing process conditions for GG synthesis.
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高影响因子
RSC Advances
·
2017
·Vol. 7
·期 77
·48526-48536
·
IF 3.108
Qian Zeng,Jinwei Zhang,Hongye Cheng,Lifang Chen,Zhiwen Qi
Ionic liquids (IL) become more promising in industrial applications, especially in desulfurization processes. It is of great importance to investigate their corrosivity to steel and the effect of steel corrosion on desulfurization performance. In this work, the corrosion behavior of two typical metals, namely mild steel and stainless steel, in 1-butyl-3-methylimidazolium hydrogen sulfate ([BMIM]HSO4) IL systems for desulfurization application were investigated by weight loss and surface analyses. The model oil can inhibit the IL corrosivity, while the presence of water or H2O2 enhances the corrosion degree. The bonding information of [BMIM]HSO4 adsorbed on a steel surface was confirmed using ATR-FTIR. It was found that the IL film is mainly adsorbed on the metal surface by the interaction of the imidazolium group of the cation and HSO4− of the anion with the steel surface. From the ICP-MS and Raman analyses, the primary component of corrosion products is iron sulfate (ferric sulfate for mild steel and ferrous sulfate for stainless steel). Localized corrosion (pitting and/or intergranular corrosion) appears on steel surface from SEM observation, which could be a serious safety risk to the [BMIM]HSO4-based desulfurization systems for industrial application. The corrosion has a side effect on the desulfurization performance of [BMIM]HSO4.
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高影响因子
INTERNATIONAL JOURNAL OF ONCOLOGY
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2016
·Vol. 49
·期 2
·691-699
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IF 3.018
Zhen Zhang,Huiyun Wang,Qibao Wang,Maocai Yan,Huannan Wang,Caifeng Bi,Shanshan Sun,Yuhua Fan
Metal-containing compounds have been extensively studied for many years as potent proteasome inhibitors. The 20S proteasome, the main component of the ubiquitin proteasome pathway, is one of the excellent targets in anticancer drug development. We recently reported that several copper complexes were able to inhibit cancer-special proteasome and induce cell death in human cancer cells. However, the involved molecular mechanism is not known yet. We therefore synthesized three copper complexes and investigated their abilities on inhibiting proteasome activity and inducting apoptosis in human breast cancer cells. Furthermore, we employed molecular dockings to analyze the possible interaction between the synthetic copper complexes and the β5 subunit of proteasome which only reflects the chymotrypsin-like activity. Our results demonstrate that three Cu(II) complexes possess potent proteasome inhibition capability in a dose-dependent and time-dependent manner in MDA-MB-231 human breast cancer cells. They could bind to the β5 subunit of the 20S proteasome, which consequently cause deactivation of the proteasome and tumor cell death. The present study is significant for providing important theoretical basis for design and synthesis of anticancer drugs with low toxicity, high efficiency and high selectivity.
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PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2016
·
IF 4.179
Peizhu Zheng,Handi Yin,Jihua Zhao,Weiguo Shen
In order to clarify the nature of the inter-micellar interactions, we developed an approach to obtain the intermicellar interaction enthalpy through measuring the mixing heats of dodecyltrimethylammonium bromide (DTAB)/1-dodecyl-3-methylimidazolium bromide (C 12 mimBr) mixed micelles by using flow-mixing calorimetry . It was found that the inter-micellar interaction enthalpies for this system were negative, representing the attractive enthalpy interactions between the mixed micelle droplets. These results are contradictory to those reported in the literature and interpreted by the predominant attractive dehydration effect of counterion. Static light scattering experiment revealed that the repulsive nature of the interaction characterized by the Gibss free energy should be dominated by the entropy interaction.
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高影响因子
MOLECULES
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2016
·Vol. 21
·期 9
·1109
·
IF 2.465
Jianxia Sun,Zhouxiong Mei,Yajuan Tang,Lijun Ding,Guichuan Jiang,Chi Zhang,Aidong Sun,Weibin Bai
As an alternative preservation method to thermal treatment, ultrasound is a novel non-thermal processing technology that can significantly avoid undesirable nutritional changes. However, recently literature indicated that anthocyanin degradation occurred when high amplitude ultrasound was applied to juice. This work mainly studied the effect of ultrasound on the stability and antioxidant capacity of pelargonidin-3-glucoside (Pg-3-glu) and the correlation between anthocyanin degradation and •OH generation in a simulated system. Results indicated that the spectral intensities of Pg-3-glu decreased with increasing ultrasound power (200–500 W) and treatment time (0–60 min). The degradation trend was consistent with first-order reaction kinetics (R2> 0.9100). Further study showed that there was a good linear correlation between Pg-3-glu degradation and •OH production (R2= 0.8790), which indicated the important role of •OH in the degradation of anthocyanin during ultrasound exposure. Moreover, a decrease in the antioxidant activity of solution(s) containing Pg-3-glu as evaluated by the DPPH and FRAP methods was observed after ultrasound treatment.Keywords:ultrasound;cavitation;degradation;pelargonidin-3-glucoside;antioxidant activity;mechanism
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PubMed
高影响因子
ANALYTICAL CHEMISTRY
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2017
·
IF 6.32
Hong Cheng,Shi-Ying Li,Hao-Ran Zheng,Chu-Xin Li,Bo-Ru Xie,Ke-Wei Chen,Bin Li,Xian-Zheng Zhang
A novel single-molecular fluorescent probe was developed for spatiotemporal matrix metalloproteinase-2 (MMP-2) and caspase-3 imaging with distinct fluorescence signals. Due to the multi-Förster resonance energy transfer (FRET) processes, the probe could respond to MMP-2 and caspase-3 independently with high signal-to-noise ratio. Moreover, the overexpression of MMP-2 in cancer cell lines and the cisplatin induced cell apoptosis were spatiotemporal imaged with distinct fluorescence emissions. Because of the independent process of the probe for MMP-2 and caspase-3 imaging, the probe could meet the demands for precise disease diagnosis and cancer theranostic applications, which could extensively simplify the processes for precise cancer diagnosis and imaging.
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PubMed
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
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2017
·Vol. 23
·期 66
·16898-16905
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IF 5.317
Jing Zeng,Yang Yang,Shaobo Lai,Jianxing Huang,Yiyong Zhang,Jing Wang,Jinbao Zhao
Graphical Cathode for magnesium-ion batteries : An electrochemically desodiated phase NaV 2 (PO 4 ) 3 /C has been developed as a high-voltage cathode material (ca. 2.5 V vs. Mg 2+ /Mg) for rechargeable magnesium batteries, offering good cycle performance. The electrochemical reaction involves an intercalation mechanism and shows good reversibility. The lack of suitable high-voltage cathode materials has hindered the development of rechargeable magnesium batteries (RMBs). Here, mesoporous Na 3 V 2 (PO 4 ) 3 /C (NVP/C) spheres have been synthesized through a facile spray-drying–annealing method, and their electrochemically desodiated phase NaV 2 (PO 4 ) 3 /C (ED-NVP/C) has been investigated as an intercalation host for Mg 2+ ions. The obtained ED-NVP/C exhibits an average discharge voltage of around 2.5 V (vs. Mg 2+ /Mg), higher than those of most previously reported cathode materials. In addition, it can deliver an initial discharge capacity of 88.8 mA h g −1 at 20 mA g −1 , with good cycling stability. Ex situ X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results demonstrate that the electrochemical reaction is based on an intercalation mechanism and shows good reversibility. Galvanostatic intermittent titration technique (GITT) data have revealed that the intercalation process involves a two-phase transition. The reported ED-NVP/C cathode material with high working voltage offers promising potential for application in RMBs.
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PubMed
高影响因子
BIOCATALYSIS AND BIOTRANSFORMATION
·
2016
·
IF 0.892
Danping Qi,Wei Wei,Mingming Diao,Fengxia Lv,Zhaoxin Lu,Xiaomei Bie,Haizhen Zhao
Lipase-catalyzed synthesis of mono- and diesters of 3-O-β-D-galactopyranosyl-sn- glycerol (β-GG) with caproic acid was performed in acetone. The simultaneous production of 1(6’)-monoesters and 1,6’-diesters of β-GG was achieved in this reaction. In order to improve the yield of β-GG esters, four process parameters, enzyme concentration (15 ∼ 25 mg/mL), and substrate molar ratio (caproic acid: β-GG= 1.60 ∼ 2.00 mmol: 0.10 mmol), reaction temperature (40 ∼ 60 °C), and reaction time (8 ∼ 12 h), were optimized via response surface methodology (RSM) employing a three-level-four-variable central composite design. Results showed that enzyme concentration had the most significant (p < 0.0001) effect on the synthesis of β-GG esters. The optimal reaction conditions in acetone were given as follows: Novozyme435 concentration 18.65 mg/mL, molar rate of caproic acid to β-GG 19.46:1, reaction temperature 48 °C, and reaction time 9.83 h. The yield of β-GG esters reached 88.08% under above optimized conditions, which was very close to the predicted value 87.95%. The molar ratio of monoester to diesters was 0.39:0.61. β-GG esters with other fatty acyl chains were synthesized based on the optimized conditions. In vitro antitumor activity indicated that the antitumor activity of β-GG esters was dependent on the nature of fatty acids, such as the length of acyl chain, the degree of saturation, as well as the number of acyl chain.
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高影响因子
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
·
2017
·
IF 2.962
Weiwei Chen,Junde Li,Xiangnan Sun,Jun Min,Xiaoke Hu
A bacterial strain , CN-3, was isolated from petroleum-contaminated sediment in Bohai Bay, China. Morphological, physiological and phylogenetic analyses indicated that the strain belonged to the genus Dietzia . It was capable of utilizing a wide range of alkanes (C 14 –C 31 ), aromatic compounds and crude oil as the sole carbon and energy sources. The bacterium showed high degradation rate (>80%) of the saturated hydrocarbons of crude oil in the pH range of 6–9. The degradation rate was hardly affected at a NaCl concentration up to 85 g L −1 , indicating that the strain can tolerate high salinities . The real-time quantitative Polymerase Chain Reaction (PCR) results showed that the CYP153 genes could be significantly induced by C 14 , C 15 , C 16 , C 26 and pristane, whereas the transcription level of alk B gene was increased moderately with C 14 , C 15 , C 16 , C 26 and pristane induction condition. A high degradation extent, wide substrate range and facile conditions enhanced the potential for this bacterial strain to be used in the bioremediation of crude oil pollution.
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高影响因子
危险品化学品经营许可证（带存储）