Publications by authors named "Haiqiang Wang"

48 Publications

Medication Combination Prediction Using Temporal Attention Mechanism and Simple Graph Convolution.

IEEE J Biomed Health Inform 2021 May 21;PP. Epub 2021 May 21.

Medication combination prediction can be applied to the clinical treatment for critical patients with multi-morbidity. The suitable medication combination can help cure patients and keep the treatment medication safe. However, the complexity and uncertainty of clinical circumstances limit the predictive accuracy of medication combination. Thus, this paper proposes a new medication combination prediction model based on the temporal attention mechanism (TAM) and the simple graph convolution (SGC), named as TAMSGC. More specifically, the TAM can capture the temporal sequence information in the medical records, and the SGC is implemented to acquire the medication knowledge from the complicated medication combination. Experiments in a real dataset show that TAMSGC surpasses the baseline models on the predictive accuracy of medication combination.
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http://dx.doi.org/10.1109/JBHI.2021.3082548DOI Listing
May 2021

Effect of Cr doping in promoting the catalytic oxidation of dichloromethane (CHCl) over [email protected] catalysts.

J Hazard Mater 2021 Jul 5;413:125327. Epub 2021 Feb 5.

Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental Resources Science, Zhejiang University, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler Furnace Flue Gas Pollution Control, Hangzhou 310058, PR China.

A core-shell catalyst which consists of a CoO core and ZSM-5 shell, was prepared by microwave hydrothermal method and subjected for dichloromethane (DCM) oxidation. Chromium, cerium, niobium, and manganese species were separately introduced into the core-shell catalyst using the wet precipitation method and denoted as [email protected] (M = Cr, Ce, Nb, Mn). The catalytic activity of the [email protected] catalyst was significantly increased due to the interaction between CrO and CoO. The results of Raman spectra indicated the incorporation of chromium into the CoO lattice and revealed the existence of the interaction between CrO and CoO. The synergistic effect between CrO and CoO might be conducive to the generation of highly defective structure and increase the ratio of Co/Co of the sample, leading to its better oxygen mobility. The dechlorination ability of [email protected] was also promoted due to the enhanced mobility of lattice oxygen. Based on in situ DRIFT studies, a possible reaction route of CHCl oxidation over [email protected] catalyst was proposed.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125327DOI Listing
July 2021

Discovery and function exploration of microRNA-155 as a molecular biomarker for early detection of breast cancer.

Breast Cancer 2021 Jul 21;28(4):806-821. Epub 2021 Jan 21.

Department of General Surgery, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Kang Le Road No. 4, Zhangjiagang, 215600, Jiangsu, China.

Background: MicroRNA-155 (miR-155) may function as a diagnostic biomarker of breast cancer (BC). Nevertheless, the available evidence is controversial. Therefore, we performed this study to summarize the global predicting role of miR-155 for early detection of BC and preliminarily explore the functional roles of miR-155 in BC.

Methods: We first collected published studies and applied the bivariate meta-analysis model to generate the pooled diagnostic parameters of miR-155 in diagnosing BC such as sensitivity, specificity and area under curve (AUC). Then, we applied function enrichment and protein-protein interactions (PPI) analyses to explore the potential mechanisms of miR-155.

Results: A total of 21 studies were finally included. The results indicated that miR-155 allowed for the discrimination between BC patients and healthy controls with a sensitivity of 0.87 (95% CI 0.78-0.93), specificity of 0.82 (0.72-0.89), and AUC of 0.91 (0.88-0.93). In addition, the overall sensitivity, specificity and AUC for circulating miR-155 were 0.88 (0.76-0.95), 0.83 (0.72-0.90), and 0.92 (0.89-0.94), respectively. Function enrichment analysis revealed several vital ontologies terms and pathways associated with BC occurrence and development. Furthermore, in the PPI network, ten hub genes and two significant modules were identified to be involved in some important pathways associated with the pathogenesis of BC.

Conclusions: We demonstrated that miR-155 has great potential to facilitate accurate BC detection and may serve as a promising diagnostic biomarker for BC. However, well-designed cohort studies and biological experiments should be implemented to confirm the diagnostic value of miR-155 before it can be applied to routine clinical procedures.
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http://dx.doi.org/10.1007/s12282-021-01215-2DOI Listing
July 2021

Satisfied-User-Ratio Modeling for Compressed Video.

IEEE Trans Image Process 2020 Jan 17. Epub 2020 Jan 17.

With explosive increase of internet video services, perceptual modeling for video quality has attracted more attentions to provide high quality-of-experience (QoE) for end-users subject to bandwidth constraints, especially for compressed video quality. In this paper, a novel perceptual model for satisfied-user-ratio (SUR) on compressed video quality is proposed by exploiting compressed video bitrate changes and spatial-temporal statistical characteristics extracted from both uncompressed original video and reference video. In the proposed method, an efficient video feature set is explored and established to model SUR curves against bitrate variations by leveraging the Gaussian Processes Regression (GPR) framework. In particular, the proposed model is based on the recently released large-scale video quality dataset, VideoSet, and takes both spatial and temporal masking effects into consideration. To make it more practical, we further optimize the proposed method from three aspects including feature source simplification, computation complexity reduction and video codec adaption. Based on experimental results on VideoSet, the proposed method can accurately model SUR curves for various video contents and predict their required bitrates at given SUR values. Subjective experiments are conducted to further verify the generalization ability of the proposed SUR model.
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http://dx.doi.org/10.1109/TIP.2020.2965994DOI Listing
January 2020

Decorating g-CN with alkalinized TiC MXene for promoted photocatalytic CO reduction performance.

J Colloid Interface Sci 2020 Mar 23;564:406-417. Epub 2019 Dec 23.

Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental & Resources Science, Zhejiang University, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Hangzhou 311202, PR China.

Photocatalytic reduction of carbon dioxide (CO) under visible light irradiation for producing high-value fuel has attracted tremendous attention in recent years. In this study, titanium carbide MXene (TiC) was used as a noble metal-free co-catalyst by simply mixing graphitic carbon nitride (g-CN) and alkalized TiC. The carbon monoxide evolution rate of the optimized composite (5%TCOH-CN) from photocatalytic reduction of CO was 5.9 times higher than that of pure g-CN. Alkalized TiC was responsible for the superior photocatalytic activity due to its excellent electrical conductivity and large CO adsorption capacity. Furthermore, the separation of the photo-induced electron-hole pairs was greatly enhanced because of the large Fermi level difference between alkalized TiC and pure g-CN. This work demonstrates the potential of MXenes as noble metal-free co-catalyst for photocatalysis processes such as carbon dioxide reduction reaction and nitrogen reduction reaction.
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http://dx.doi.org/10.1016/j.jcis.2019.12.091DOI Listing
March 2020

Pharmacokinetics, tissue distribution and excretion of saponins after intravenous administration of ShenMai Injection in rats.

J Chromatogr B Analyt Technol Biomed Life Sci 2019 Oct 26;1128:121777. Epub 2019 Aug 26.

College of Pharmaceutical Sciences, Zhejiang University, Zijingang Campus, No. 866 Yuhangtang Road, Hangzhou 310058, PR China. Electronic address:

ShenMai Injection (SMI) is a traditional Chinese medicine that has been extensively applied in the treatment of coronary artery disease and tumor for many years. However, there is still lack of deep research on the behaviors of SMI in vivo. In this study, a reliable, specific, and sensitive method was developed for simultaneous determination of sixteen saponins found in SMI using liquid chromatography tandem mass spectrometry (LC-MS/MS). This method was successfully applied to investigate the pharmacokinetics, tissue distribution and excretion of sixteen active compounds after a single intravenous administration of SMI. These compounds included seven protopapaxdiol (PPD-type) ginsenosides (ginsenosides Rb, Rb, Rb, Rc, Rd, S-Rg, R-Rg), six protopapaxtriol (PPT-type) ginsenosides (notoginsenoside R, ginsenosides Re, Rf, Rg, S-Rg, R-Rg), one oleanolic acid type ginsenoside (ginsenoside Ro) and two ophiopogonins (ophiopogonin D (MD-D) and ophiopogonin D' (MD-D')). Connection of the C-20 hydroxyl group to the glycoside and the chiral configuration of C-20 might significantly impact the pharmacokinetic behaviors in vivo of ginsenosides, particularly PPD-type ginsenosides. PPD-type ginsenosides were usually eliminated slowly in serum and tissues, but S/R-Rg bearing a free hydroxyl group at C-20 exhibited quick elimination, and R-Rg underwent quicker elimination than S-Rg. The PPT-type ginsenosides, oleanolic acid type ginsenoside and ophiopogonins underwent a fast elimination from serum and tissues. There were 10 ginsenosides that could penetrate the blood-brain barrier. In contrast to other saponins, the distributions of S-Rg, R-Rg, S-Rg, R-Rg, MD-D and MD-D' in liver were higher than in kidney. Several PPD-type ginsenosides were found to have a long-term accumulation risk in some tissues, especially Rd in kidney. In the excretion study, Rg, S-Rg and MD-D were mainly excreted in a prototype and other saponins were mainly excreted in the form of metabolites. Prototypes of S-Rg, R-Rg, S-Rg, R-Rg, MD-D and MD-D' exhibited higher distribution in the liver than kidney, were excreted mainly in the feces, whereas prototypes of the remaining saponins were primarily excreted via urine. To best our knowledge, this is the first study to quantitatively evaluate the tissue distribution and excretion of SMI in rats. Our research provides novel insight into the behaviors in vivo of PPD-type ginsenosides and delivers valuable information for further drug development of SMI.
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http://dx.doi.org/10.1016/j.jchromb.2019.121777DOI Listing
October 2019

Synthesis of α-FeO/BiWO layered heterojunctions by in situ growth strategy with enhanced visible-light photocatalytic activity.

Sci Rep 2019 May 17;9(1):7551. Epub 2019 May 17.

Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, Department of Environmental Engineering, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, P.R. China.

Layered heterojunction structure with larger interface region for electron migration has attracted much attention in recent years. In this work, layered α-FeO/BiWO heterojunctions with strong interlayer interaction were successfully synthesized through a facile in situ growth method. The strong interaction between α-FeO and BiWO had resulted in excellent photoelectrochemical performance. It was found that such structure promoted the interfacial photogenerated charges separation according to EIS and Tafel analysis, except for the expansion of visible-light absorption range. PL and TRPL characterizations further demonstrated that the recombination ratio of photoexcited electron-hole pairs was greatly reduced. The toluene photocatalytic degradation tests had showed that α-FeO/BiWO composites exhibited much well activity under visible-light irradiation. Especially, 4%-FeO/BiWO sample displayed the highest photocatalytic activity, which was around 3 and 4 times higher than that of pure BiWO and α-FeO. Based on ESR results and free radical trapping experiments, hydroxyl radicals (·OH) and holes (h) were regarded as the main active species. The establishment of FeO/BiWO with layered heterojunctions could provide new insights into the construction of novel photocatalysts.
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http://dx.doi.org/10.1038/s41598-019-43917-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6525269PMC
May 2019

Deep Oxidation of NO by a Hybrid System of Plasma-N-Type Semiconductors: High-Energy Electron-Activated "Pseudo Photocatalysis" Behavior.

Environ Sci Technol 2018 08 18;52(15):8568-8577. Epub 2018 Jul 18.

Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental & Resources Science , Zhejiang University , Hangzhou 310058 , P.R. China.

A "pseudo photocatalysis" process, being initiated between plasma and N-type semiconductors in the absence of light, was investigated for NO removal for the first time via dynamic probing of reaction processes by FT-IR spectra. It was demonstrated that N-type semiconductor catalysts could be activated to produce electron-hole (e-h) pairs by the collision of high-energy electrons (e*) from plasma. Due to the synergy of plasma and N-type semiconductors, major changes were noted in the conversion pathways and products. NO can be directly converted to NO and NO instead of toxic NO, owing to the formation of O and ·OH present in catalysts. New species like O or ·O may be generated from the interaction between catalyst-induced species and radicals in plasma at a higher SIE, leading to deep oxidation of existing NO to NO. Experiments with added trapping agents confirmed the contribution of e and h from catalysts. A series of possible reactions were proposed to describe reaction pathways and the mechanism of this synergistic effect. We established a novel system and realized an e*-activated "pseudo photocatalysis" behavior, facilitating the deep degradation of NO. We expect that this new strategy would provide a new idea for in-depth analysis of plasma-activated catalysis phenomenon.
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http://dx.doi.org/10.1021/acs.est.8b00655DOI Listing
August 2018

Many-body interactions between charged particles in a polymer solution: the protein regime.

Soft Matter 2018 May;14(20):4064-4073

School of Physical, Environmental and Mathematical Sciences University College, University of New South Wales, ADFA Canberra ACT 2600, Australia.

We study the phase behavior of charged particles in electrolyte solutions wherein non-adsorbing polymers are added to provide an attractive depletion interaction. The polymer has a radius of gyration similar to that of the particle radius, which causes significant many-body effects in the effective polymer mediated interaction between particles. We use a recently developed analytical theory, which gives a closed expression for the full depletion interaction, accounting for all orders of many-body terms in the potential of mean force. We compare with simulations of an explicit polymer model and show that the potential of mean force provides an accurate and computationally efficient description for the charged particle/polymer mixture, over a range of electrolyte concentrations. Furthermore, we demonstrate that the usual pair potential approach is highly inaccurate for these systems. A simple simulation method is used to estimate the limits of stability of the mixture. The pair approximation is shown to predict a much greater region of instability compared with the many-body treatment, due to its overestimation of the polymer depletion effect.
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http://dx.doi.org/10.1039/c8sm00471dDOI Listing
May 2018

Uniformly active phase loaded selective catalytic reduction catalysts (VO/TNTs) with superior alkaline resistance performance.

J Hazard Mater 2017 Feb 9;324(Pt B):507-515. Epub 2016 Nov 9.

Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental & Resources Science, Zhejiang University, 310058 Hangzhou, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Hangzhou 310027, PR China. Electronic address:

In this work, protonated titanate nanotubes was performed as a potential useful support and different vanadium precursors (NHVO and VOSO) were used to synthesize deNO catalysts. The results showed that VOSO exhibited better synergistic effect with titanate nanotubes than NHVO, which was caused by the ion-exchange reaction. Then high loading content of vanadium, uniformly active phase distribution, better dispersion of vanadium, more acid sites, better V/V redox cycles and superior oxygen mobility were achieved. Besides, VOSO-based titanate nanotubes catalysts also showed enhanced alkaline resistance than particles (P25) based catalysts. It was strongly associated with its abundant acid sites, large surface area, flexible redox cycles and oxygen transfer ability. For the loading on protonated titanate nanotubes, active metal with cation groups was better precursors than anion ones. VO/TNTs catalyst was a promising substitute for the commercial vanadium catalysts and the work conducted herein provided a useful idea to design uniformly active phase loaded catalyst.
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http://dx.doi.org/10.1016/j.jhazmat.2016.11.019DOI Listing
February 2017

Rapid discovery and identification of anti-inflammatory constituents from traditional Chinese medicine formula by activity index, LC-MS, and NMR.

Sci Rep 2016 08 8;6:31000. Epub 2016 Aug 8.

Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, P.R. China.

The traditional activity-guided approach has the shortcoming of low accuracy and efficiency in discovering active compounds from TCM. In this work, an approach was developed by integrating activity index (AI), liquid chromatography - mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR) to rapidly predict and identify the potential active constituents from TCM. This approach was used to discover and identify the anti-inflammatory constituents from a TCM formula, Gui-Zhi-Jia-Shao-Yao-Tang (GZJSYT). The AI results indicated that, among the 903 constituents detected in GZJSYT by LC-MS, 61 constituents with higher AI values were very likely to have anti-inflammatory activities. And eight potential active constituents of them were isolated and validated to have significant inhibitory effects against NO production on LPS-induced RAW 264.7 cell model. Among them, glycyrrhisoflavone (836), glisoflavanone (893) and isoangustone A (902) were reported to have anti-inflammatory effects for the first time. The proposed approach could be generally applicable for rapid and high efficient discovery of anti-inflammatory constituents from other TCM formulae or natural products.
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http://dx.doi.org/10.1038/srep31000DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4976346PMC
August 2016

Quantitative transfer of Salmonella Typhimurium LT2 during mechanical slicing of tomatoes as impacted by multiple processing variables.

Int J Food Microbiol 2016 Oct 28;234:76-82. Epub 2016 Jun 28.

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824, USA. Electronic address:

Slicing of fresh produce can readily lead to pathogen cross-contamination with pre-sliced tomatoes having been linked to multistate outbreaks of salmonellosis in the United States. This study aimed to assess the impact of multiple processing variables on quantitative transfer of Salmonella during simulated commercial slicing of tomatoes. One red round tomato was inoculated with Salmonella Typhimurium LT2 at ~5logCFU/g and sliced using a manual or electric slicer, followed by 20 uninoculated tomatoes. Thereafter, the distribution of Salmonella on inoculated and uninoculated tomato slices was evaluated along with the transfer of Salmonella from different parts of the slicer. The impact of multiple processing variables including post-contamination hold time (0 and 30min), tomato wetness (dry and wet), processing room temperature (23, 10 and 4°C), slice thickness (0.48, 0.64, and 0.95cm), tomato variety (Torero, Rebelski, and Bigdena) and pre-wash treatment (no wash, tap water, and chlorine) was also investigated. The data were fitted to a two-parameter exponential decay model (Y=A⋅exp(BX)) with the percentage of Salmonella transferred to 20 uninoculated tomatoes then calculated. Salmonella populations on nine inoculated tomato slices ranged from 4.6±0.2 to 5.5±0.3logCFU/g, with higher populations on slices from the blossom and stem scar ends. However, Salmonella transfer to the previously uninoculated slices was similar (P>0.05), ranging from 2.1±0.2 to 3.4±0.2logCFU/g. Significantly fewer salmonellae transferred from the blade (3.4±0.4 log CFU, P≤0.05) than from the back and bottom plates (4.7±0.3 log CFU) or the whole manual slicer (5.2±0.2 log CFU) to the 20 uninoculated tomatoes. However, the blade was the primary contributor to Salmonella transfer for the electric slicer. Post-contamination hold time, processing temperature and tomato slice thickness did not significantly impact (P>0.05) the Salmonella transfer rate (parameter B) or the overall percentage of cells transferred. A significantly lower (P≤0.05) transfer rate (-0.028±0.002) was observed for wet as compared to dry tomatoes (-0.051±0.002), with a significantly higher (P≤0.05) percentage (12.2±2.4%) of Salmonella transferred to wet as opposed to dry tomatoes (1.1±0.5%). Tomato variety also impacted Salmonella transfer with significantly lower (P≤0.05) transfer rates and Salmonella transfer percentages seen for Rebelski and Bigdena than Torero. These findings will provide practical guidelines for the fresh-cut tomato industry and will also be useful in developing science-based transfer models for risk assessments.
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http://dx.doi.org/10.1016/j.ijfoodmicro.2016.06.035DOI Listing
October 2016

Density functional theory of equilibrium random copolymers: application to surface adsorption of aggregating peptides.

J Phys Condens Matter 2016 06 26;28(24):244011. Epub 2016 Apr 26.

School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Canberra at the Australian Defence Force Academy, Canberra ACT 2600, Australia.

We generalize a recently developed polymer density functional theory (PDFT) for polydisperse polymer fluids to the case of equilibrium random copolymers. We show that the generalization of the PDFT to these systems allows us to obtain a remarkable simplification compared to the monodispersed polymers. The theory is used to treat a model for protein aggregation into linear filaments in the presence of surfaces. Here we show that, for attractive surfaces, there is evidence of significant enhancement of protein aggregation. This behaviour is a consequence of a surface phase transition, which has been shown to occur with ideal equilibrium polymers in the presence of sufficiently attractive surfaces. For excluding monomers, this transition is suppressed, though an echo of the underlying ideal transition is present in the sudden change in the excess adsorption.
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http://dx.doi.org/10.1088/0953-8984/28/24/244011DOI Listing
June 2016

Numerical evaluation of the effectiveness of NO2 and N2O5 generation during the NO ozonation process.

J Environ Sci (China) 2016 Mar 21;41:51-58. Epub 2015 Jul 21.

Department of Environment Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Engineering Research Center of Industrial Boiler, Furnace Flue Gas Pollution Control, Hangzhou 310058, China. Electronic address:

Wet scrubbing combined with ozone oxidation has become a promising technology for simultaneous removal of SO2 and NOx in exhaust gas. In this paper, a new 20-species, 76-step detailed kinetic mechanism was proposed between O3 and NOx. The concentration of N2O5 was measured using an in-situ IR spectrometer. The numerical evaluation results kept good pace with both the public experiment results and our experiment results. Key reaction parameters for the generation of NO2 and N2O5 during the NO ozonation process were investigated by a numerical simulation method. The effect of temperature on producing NO2 was found to be negligible. To produce NO2, the optimal residence time was 1.25sec and the molar ratio of O3/NO about 1. For the generation of N2O5, the residence time should be about 8sec while the temperature of the exhaust gas should be strictly controlled and the molar ratio of O3/NO about 1.75. This study provided detailed investigations on the reaction parameters of ozonation of NOx by a numerical simulation method, and the results obtained should be helpful for the design and optimization of ozone oxidation combined with the wet flue gas desulfurization methods (WFGD) method for the removal of NOx.
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http://dx.doi.org/10.1016/j.jes.2015.05.015DOI Listing
March 2016

Discriminative Feature Extraction via Multivariate Linear Regression for SSVEP-Based BCI.

IEEE Trans Neural Syst Rehabil Eng 2016 05 21;24(5):532-41. Epub 2016 Jan 21.

Many of the most widely accepted methods for reliable detection of steady-state visual evoked potentials (SSVEPs) in the electroencephalogram (EEG) utilize canonical correlation analysis (CCA). CCA uses pure sine and cosine reference templates with frequencies corresponding to the visual stimulation frequencies. These generic reference templates may not optimally reflect the natural SSVEP features obscured by the background EEG. This paper introduces a new approach that utilizes spatio-temporal feature extraction with multivariate linear regression (MLR) to learn discriminative SSVEP features for improving the detection accuracy. MLR is implemented on dimensionality-reduced EEG training data and a constructed label matrix to find optimally discriminative subspaces. Experimental results show that the proposed MLR method significantly outperforms CCA as well as several other competing methods for SSVEP detection, especially for time windows shorter than 1 second. This demonstrates that the MLR method is a promising new approach for achieving improved real-time performance of SSVEP-BCIs.
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http://dx.doi.org/10.1109/TNSRE.2016.2519350DOI Listing
May 2016

Enhanced CO2 adsorptive performance of PEI/SBA-15 adsorbent using phosphate ester based surfactants as additives.

J Environ Sci (China) 2015 Dec 6;38:1-7. Epub 2015 Aug 6.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Engineering Research Center of Industrial Boiler and Furnace Flue Gas Pollution Control, Hangzhou 310058, China.

In this study, a series of polyetherimide/SBA-15: 2-D hexagonal P6mm, Santa Barbara USA (PEI/SBA-15) adsorbents modified by phosphoric ester based surfactants (including tri(2-ethylhexyl) phosphate (TEP), bis(2-ethylhexyl) phosphate (BEP) and trimethyl phosphonoacetate (TMPA)) were prepared for CO2 adsorption. Experimental results indicated that the addition of TEP and BEP had positive effects on CO2 adsorption capacity over PEI/SBA-15. In particular, the CO2 adsorption amount could be improved by around 20% for 45PEI-5TEP/SBA-15 compared to the additive-free adsorbent. This could be attributed to the decrease of CO2 diffusion resistance in the PEI bulk network due to the interactions between TEP and loaded PEI molecules, which was further confirmed by adsorption kinetics results. In addition, it was also found that the cyclic performance of the TEP-modified adsorbent was better than the surfactant-free one. This could be due to two main reasons, based on the results of in situ DRIFT and TG-DSC tests. First and more importantly, adsorbed CO2 species could be desorbed more rapidly over TEP-modified adsorbent during the thermal desorption process. Furthermore, the enhanced thermal stability after TEP addition ensured lower degradation of amine groups during adsorption/desorption cycles.
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http://dx.doi.org/10.1016/j.jes.2015.04.025DOI Listing
December 2015

Catalyst performance and mechanism of catalytic combustion of dichloromethane (CH2Cl2) over Ce doped TiO2.

J Colloid Interface Sci 2016 Feb 26;463:233-41. Epub 2015 Oct 26.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Hangzhou 310058, PR China.

TiO2 and Ce/TiO2 were synthesized and subsequently used for the catalytic combustion of DCM. TiO2 had abundant Lewis acid sites and was responsible for the adsorption and the rupture of C-Cl bonds. However, TiO2 tended to be inactivated because of chloride poisoning due to the adsorption and accumulation of Cl species over the surface. While, Ce/TiO2 obtained total oxidation of CH2Cl2 at 335°C and exhibited stable DCM removal activity on 100h long-time stability tests at 330°C without any catalyst deactivation. The doped cerium generated Ce(3+) chemical states and surface active oxygen, and therefore played important roles from two aspects as follows. First of all, the poisoning of Cl for Ce/TiO2 was inhibited to some extent by CeO2 due to the rapid removal of Cl on the surface of CeO2, which has been verified by NH3-IR characterization. In the other hand, CeO2 enhanced the further deep oxidation of C-H from byproducts and retained the certain oxidation of CO to CO2. Based on the DRIFT characterization and the catalysts activity tests, a two-step reaction pathway for the catalytic combustion of DCM on Ce/TiO2 catalyst was proposed.
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http://dx.doi.org/10.1016/j.jcis.2015.10.061DOI Listing
February 2016

Binding of pixantrone to DNA at CpA dinucleotide sequences and bulge structures.

Org Biomol Chem 2015 Jun;13(21):5972-82

School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Australian Defence Force Academy, Northcott Drive, Campbell, ACT 2600, Australia.

The binding of the anti-cancer drug pixantrone to three oligonucleotide sequences, d(TCATATGA)2, d(CCGAGAATTCCGG)2 {double bulge = DB} and the non-self complementary d(TACGATGAGTA) : d(TACCATCGTA) {single bulge = SB}, has been studied by NMR spectroscopy and molecular modelling. The upfield shifts observed for the aromatic resonances of pixantrone upon addition of the drug to each oligonucleotide confirmed the drug bound by intercalation. For the duplex sequence d(TCATATGA)2, NOEs were observed from the pixantrone aromatic H7/8 and aliphatic Ha/Hb protons to the H6/H8 and H1' protons of the C2, A3, T6 and G7 nucleotides, demonstrating that pixantrone preferentially binds at the symmetric CpA sites. However, weaker NOEs observed to various protons from the T4 and A5 residues indicated alternative minor binding sites. NOEs from the H7/H8 and Ha/Hb protons to both major (H6/H8) and minor groove (H1') protons indicated approximately equal proportions of intercalation was from the major and minor groove at the CpA sites. Intermolecular NOEs were observed between the H7/H8 and H4 protons of pixantrone and the A4H1' and G3H1' protons of the oligonucleotide that contains two symmetrically related bulge sites (DB), indicative of binding at the adenine bulge sites. For the oligonucleotide that only contains a single bulge site (SB), NOEs were observed from pixantrone protons to the SB G7H1', A8H1' and G9H1' protons, confirming that the drug bound selectively at the adenine bulge site. A molecular model of pixantrone-bound SB could be constructed with the drug bound from the minor groove at the A8pG9 site that was consistent with the observed NMR data. The results demonstrate that pixantrone preferentially intercalates at adenine bulge sites, compared to duplex DNA, and predominantly from the minor groove.
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http://dx.doi.org/10.1039/c5ob00526dDOI Listing
June 2015

Efficacy of various sanitizers against Salmonella during simulated commercial packing of tomatoes.

J Food Prot 2014 Nov;77(11):1868-75

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824, USA.

Chemical sanitizers are usually added to dump tank water to minimize cross-contamination during tomato packing. However, the efficacy of sanitizers continues to be questioned. This study assessed the ability of six commonly used sanitizers (40 ppm of peroxyacetic acid, 40 ppm of mixed peracid, 40 ppm of available chlorine alone or acidified to pH 6.0 with citric acid or T-128, and electrolyzed water containing 40 ppm of available chlorine at pH 6.7) to reduce Salmonella on tomatoes, in wash water, and on equipment surfaces using a pilot-scale processing line. Red round tomatoes (11.3 kg) were dip inoculated to contain Salmonella at ∼6 log CFU/g, air dried for 2 h, treated for 2 min in a 3.3-m-long dump tank and then dried on a roller conveyor, with sanitizer-free water serving as the control. Tomato and water samples were collected at 15-s intervals during washing with additional dump tank, water tank, and roller conveyor surface samples collected after washing. All samples were appropriately neutralized, diluted, and surface plated on Trypticase soy agar containing 0.6% yeast extract, 0.05% ferric ammonium citrate, and 0.03% sodium thiosulfate with or without membrane filtration to enumerate Salmonella. All six sanitizer treatments were more efficacious than the water control (P ≤ 0.05), with chlorine plus citric acid yielding the greatest Salmonella reduction on tomatoes (3.1 log CFU/g). After processing, all sanitizer wash solutions contained significantly lower (P ≤ 0.05) levels of Salmonella than the water control (3.0 log CFU/ml). The four chlorine-based sanitizer treatments yielded significantly lower Salmonella populations (P ≤ 0.05) in the wash solution compared with peroxyacetic acid and mixed peracid. After processing with sanitizers, Salmonella populations decreased to nondetectable levels (<0.2 log CFU/100 cm(2) ) on the equipment surfaces.
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http://dx.doi.org/10.4315/0362-028X.JFP-14-213DOI Listing
November 2014

Mercury re-emission in flue gas multipollutants simultaneous absorption system.

Environ Sci Technol 2014 Dec 11;48(23):14025-30. Epub 2014 Nov 11.

Department of Environmental Engineering, Zhejiang University , Hangzhou 310058, P. R. China.

Recently, simultaneous removal of SO2, NOx and oxidized mercury in wet flue gas desulfurization (WFGD) scrubber has become a research focus. Mercury re-emission in traditional WFGD system has been widely reported due to the reduction of oxidized mercury by sulfite ions. However, in multipollutants simultaneous absorption system, the formation of a large quantity of nitrate and nitrite ions as NOx absorption might also affect the reduction of oxidized mercury in the aqueous absorbent. As such, this paper studied the effects of nitrate and nitrite ions on mercury re-emission and its related mechanism. Experimental results revealed that the nitrate ions had neglected effect on mercury re-emission while the nitrite ions could greatly change the mercury re-emission behaviors. The nitrite ions could initially improve the Hg(0)-emission through the decomposition of HgSO3NO2(-), but with a further increase in the concentration, they would then inhibit the reduction of bivalent mercury owing to the formation of Hg-nitrite complex [Hg(NO2)x(2-x)]. In addition, the subsequent addition of Cl(-) could further suppress the Hg(0) emission, where the formation of a stable Hg-SO3-NO2-Cl complex was assumed to be the main reason for such strong inhibition effect.
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http://dx.doi.org/10.1021/es503837wDOI Listing
December 2014

Evaluation of fungicides enestroburin and SYP1620 on their inhibitory activities to fungi and oomycetes and systemic translocation in plants.

Pestic Biochem Physiol 2014 Jun 4;112:19-25. Epub 2014 Jun 4.

Department of Plant Pathology, China Agricultural University, Beijing, China. Electronic address:

Enestroburin and SYP1620 are newly developed strobilurin chemicals carrying fungicidal activity and need to be fully characterized in activities of anti-oomycete or anti-fungi, disease prevention and systemic translocation in planta. Their inhibitory activities were examined by amending the chemical in agar media, on which selected plant pathogens were grown and mycelial growth were measured. Effective concentrations for 50% inhibition (EC50) of mycelial growth were calculated to determine the level of fungicide sensitivity of the pathogen. Azoxystrobin was used as control. To examine the prevention and systemic translocation in plants, the fungicides were either sprayed on wheat leaves or dipped on wheat roots, which then were detected using high performance liquid chromatography. All the three fungicides inhibited mycelial growth of Sphacelotheca reiliana, Phytophthora infestans, Peronophythora litchi, and Magnaporthe oryzae, with EC50 values ranging from 0.02 to 2.84μg/ml; EC50 of SYP1620 was significantly lower than that of azoxystrobin and enestroburin on Valsa mali, Gaeumannomyces graminis, Alternaria solani, and Colletotrichun orbiculare. The three QoI fungicides showed strong inhibitory activities on spore germination against the 13 pathogens tested and were highly effective on biotrophic pathogens tested. Enestroburin and SYP1620 penetrated and spread in wheat leaves, but the penetration and translocation levels were lower compared to azoxystrobin. The three fungicides were all rapidly taken up by wheat roots and transported upwards, with greater fungicide concentrations in roots than in stems and leaves. The results indicate that enestroburin and SYP1620 are systemic fungicides that inhibit a broad spectrum of fungi and oomycetes.
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http://dx.doi.org/10.1016/j.pestbp.2014.05.004DOI Listing
June 2014

Exact evaluation of the depletion force between nanospheres in a polydisperse polymer fluid under Θ conditions.

J Chem Phys 2014 May;140(19):194903

Theoretical Chemistry, Chemical Centre, Lund University, P.O. Box 124, S-221 00 Lund, Sweden.

We analyze a system consisting of two spherical particles immersed in a polydispersed polymer solution under theta conditions. An exact theory is developed to describe the potential of mean force between the spheres for the case where the polymer molecular weight dispersity is described by the Schulz-Flory distribution. Exact results can be derived for the protein regime, where the sphere radius (R(s)) is small compared to the average radius of gyration of the polymer (R(g)). Numerical results are relatively easily obtained in the cases where the sphere radius is increased. We find that even when q = R(g)/R(s) ⪆ 10, then the use of a monopole expansion for the polymer end-point distribution about the spheres is sufficient. For even larger spheres q ≈ 1, accuracy is maintained by including a dipolar correction. The implications of these findings on generating a full many-body effective interaction for a collection of N spheres imbedded in the polymer solution are discussed.
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http://dx.doi.org/10.1063/1.4874977DOI Listing
May 2014

Mechanisms and reaction pathways for simultaneous oxidation of NOx and SO₂ by ozone determined by in situ IR measurements.

J Hazard Mater 2014 Jun 21;274:376-83. Epub 2014 Apr 21.

Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China. Electronic address:

Ozone (O3) oxidation combined with wet scrubbing is a promising method for the simultaneous removal of SO2 and NOx in flue gas. In this study, the O3 oxidation processes of NO and SO2, as well as their coexistence, were investigated using an in situ IR spectrometer. Experimental results showed that the O3 concentration and the reaction temperature played critical roles in the O3 oxidation process of NO. Around 80°C, when inlet molar ratio of O3/NO was less than 1, NO was mainly oxidized to NO2, while when the ratio was greater than 1, NO would be further oxidized to NO3, N2O5, and HNO3. NO3 was the key intermediate product for the formation of N2O5 and HNO3. However, the subsequent reactions of NO3 were temperature dependence. With the increase of reaction temperature above 100°C, the concentration of NO2 increased whereas the concentrations of N2O5 and HNO3 decreased. The oxidation of SO2 by O3 was negligible and SO2 had little influence on the oxidation of NO in the simultaneous oxidation of NO and SO2. Finally, based on the in situ IR results, the oxidation mechanism is discussed and the reaction pathways are proposed.
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http://dx.doi.org/10.1016/j.jhazmat.2014.04.027DOI Listing
June 2014

Salmonella transfer during pilot plant scale washing and roller conveying of tomatoes.

J Food Prot 2014 Mar;77(3):380-7

Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824, USA.

Salmonella transfer during washing and roller conveying of inoculated tomatoes was quantified using a pilot scale tomato packing line equipped with plastic, foam, or brush rollers. Red round tomatoes (2.3 kg) were dip inoculated with Salmonella enterica serovar Typhimurium LT2 (avirulent) (4 log CFU/g), air dried for 2 h, and then washed in sanitizer-free water for 2 min. Inoculated tomatoes were then passed single file over a 1.5-m conveyor equipped with plastic, foam, or brush rollers followed by 25 previously washed uninoculated tomatoes. Tomato samples were collected after 2 min of both washing and roller conveying, with all 25 uninoculated tomatoes collected individually after conveying. Roller surface samples were collected before and after conveying the uninoculated tomatoes. Both tomato and surface samples were quantitatively examined for Salmonella by direct plating or membrane filtration using xylose lysine Tergitol 4 agar. Regardless of the roller type, Salmonella populations on inoculated tomatoes did not significantly (P < 0.05) decrease during contact with the roller conveyors. After conveying uninoculated tomatoes over contaminated foam rollers, 96% of the 25 tomatoes were cross-contaminated with Salmonella at >100 CFU per tomato. With plastic rollers, 24 and 76% of tomatoes were cross-contaminated with Salmonella at 10 to 100 and 1 to 10 CFU per tomato, respectively. In contrast, only 8% of 25 tomatoes were cross-contaminated with brush rollers with Salmonella populations of 1 to 10 CFU per tomato. Overall, cross-contamination was greatest with foam, followed by plastic and brush rollers (P < 0.05). Adding peroxyacetic acid or chlorine to the wash water significantly decreased cross-contamination during tomato conveying, with chlorine less effective in controlling Salmonella on foam compared with plastic and brush rollers.
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http://dx.doi.org/10.4315/0362-028X.JFP-13-314DOI Listing
March 2014

One-step synthesis of Cl(-)-doped Pt(IV)/Bi2WO6 with advanced visible-light photocatalytic activity for toluene degradation in air.

J Colloid Interface Sci 2013 Dec 17;412:31-8. Epub 2013 Sep 17.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Hangzhou 311202, PR China.

In this study, Cl(-) doped Pt(IV)/Bi2WO6 photocatalyst was successfully synthesized via a one-step hydrothermal route by adding H2PtCl6 immediately in the reaction system. X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption isotherms and photoluminescence spectra (PL) were utilized to analyze the morphology, chemical states, surface area and optical properties of as-prepared catalysts. The addition of H2PtCl6 to the reaction system inhibited the growth of Bi2WO6 square nanoplates but facilitated the generation of irregular Bi2WO6 nanosheets with enlarged surface area and extended visible light absorption. In the resulted sample, it was observed that Pt(IV) was uniformly dispersed on the surface of Bi2WO6 irregular nanosheets and Cl(-) other than that from PtCl4 was doped into the sample by forming ionic bond with [Bi2O2](2+). Compared with pure Bi2WO6 nanosheets, Cl(-) doped Pt(IV)/Bi2WO6 showed enhanced activity in photocatalytic decomposition of toluene under visible light irradiation (420 nm<λ<780 nm). The catalyst with theoretical 1.0 wt.% Pt showed the best performance, which degraded 25 ppm toluene thoroughly in 35 min. Finally, the forming mechanism of Cl(-) doped Pt(IV)/Bi2WO6 in the one-step hydrothermal process was proposed.
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http://dx.doi.org/10.1016/j.jcis.2013.09.004DOI Listing
December 2013

Ceria supported on sulfated zirconia as a superacid catalyst for selective catalytic reduction of NO with NH3.

J Colloid Interface Sci 2013 Mar 9;394:515-21. Epub 2013 Jan 9.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.

In this paper, ceria supported on sulfated zirconia (CeSZ) as a superacid catalyst was synthesized and the resulted performances for selective catalytic reduction (SCR) of NO with NH(3) were investigated. Experimental results revealed that the sulfation of zirconia supports could greatly improve the SCR activity of the catalysts. Among the tested samples, the CeSZ catalyst with Ce/Zr mole ratio at 0.095 possessed the highest NO conversion (i.e., 98.6% at ca. 420 °C and 180,000 h(-1)). The sulfation had led to a formation of pure tetragonal phase of ZrO(2), a well dispersion of CeO(2), abundant stable superacid sites, increasing surface area and enrichment of Ce(3+) on the surface, all of which were responsible for its excellent performance in SCR of NO with NH(3).
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http://dx.doi.org/10.1016/j.jcis.2012.12.034DOI Listing
March 2013

Mesoporous metal and metal alloy particles synthesized by aerosol-assisted confined growth of nanocrystals.

Angew Chem Int Ed Engl 2012 Oct 23;51(42):10546-50. Epub 2012 Sep 23.

Department of Chemical & Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA.

From droplets to "spheres": A platform technology enables the rapid and continuous synthesis of mesoporous metal and metal alloy particles (see picture). The confined growth of nanocrystals in aerosol droplets leads to the formation of these particles with defined composition.
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http://dx.doi.org/10.1002/anie.201204289DOI Listing
October 2012

Polyethyleneimine functionalized protonated titanate nanotubes as superior carbon dioxide adsorbents.

J Colloid Interface Sci 2012 Nov 24;386(1):392-7. Epub 2012 Jul 24.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, PR China.

In this paper, protonated titanate nanotubes (PTNTs) were modified with polyethyleneimine (PEI) by wet impregnation method for CO(2) adsorption. Their micro-morphology and structural properties were characterized by a range of analytical techniques, including XRD, TEM, SEM, N(2) adsorption etc. Experimental results revealed that the functionalized PTNTs with 50 wt.% PEI loaded exhibited a high CO(2) adsorption capacity of 130.8 mg/g-sorbent at 100°C. Only a minor loss of its capacity was observed after five consecutive adsorption-desorption runs. The PEI was existed both in the internal and external mesoporous pores of PTNTs via chemical combination between amino group and enriched protons, which accounted for their good thermal stability at elevated temperatures. The results present herein imply that the PEI modified PTNTs could be appealing materials for capturing CO(2) from power plant flue gas.
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http://dx.doi.org/10.1016/j.jcis.2012.07.048DOI Listing
November 2012

Effect of pH value on the microstructure and deNO(x) catalytic performance of titanate nanotubes loaded CeO2.

J Colloid Interface Sci 2012 Jul 21;377(1):131-6. Epub 2012 Mar 21.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.

The relationship between catalytic performance and pH value of post-treatment of the catalyst supports-titanate materials was investigated and discussed. Three types of titanate nanotubes (TNTs) that are acidic TNTs (TNTs-1.6, pH value at 1.6), neutral TNTs (TNTs-7), and alkaline TNTs (TNTs-12) were synthesized by hydrothermal method with the controlled washing pH value and then were used as the catalyst supports for ceria. These titanate-supported ceria catalysts showed extremely different performance for the selective catalytic reduction in NO. The pH value had a notable effect on the structure and composition of titanate nanotubes and further affected the state and redox property of cerium oxides. The structure of TNTs-1.6, TNTs-7, and TNTs-12 were identified as anatase-like structure, protonated titanate (H(2)Ti(3)O(7)), and Na-containing titanate, respectively. Indeed, the residual sodium (TNTs-12) was harmful to ceria, but the presence of water in the interlayer (TNTs-7) was beneficial to the stability of nanotube structure. Therefore, TNTs-7 doped ceria showed the best SCR activity among these tested samples.
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http://dx.doi.org/10.1016/j.jcis.2012.03.040DOI Listing
July 2012

A theoretic insight into the catalytic activity promotion of CeO2 surfaces by Mn doping.

Phys Chem Chem Phys 2012 Apr 20;14(16):5769-77. Epub 2012 Mar 20.

Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.

In this paper, we investigated the primary reduction and oxygen replenishing processes over Mn substitutionally doped CeO(2)(111) surfaces by density functional theory with the on-site Coulomb correction (DFT + U). The results indicated that Mn doping could make the surface much more reducible and the adsorbed O(2) could be effectively activated to form superoxo (O(2)(-)) and/or peroxo species (O(2)(2-)). The Mn doping induced the Mn 3d-O 2p gap state instead of Ce 4f acting as an electrons acceptor and donor during the first oxygen vacancy formation and O(2) replenishing, which helped to lower the formation energy of the first and second oxygen vacancies to -0.46 eV and 1.40 eV, respectively. In contrast, the formation energy of a single oxygen vacancy in the pure ceria surface was 2.08 eV and only peroxo species were identified as the O(2) molecule adsorbed. Our work provides a theoretical and electronic insight into the catalytic redox processes of Mn doped ceria surfaces, which may help to understand the enhanced catalytic performances of MnO(x)-CeO(2) oxides, as reported in previous experimental works.
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http://dx.doi.org/10.1039/c2cp00061jDOI Listing
April 2012