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1

Transcriptome response to phosphorus starvation in rice

100%

Cai H. , Xie W. , Zhu T. , Lian X.

Acta Physiologiae Plantarum

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2012

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tom 34

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nr 1

EN

Phosphorus (P) is an essential mineral nutrient required for the plant growth and development. Insufficient P supply triggers extensive physiological and biochemical changes in plants. In this study, we used Affymetrix GeneChip rice genome arrays to analyze the dynamics of rice transcriptome under P starvation. Phosphorus starvation induced or suppressed transcription of 2,317 genes, representing 7.2% of the genes. These changes, mostly transient, affected various cellular metabolic pathways including stress response, primary and secondary metabolism, molecular transport, regulatory process and organismal development. Hundred and thirty (5.6% of 2,317 genes) transcripts were expressed similarly both in root and shoot under P starvation. Comparative analysis between rice and Arabidopsis identified 37 orthologous groups that responded to P starvation demonstrating the existence of conserved P stress coupling mechanism among dicot and monocot plants. Additional analysis of transcription profiles of microRNAs revealed differential expression of miR399 and miR169 under P starvation suggesting their potential roles in plant nutrient homeostasis. Analysis of genome-wide gene expression profiles in P starvation in rice shoot and root, using Affymetrix Rice Genome Chip in this paper, has provided an overview of transcriptional responses to the P starvation condition. This will bring very valuable information and will make a great contribution for investigating the response of rice to P starvation.

2

Investigation on self‑healing of neat and polymer modified asphalt binders

100%

Wang C. , Xue L. , Xie W. , Cao W.

Archives of Civil and Mechanical Engineering

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2020

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tom Vol. 20, no. 2

27--36

EN

The paving asphalts have long been recognized to be capable of self-healing. The objective of this study was to evaluate the healing potential of asphalt binders and investigate its relationship with molecular characteristics in terms of composition and structures. Five neat and styrene–butadiene–styrene (SBS) modified asphalt binders were characterized using the recently developed linear amplitude sweep-based healing test. The data were analyzed based on the viscoelastic continuum damage theory to establish healing master curves and determine the healing rate HR. Chemical evaluation methods included saturates, aromatics, resins, and asphaltenes fractionation, gel permeation chromatography, and nuclear magnetic resonance spectroscopy. Results indicated that the presence of more light/low-polarity fractions of saturates and aromatics or higher concentrations of small molecules promoted healing, as these molecules were expected to have higher mobility facilitating molecular diffusion across crack interfaces. Lower percentages of aromatic ring structures and more aliphatic chains corresponded to higher healing rates. The SBS-modified asphalt binders contained higher concentrations of aromatic rings, but still provided comparable healing potential with the neat asphalts.

3

Biology and chemistry of fumonisin and AAL toxins

100%

Mirocha C. J. , Chen J. , Xie W. , Xu Y.

Hodowla Roślin, Aklimatyzacja i Nasiennictwo

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1993

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tom 37

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nr 1-2

4

Research on quantifying the hydrophilicity of leached coals by FTIR spectroscopy

88%

Wang J. , He Y. , Yang Y. , Xie W. , Ling X.

Physicochemical Problems of Mineral Processing

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2017

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tom Vol. 53, iss. 1

227--239

EN

Surface properties play important roles in characterization of structural parameters and the hydrophilicity index. Accurate analysis of the macerals rather than the average properties of the macerals and minerals are crucial for these parameters and indexes. In order to improve the accuracy of analyzing coal surface property, HF/HCl acid leaching was applied to eliminate the interference of minerals. FTIR was used to characterize the differences in surface chemical composition between raw and processed coal. Moreover, each functional group was analyzed quantitatively. Based on these quantitative data, the structural parameters and hydrophilicity indexes were calculated. From the results of FTIR, the peaks of mineral cover up the types of the organic peaks, such as -COOH and aromatic CH stretching. In addition, they decrease the intensity of the peak such as C=C and aromatics CHx out-of-plane deformation in the spectra of raw coals. However, it provided the accurate types and contents of organic functional groups of the macerals after acid leaching. The structural parameter results indicate that the values cannot reflect the coal ranks through the surface properties of raw coals while they show a good relationship with the degree of coalification in the analysis of processed coals. Besides, the hydrophilicity indexes are verified by the natural floatability of coal macerals of the processed coals. It is also found that the processed lignite coal cannot be floated despite elimination of the hydrophilic minerals. The main reason of hard-to-float property of lignite coal lies in a strong hydrophilicity of macerals.

5

Adsorption behavior of surfactants on lignite particles with different densities in aqueous medium

75%

Wang J. , He Y. , Wen B. , Ling X. , Xie W. , Wang S.

Physicochemical Problems of Mineral Processing

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2017

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tom Vol. 53, iss. 2

996--1008

EN

Lignite is well known for its strong hydrophilicity and hard-to-float properties. However, the surface free energy of the solid is made up of two components, that is the Lifshitz-van der Waals and acid-base interaction energy. Differences in these two components between the low ash (lower density) and high ash fraction (higher density) provide a benefit for improving the separation efficiency through introducing surfactants in flotation. In this paper, thermodynamic characterization of three density lignite fractions was measured by a Washburn dynamic method. Combining the Washburn equation and Van Oss-Chaudhury-Good theory, the surface free energy components of three samples were calculated according to the wetting process by n-hexane, diiodomethane, deionized water and ethylene glycol. The Lifshitz-van der Waals part of surface free energy reduced with the coal density increase, especially between fractions of -1.45 g/cm3 and 1.45-1.80 g/cm3, while the Lewis base part increased slightly. The interfacial interaction free energies between the surfactant and lignite in aqueous medium indicated that the low hydrophilic index benefited for the stronger adsorption intensity. Increase of the surfactant Lifshitz-van der Waals component increases the adsorptive intensity on lower density lignite and the repulsive intensity on higher density lignite, which is beneficial for separation.

6

Response of energy-size reduction to the control of circulating load in vertical spindle pulverizer

75%

Li H. , He Y. , Zhang Y. , Ge Z. , Xie W. , Wang S. , Li K.

Physicochemical Problems of Mineral Processing

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2017

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tom Vol. 53, iss. 2

793--801

EN

In the vertical spindle pulverizer (VSP), the large circulation ratio and high ash and sulfur contents in circulating load would result in intensive energy consumption and low grinding efficiency. Although the control of circulating load would help increase the energy efficiency, no quantitative study has been conducted due to the high temperature and pressure in the closed VSP. In this study, response of energy-size reduction to the control of circulating load was studied by the experimental simulation method. Coal mixtures with fine/coarse ratio of 11:1, 8:1 and 6:1 were ground by a lab-scale roller mill. Energy-size reductions of the coarse coal were compared to evaluate the influence of circulating load control. Results showed that the product with the coarse coal increased by 30% when the specific breakage energy was 1.0 kWht–1 as the circulation ratio decreased from 11 to 6. Meanwhile, a breakage characteristic index of the coarse coal was two times higher due to the cushioning effect of fines. Besides, decrease of circulation ratio led to increase of the breakage rate of coarse coal, and the energy saving improved by 57%. With the same energy input of 2.0 kWht-1, the yield of –0.09 mm pulverized fuel (PF) increased from 22 to 43%. Therefore, controlling the circulating load is an effective method to improve the breakage rate of coarse coal and energy efficiency for PF generation.

7

Concentrations of heavy metals in six municipal sludges from Guangzhou and their potential ecological risk assessment for agricultural land use

63%

Liu J. , Zhou Z. , Sun S. , Ning X. , Zhao S. , Xie W. , Wang Y. , Zheng L. , Huang R. , Li B.

Polish Journal of Environmental Studies

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2015

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tom 24

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nr 1

EN

Six kinds of municipal sludge samples were collected from wastewater treatment plants (WWTPs) from Guangzhou in southern China. Total concentration of Cu, Pb, Zn, Cr, Ni, Cd, and Mn in the sludge was determined, and used obtained values to appraise the degree of agricultural land pollution on the base of four pollution indixes. Results showed that the concentrations of the heavy metals Cu (4.567 mg/kg), Mn (1.844 mg/kg), Ni (148 mg/kg), Cr (121 mg/kg), and Cd (5.99 mg/kg) in S1 sludge were higher than that of the other sludges. In six sludge samples the concentrations of Mn, Zn, and Cu were highest, followed by Ni, Pb, and Cr. Cd had the lowest concentration. All were higher than those recorded in the background data for crop soils. With the exception of Cu and Cd from site S1, and Ni from sites S1, S2, and S5, all other metal concentrations conformed to permissible levels prescribed by the national application standard of acid soil in China (GB18918-2002). The geoaccumulation index (Igeo) assessment results indicate that there are serious risks in agricultural utilization for the existing Cu and Zn in these six kinds of sludges, especially the Igeo, which was 6.53 for Cu, 3.21 for Mn, 2.78 for Cd in the S1 sludge. The results of RI showed that sludge had high potential ecological risks, especially caused by Cd, which should give rise to widespread concerns. The potential ecological risk index (RI) of heavy metals in six sludge samples was ranked in the order of S1>S2>S4>S3>S5>S6.

8

Comparison of float-sink and progressive release flotation of ground products of coal middlings

63%

Xie W. , He Y. , Luo C. , Zhang X. , Li H. , Yu J. , Wang H. , Shi F.

Physicochemical Problems of Mineral Processing

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2015

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tom Vol. 51, iss. 2

675--684

EN

An additional recovery of coking coal middlings can be utilized for increasing of the concentrate yield of coking coal. A combined flow sheet of comminution and flotation can realize this target. To investigate the effect of grinding process on further flotation of ground products, progressive release flotation tests were used to compare with the float-sink tests, which were regarded as a criterion. Coal middlings were ground by wet-milling with iron balls to <0.5 mm. Curves of ash vs. cumulative yields of sized products indicated that the concentrate yield of coal separated by progressive release flotation was lower than that of coal benefited by the float-sink test, with the same ash for four size fractions (0.5-0.25 mm, 0.25-0.125 mm, 0.125-0.074 mm and <0.074 mm). Distributions of elements conducted by energy disperse spectroscopy (EDX) showed that associated kaolinite was liberated and exposed on the surface. It led to the shift of local surface property from hydrophobicity to hydrophilicity. Meanwhile, analyses of chemical property performed by an X-Ray photoelectron spectrometer (XPS) depicted that the hydrophilic mineral FeOOH, which generated in the grinding process, was adsorbed on the coal surface. Flotation of the ground products were worsened due to the increase of hydrophilicity of the coal surface.