Publications by authors named "Xueming Liu"

120 Publications

Microwave-enhanced reductive immobilization of high concentrations of chromium in a field soil using iron polysulfide.

J Hazard Mater 2021 Jun 3;418:126293. Epub 2021 Jun 3.

School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Resource Recycling, South China University of Technology, Guangzhou 510006, China; School of Metallurgy and Environment, Central South University, Changsha 410083, China.

High concentrations of Cr(VI) are often detected in contaminated soil. Yet, cost-effective remediation technologies have been lacking. In this study, we prepared a type of FeS based on commercial FeSO.7HO and CaS and tested a microwave-assisted technology based on FeS for reductive immobilization of high concentrations of Cr(VI) in a field contaminated soil. The as-prepared FeS particles appeared as a honeycomb-like and highly porous structure. The microwave-assisted FeS reduction process was able to rapidly reduce the TCLP-based reachability of Cr(VI) from 391.8 to 2.6 mg·L. The dosage of FeS, S/Fe molar ratio, initial moisture content, microwave power, and irradiation time can all affect the treatment effectiveness. After 500 days curing under atmospheric conditions, the TCLP-leached concentration of Cr remained below the regulatory limit of 5 mg·L, while other treatments failed to meet the goal. S or S served as the primary electron donors, whereas Fe facilitated the microwave absorption and the formation of the stable final product of FeCrO. S and Fe are mostly precipitated in soil. The microwave-assisted FeS reduction was shown to be an effective approach to rapidly reduce the leachability of Cr(VI) in contaminated soil, especially in heavily contaminated soil.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126293DOI Listing
June 2021

Nanostructured [email protected] graphene oxide as an efficient hydrogen evolution electrocatalyst in alkaline electrolyte.

J Colloid Interface Sci 2021 May 27;601:570-580. Epub 2021 May 27.

Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures and Jiangsu Provincial Laboratory for Nano Technology, Nanjing University, Nanjing 210093, China.

Metal-organic frameworks (MOFs), serving as precursors or templated to construct nanomaterials, which have gained great attentions in the field of electrocatalysis. However, their applications still remain some challenges due to poor conductivity and easy agglomeration. In this work, the MOFs-derived [email protected] deposited on reduced Graphene Oxide (rGO) surface is designed by using a facile hydrothermal procedure. Attribute to the enlarged active surface area of the nanostructure and the strong synergistic effect between NiCoS and NiCoO, as well as the excellent conductivity of rGO. The [email protected] catalyst displays ultrahigh hydrogen evolution reaction (HER) property and excellent stability, only need an overpotential of η = 95 mV to attain 10 mA cm and deliver a small Tafel slope of b = 52 mV dec in 1 M KOH. This work can provide a window to construct and develop new noble metal-free HER catalysts base on Ni-MOFs served as precursors.
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http://dx.doi.org/10.1016/j.jcis.2021.05.148DOI Listing
May 2021

Giant enhancement of THz-frequency optical nonlinearity by phonon polariton in ionic crystals.

Nat Commun 2021 May 26;12(1):3183. Epub 2021 May 26.

MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin, 300457, China.

The field of nonlinear optics has grown substantially in past decades, leading to tremendous progress in fundamental research and revolutionized applications. Traditionally, the optical nonlinearity for a light wave at frequencies beyond near-infrared is observed with very high peak intensity, as in most materials only the electronic nonlinearity dominates while ionic contribution is negligible. However, it was shown that the ionic contribution to nonlinearity can be much larger than the electronic one in microwave experiments. In the terahertz (THz) regime, phonon polariton may assist to substantially trigger the ionic nonlinearity of the crystals, so as to enhance even more the nonlinear optical susceptibility. Here, we experimentally demonstrate a giant second-order optical nonlinearity at THz frequency, orders of magnitude higher than that in the visible and microwave regimes. Different from previous work, the phonon-light coupling is achieved under a phase-matching setting, and the dynamic process of nonlinear THz generation is directly observed in a thin-film waveguide using a time-resolved imaging technique. Furthermore, a nonlinear modification to the Huang equations is proposed to explain the observed nonlinearity enhancement. This work brings about an effective approach to achieve high nonlinearity in ionic crystals, promising for applications in THz nonlinear technologies.
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http://dx.doi.org/10.1038/s41467-021-23526-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8155090PMC
May 2021

The dose-dependent effects of polyphenols and malondialdehyde on the emulsifying and gel properties of myofibrillar protein-mulberry polyphenol complex.

Food Chem 2021 Oct 5;360:130005. Epub 2021 May 5.

Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou 510610, PR China. Electronic address:

The effects of mulberry polyphenols and malondialdehyde (MDA) on the emulsifying and gel properties of myofibrillar protein (MP) were studied. Emulsibility and gel properties of MP were compared in range of mulberry polyphenol/MDA concentrations by particle size, Zeta potential, antioxidant capacity, gel strength, water-holding capacity (WHC), rheological properties and microstructure. Mulberry polyphenols enhanced the inoxidizability of MP emulsion but decreased its emulsifying property. MDA at intermediate concentrations (5-20 mM) improved the elasticity, strength, and WHC of polyphenols-modified MP emulsion gel, while at high concentration (40 mM) it destroyed the emulsion gel, resulting in "oil leakage". Polyphenol is not conducive to the gelation but weaken the oxidative damage of MDA to protein. The gel structure of MP emulsion collapsed after high dose of polyphenols or MDA treated. Thus, to maintain uniform textural and antioxidant activity of meat product, both polyphenols addition and oxidation intensity should be controlled simultaneously.
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http://dx.doi.org/10.1016/j.foodchem.2021.130005DOI Listing
October 2021

One-step extraction of high-purity CuCl·2HO from copper-containing electroplating sludge based on the directional phase conversion.

J Hazard Mater 2021 07 19;413:125469. Epub 2021 Feb 19.

School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510006, PR China; School of Metallurgy and Environment, Central South University, Changsha, 410083, PR China.

The recovery of heavy metals is a vital way to turn electroplating sludge into resources and reduce its environmental hazards. However, the complex compositions of the polymetallic electroplating sludge severely limit the selective recovery of metal resources such as copper. In this study, we took a kind of copper-containing electroplating sludge (C-ES) as an example present and investigated the process of copper extraction. The copper and other metals were directional converted through an accurate phase transformation process carried out by chlorination combined with thermal regulation. Eventually, the copper was selectively recovered in the form of CuCl·2HO, while the rest of the metals were converted into stable metal salts or oxides. The HCl solution was the best regulator for selective copper recovery. Under the optimal conditions, the recovery of copper approached 97% and the purity of the CuCl·2HO product was about 95%. The kinetic reaction equation of the CuCl volatilization process can be described by Power Low, G(α) = α. The economic estimate based on experimentation indicates the profit of recycling CuCl·2HO is about $23.2/kg. This work provides a novel, simple, and efficient approach to the selective recovery of heavy metal from polymetallic solid wastes.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125469DOI Listing
July 2021

Simultaneous separation and immobilization of Cr(VI) from layered double hydroxide via reconstruction of the key phases.

J Hazard Mater 2021 08 6;416:125807. Epub 2021 Apr 6.

School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou 510006, PR China; School of Metallurgy and Environment, Central South University, Changsha 410083, PR China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, PR China. Electronic address:

Layered double hydroxide (LDH) is one of the key host phases of Cr(VI) in the natural environment and chromite ore processing residue (COPR), causing serious pollution by Cr(VI). Therefore, efficient extraction or immobilization of the incorporated Cr(VI) in LDH is urgently needed. In this work, simultaneous separation and immobilization of Cr(VI) in LDH by using MgCl·6HO under thermal treatment is innovatively proposed. Cr was volatilized as CrCl and was immobilized as MgCrO accounted for 62.2% and 37.8%, respectively, under the optimal condition (the mole ratio of Cl/Cr is 9, 700 °C and 120 min). The underlying reaction mechanisms are as follows: (i) HCl produced by MgCl·6HO accelerates the destruction of Cr(VI)-LDH layer structure, completely exposing the incorporated Cr(VI), (ii) Cr(VI) is reduced to Cr(III) by Cl, part of which is directly immobilized as MgCrO, and the other part generates CrCl, which is volatilized or further combined with Mg to form MgCrO. The total Cr leaching concentration of the practical COPR sample treated by this method dramatically decreases from 421 to 0.7 mg/L, well below the landfill standard limit (4.5 mg/L). This work provides an attainable strategy for thorough remediation of COPR and inspires the treatment of heavy metal-containing LDH.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125807DOI Listing
August 2021

Green spaces mitigate racial disparity of health: A higher ratio of green spaces indicates a lower racial disparity in SARS-CoV-2 infection rates in the USA.

Environ Int 2021 07 27;152:106465. Epub 2021 Feb 27.

Virtual Reality Lab of Urban Environments and Human Health, HKUrbanLabs, The University of Hong Kong, Hong Kong Special Administrative Region; Division of Landscape Architecture, Department of Architecture, The University of Hong Kong, Hong Kong Special Administrative Region. Electronic address:

There is striking racial disparity in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates in the United States. We hypothesize that the disparity is significantly smaller in areas with a higher ratio of green spaces. County level data on the SARS-CoV-2 infection rates of black and white individuals in 135 of the most urbanized counties across the United States were collected. The total population in these counties is 132,350,027, comprising 40.3% of the U.S. population. The ratio of green spaces by land-cover type in each county was extracted from satellite imagery. A hierarchical regression analysis measured cross-sectional associations between racial disparity in infection rates and green spaces, after controlling for socioeconomic, demographic, pre-existing chronic disease, and built-up area factors. We found a higher ratio of green spaces at the county level is significantly associated with a lower racial disparity in infection rates. Four types of green space have significant negative associations with the racial disparity in SARS-CoV-2 infection rates. A theoretical model with five core mechanisms and one circumstantial mechanism is presented to interpret the findings.
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http://dx.doi.org/10.1016/j.envint.2021.106465DOI Listing
July 2021

Green spaces mitigate racial disparity of health: A higher ratio of green spaces indicates a lower racial disparity in SARS-CoV-2 infection rates in the USA.

Environ Int 2021 07 27;152:106465. Epub 2021 Feb 27.

Virtual Reality Lab of Urban Environments and Human Health, HKUrbanLabs, The University of Hong Kong, Hong Kong Special Administrative Region; Division of Landscape Architecture, Department of Architecture, The University of Hong Kong, Hong Kong Special Administrative Region. Electronic address:

There is striking racial disparity in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates in the United States. We hypothesize that the disparity is significantly smaller in areas with a higher ratio of green spaces. County level data on the SARS-CoV-2 infection rates of black and white individuals in 135 of the most urbanized counties across the United States were collected. The total population in these counties is 132,350,027, comprising 40.3% of the U.S. population. The ratio of green spaces by land-cover type in each county was extracted from satellite imagery. A hierarchical regression analysis measured cross-sectional associations between racial disparity in infection rates and green spaces, after controlling for socioeconomic, demographic, pre-existing chronic disease, and built-up area factors. We found a higher ratio of green spaces at the county level is significantly associated with a lower racial disparity in infection rates. Four types of green space have significant negative associations with the racial disparity in SARS-CoV-2 infection rates. A theoretical model with five core mechanisms and one circumstantial mechanism is presented to interpret the findings.
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http://dx.doi.org/10.1016/j.envint.2021.106465DOI Listing
July 2021

Regulation of protein oxidation in Cantonese sausages by rutin, quercetin and caffeic acid.

Meat Sci 2021 May 29;175:108422. Epub 2020 Dec 29.

Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou 510610, PR China. Electronic address:

The effects of rutin, quercetin, and caffeic acid on protein oxidation in Cantonese sausage during 60 days of storage at room temperature (25 ± 1 °C) were investigated. The results showed that the three phenolic compounds played different roles in inhibiting the oxidation of sarcoplasmic and myofibrillar protein. All of them inhibited sarcoplasmic protein oxidation by retarding carbonylation, the conversion of SH to S-S groups, and the formation of dimeric tyrosine and Schiff bases, of which rutin is the most effective. For myofibrillar protein, all of them suppressed the conversion of SH to S-S groups, only caffeic acid inhibited the accumulation of Schiff bases instead of carbonyls while both quercetin and caffeic acid inhibited the formation of dimeric tyrosine. In addition, quercetin had an inverse dosage effect on the oxidation regulation of MP, 0.16 g/kg quercetin had better inhibit effect on protein oxidation than 0.32 g/kg quercetin.
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http://dx.doi.org/10.1016/j.meatsci.2020.108422DOI Listing
May 2021

Robustness and lethality in multilayer biological molecular networks.

Nat Commun 2020 11 27;11(1):6043. Epub 2020 Nov 27.

Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.

Robustness is a prominent feature of most biological systems. Most previous related studies have been focused on homogeneous molecular networks. Here we propose a comprehensive framework for understanding how the interactions between genes, proteins and metabolites contribute to the determinants of robustness in a heterogeneous biological network. We integrate heterogeneous sources of data to construct a multilayer interaction network composed of a gene regulatory layer, a protein-protein interaction layer, and a metabolic layer. We design a simulated perturbation process to characterize the contribution of each gene to the overall system's robustness, and find that influential genes are enriched in essential and cancer genes. We show that the proposed mechanism predicts a higher vulnerability of the metabolic layer to perturbations applied to genes associated with metabolic diseases. Furthermore, we find that the real network is comparably or more robust than expected in multiple random realizations. Finally, we analytically derive the expected robustness of multilayer biological networks starting from the degree distributions within and between layers. These results provide insights into the non-trivial dynamics occurring in the cell after a genetic perturbation is applied, confirming the importance of including the coupling between different layers of interaction in models of complex biological systems.
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http://dx.doi.org/10.1038/s41467-020-19841-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7699651PMC
November 2020

Roles of MOV10 in Animal RNA Virus Infection.

Front Vet Sci 2020 16;7:569737. Epub 2020 Sep 16.

Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an, China.

Animal epidemic diseases caused by RNA viruses are the primary threat to the livestock industry, and understanding the mechanisms of RNA virus clearance from target cells is critical to establish an effective method to reduce economic losses. As an SF-1, ATP-dependent RNA helicase in the UPF1p family, MOV10 participates in the RNA degradation of multiple viruses mediated via miRNA pathways and therefore contributes to a decrease in the replication of RNA viruses. This review primarily focuses on the bioactivity of MOV10, the mechanism of RNA virus removal, and the potential roles of MOV10 in RNA virus clearance. In addition, clues are provided to reduce animal diseases caused by RNA viruses.
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http://dx.doi.org/10.3389/fvets.2020.569737DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7524886PMC
September 2020

Full-field real-time characterization of creeping solitons dynamics in a mode-locked fiber laser.

Opt Lett 2020 Nov;45(22):6246-6249

Creeping solitons, which belong to the class of pulsating solitons, can be meaningful for fundamental physics owing to their fruitful nonlinear dynamics. Their characteristics in mode-locked lasers have been studied theoretically, but it is difficult to experimentally observe evolution dynamics in real time. Here, we have experimentally observed the temporal and spectral evolution dynamics of creeping solitons in a passively mode-locked fiber laser by employing time-lens and dispersive Fourier transform technique. With the aid of Raman amplification, the measured recording length of the time lens in the asynchronous mode could be substantially improved. Temporal soliton snaking motion and spectral breathing dynamics are experimentally obtained, confirming intrinsic feature of pulsation dynamics. These results display how single-shot measurements can offer new insights into ultrafast transient dynamics in nonlinear optics.
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http://dx.doi.org/10.1364/OL.404778DOI Listing
November 2020

FeP-decorated N,P Codoped Carbon Synthesized via Direct Biological Recycling for Endurable Sulfur Encapsulation.

ACS Cent Sci 2020 Oct 25;6(10):1827-1834. Epub 2020 Sep 25.

Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.

In spite of the great potential in leading next-generation energy storage technology, Li-S batteries suffer rapid capacity decay arising from the shuttling effect of lithium polysulfides (LiPSs), a major concern that must be addressed before commercialization can be realized. To tackle this challenge, we demonstrate a facile approach to fabricate a hierarchically structured composite of [email protected], phosphorus codoped carbon ([email protected]) by direct biological recycling of iron metal from electroplating sludge using bacteria. This material, featuring uniform dispersion of FeP nanoparticles (NPs) in porous NPC matrix, effectively adapts volume variation of sulfur upon cycling and simultaneously provides multiple channels for efficient lithium ion transport. In addition, FeP NPs with strong adhesion properties of tightly anchored soluble LiPSs formed during discharge can significantly facilitate the decomposition of LiS during the subsequent charging process. The Li-S cell built on this cathode architecture delivers high specific capacity (1555.7 mAh g at 0.1 C), appreciable rate capability (679.7 mAh g at 10 C), and greatly enhanced cycling performance (761.9 mAh g at 1.0 C after 500 cycles).
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http://dx.doi.org/10.1021/acscentsci.0c00899DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7596857PMC
October 2020

Unveiling external motion dynamics of solitons in passively mode-locked fiber lasers.

Opt Lett 2020 Sep;45(17):4835-4838

Real-time measurement of ultrafast pulses together with high temporal resolution and long recording length is an urgent requirement of all optical communication systems and nonlinear science. Here, external motion dynamics of soliton pairs in mode-locking ultrafast fiber lasers can be single-shot characterized with long recording length, by using an asynchronous four-wave-mixing (FWM)-based temporal magnifier (AFTM) system. Recording length of more than one thousand roundtrips can be achieved through the AFTM system. Temporal propagation dynamics of soliton pairs with tunable separations are observed, revealing that soliton pairs with narrower separation display vibration-like dynamics, while the two solitons with wider separation remain relatively unchanged. We believe our results will provide a promising solution for real-time measurement of ultrafast pulse and can offer novel insights for ultrafast transient dynamics in nonlinear optics.
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http://dx.doi.org/10.1364/OL.394544DOI Listing
September 2020

Microfiber-assisted gigahertz harmonic mode-locking in ultrafast fiber laser.

Opt Lett 2020 Sep;45(17):4678-4681

Optoacoustic interaction can be strongly enhanced in tiny core fibers, and it holds significant potential for stable harmonic mode-locking at gigahertz (GHz) and higher repetition rate. In this Letter, we propose and demonstrate a microfiber-assisted GHz harmonic mode-locking fiber laser, which is achieved by the enhanced optomechanical coupling between cavity modes in microfiber with the waist length of ∼16 and the waist diameter of ∼1.56µ. The repetition rates can be stably locked at 2.3828 GHz and predominately locked at 1.7852 GHz, corresponding to the frequencies of radial and torsional-radial acoustic modes, respectively. Our results provide novel insight into the design of a high-repetition-rate laser source and the application of microfibers in the optomechanical field.
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http://dx.doi.org/10.1364/OL.399915DOI Listing
September 2020

Convenient fabrication of a core-shell [email protected] anode for lithium storage from tinplate electroplating sludge.

Chem Commun (Camb) 2020 Sep;56(70):10187-10190

Guangzhou Key Laboratory of Surface Chemistry of Energy Materials, New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, P. R. China.

We here report a unique preparation of a high-performance core-shell [email protected] anode for lithium ion batteries (LIBs) from tinplate electroplating sludge via a convenient process without deep purification. The [email protected] shows excellent electrochemical performance due to its core-shell structure. This work provides insight into addressing the electroplating sludge and designing high-performance LIB anodes.
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http://dx.doi.org/10.1039/d0cc04403bDOI Listing
September 2020

Co-adaptation enhances the resilience of mutualistic networks.

J R Soc Interface 2020 07 22;17(168):20200236. Epub 2020 Jul 22.

Department of Computer Science and Network Science and Technology Center, Troy, NY 12180, USA.

Mutualistic networks, which describe the ecological interactions between multiple types of species such as plants and pollinators, play a paramount role in the generation of Earth's biodiversity. The resilience of a mutualistic network denotes its ability to retain basic functionality when errors and failures threaten the persistence of the community. Under the disturbances of mass extinctions and human-induced disasters, it is crucial to understand how mutualistic networks respond to changes, which enables the system to increase resilience and tolerate further damages. Despite recent advances in the modelling of the structure-based adaptation, we lack mathematical and computational models to describe and capture the co-adaptation between the structure and dynamics of mutualistic networks. In this paper, we incorporate dynamic features into the adaptation of structure and propose a co-adaptation model that drastically enhances the resilience of non-adaptive and structure-based adaptation models. Surprisingly, the reason for the enhancement is that the co-adaptation mechanism simultaneously increases the heterogeneity of the mutualistic network significantly without changing its connectance. Owing to the broad applications of mutualistic networks, our findings offer new ways to design mechanisms that enhance the resilience of many other systems, such as smart infrastructures and social-economical systems.
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http://dx.doi.org/10.1098/rsif.2020.0236DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7423412PMC
July 2020

Identification of the key host phases of Cr in fresh chromite ore processing residue (COPR).

Sci Total Environ 2020 Feb 1;703:135075. Epub 2019 Nov 1.

School of Environment and Energy, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), South China University of Technology, Guangzhou 510006, PR China; Guangdong Engineering and Technology Research Center for Environmental Nanomaterials, South China University of Technology, Guangzhou 510006, PR China.

Chromite ore processing residue (COPR) poses a serious Cr(VI) pollution to the environment, and ascertaining the Cr speciation in COPR is significant for guiding remediation. In this study, a systematic investigation on the Cr speciation in fresh COPR was carried out by multiple quantification methods as follows: i) via X-ray absorption spectroscopy (XAS), it was determined that 35% of the total Cr is Cr(VI); ii) the host phases of Cr(VI) and Cr(III) were identified and their Cr content were analyzed by X-ray diffraction (XRD), scanning electron microscopy combined with energy dispersive spectroscopy (SEM-EDS) and leaching tests; iii) the weight percent of each Cr host phase was determined by EDS-assisted quantitative phase analysis; iv) the Cr occupancy percentage of each Cr host phase was determined by integrative calculation based on the above analysis. Results indicate that brownmillerite, hydrogarnet and amorphous phase are the key host phases of Cr(VI), which hold 24.2%, 19.6% and nearly 50% of the total Cr(VI), respectively; spinel and amorphous phase are the key host phases of Cr(III), which hold 25.4% and 71.9% of the total Cr(III), respectively. This study has improved the understanding of Cr speciation in COPR, which is significant for developing effective and practical remediation technology. The quantification methods employed in this study can be extended to research on the speciation of Cr or other metals in other solid wastes.
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http://dx.doi.org/10.1016/j.scitotenv.2019.135075DOI Listing
February 2020

Effects of mulberry polyphenols on oxidation stability of sarcoplasmic and myofibrillar proteins in dried minced pork slices during processing and storage.

Meat Sci 2020 Feb 18;160:107973. Epub 2019 Oct 18.

Guangdong Engineering Center for Biopharmaceuticals, School of Biology and Biological Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Panyu, Guangzhou 510006, China; College of Life and Geographic Sciences, Kashi University, Kashi 844000, China; The Key Laboratory of Ecology and Biological Resources in Yarkand Oasis at College & University under the Department of Education of Xinjiang Uygur Autonomous Region, Kashi University, Kashi 844000, China. Electronic address:

This experiment was designed to evaluate the influence of mulberry polyphenols (MP) on oxidation stability of sarcoplasmic and myofibrillar proteins in dried minced pork slice during processing and storage. Composition, amino acid side chain modification, average particle size, hydrophobicity and solubility of proteins in the slices were investigated. MP displayed protective effects on oxidation stability of sarcoplasmic and myofibrillar proteins in slices, considering carbonyl formation and transformation from SH group to SS group were remarkably retarded by MP. Proteins in MP-treated slices possessed larger average particle size but lower aggregation during processing and storage. Meanwhile, the strengthened ionic bonds and weakened hydrogen, hydrophobic and disulfide bond could be responsible for the improved protein stability of slice with MP. All these results suggested that mulberry polyphenol could improve protein oxidation stability in meat products.
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http://dx.doi.org/10.1016/j.meatsci.2019.107973DOI Listing
February 2020

Insight into the conformational and functional properties of myofibrillar protein modified by mulberry polyphenols.

Food Chem 2020 Mar 16;308:125592. Epub 2019 Oct 16.

Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs, Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou 510610, PR China. Electronic address:

This paper investigated the conformational and functional properties of myofibrillar protein modified by five phenolic compounds, including cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, caffeic acid, quercetin and rutin, dominantly presented in mulberry polyphenols-enriched sausage. These phenolic compounds significantly affected the structure of myofibrillar protein as indicated by the remarkable losses of carbonyl and ε-NH and the obviously fluorescence quenching effect (P < 0.05). Modified myofibrillar protein increased antioxidative activity but decreased thermal stability. Myofibirllar protein modified with rutin had no change in thermal stability but improved emulsifying properties. Quercetin has little effect on secondary structure of myofibirlliar protein. Caffeic acid triggered the conversion of α-helix to β-sheet in myofibrillar protein, and the resulted protein exhibited the strongest fluorescence quenching, solubility and antioxidant activity among all samples. Overall, the results suggested that all phenolic compounds involved in the changes of meat product quality, with caffeic acid and rutin being the most critical ones.
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http://dx.doi.org/10.1016/j.foodchem.2019.125592DOI Listing
March 2020

Revealing the Transition Dynamics from Q Switching to Mode Locking in a Soliton Laser.

Phys Rev Lett 2019 Aug;123(9):093901

Optical Sciences Group, Research School of Physics and Engineering, The Australian National University, Canberra 2600, Australian Capital Territory, Australia.

Q switching (QS) and mode locking (ML) are the two main techniques enabling generation of ultrashort pulses. Here, we report the first observation of pulse evolution and dynamics in the QS-ML transition stage, where the ML soliton formation evolves from the QS pulses instead of relaxation oscillations (or quasi-continuous-wave oscillations) reported in previous studies. We discover a new way of soliton buildup in an ultrafast laser, passing through four stages: initial spontaneous noise, QS, beating dynamics, and ML. We reveal that multiple subnanosecond pulses coexist within the laser cavity during the QS, with one dominant pulse transforming into a soliton when reaching the ML stage. We propose a theoretical model to simulate the spectrotemporal beating dynamics (a critical process of QS-ML transition) and the Kelly sidebands of the as-formed solitons. Numerical results show that beating dynamics is induced by the interference between a dominant pulse and multiple subordinate pulses with varying temporal delays, in agreement with experimental observations. Our results allow a better understanding of soliton formation in ultrafast lasers, which have widespread applications in science and technology.
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http://dx.doi.org/10.1103/PhysRevLett.123.093901DOI Listing
August 2019

Facile Preparation of Super Absorbent from Calcium-Aluminum Waste Residue and Its Application for Adsorption of Congo Red.

J Nanosci Nanotechnol 2020 02;20(2):769-778

Ministry Key Laboratory of Oil and Gas Fine Chemicals, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, China.

A super absorbent was synthesized from calcium-aluminum waste residue of aluminum industrial using a facile hydrothermal method. The XRD results revealed that the main phase of hydrothermal product at 120 °C is CaSO₄ ·2H₂O, with a small amount of Al(OH)₃. The as-prepared products were used to investigate the adsorptive applications in Congo red (CR) removal, and the results showed that the products treated at 120 °C had the best adsorption properties. The maximum adsorption capacity reaches about 1860.11 mg/g with a removal rate of 99.75%. Furthermore, the used adsorbent could be regenerated for at least four cycles through a calcination procedure, indicating its potential as an excellent adsorbent for the removal of CR dye from wastewater. The adsorption behavior was analyzed by Langmuir, Freundlich and Sips isotherms, and the adsorption proved to be a multilayer adsorption. This facile method presented here may provide promise synthesis of high-effective and low-cost adsorbents from industrial solid waste and achieve the goal of "using waste to treat waste" in the future.
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http://dx.doi.org/10.1166/jnn.2020.16935DOI Listing
February 2020

Crystal regulation of gypsum via hydrothermal treatment with hydrogen ion for Cr(VI) extraction.

J Hazard Mater 2020 05 6;390:120614. Epub 2019 May 6.

School of Environment and Energy, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), South China University of Technology, Guangzhou, 510006, PR China; Guangdong Engineering and Technology Research Center for Environmental Nanomaterials, Guangzhou, 510006, PR China.

Heavy metal-containing gypsum is a widespread hazardous waste. In this work, H was found to be the most essential factor of the mineralizers in hydrothermal treatment to completely (≥99.8%) extract Cr(VI) from gypsum waste to the supernatant, where the significant growth (from several μm to several hundreds of μm) and perfection of the gypsum crystals were observed. Moreover, with increasing concentration of H, the crystal growth (undergoing Ostwald ripening process) was accelerated and the phase transformation temperature of gypsum was decreased from 110℃ (at 0.2 mol/L of HCl) to 100℃ (at 0.3 mol/L of HCl), which are favorable to enhance Cr(VI) extraction efficiency. Pilot experiments further certified this method to be practicable even in ton-scale. This work proposes a practicable and universal method to completely extract Cr(VI) from gypsum waste, and would also inspire the recycle of gypsum waste containing other heavy metals, such as As, Pb, Cd, and Hg.
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http://dx.doi.org/10.1016/j.jhazmat.2019.05.007DOI Listing
May 2020

Potentially toxic elements in solid waste streams: Fate and management approaches.

Environ Pollut 2019 Oct 9;253:680-707. Epub 2019 Jul 9.

Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. Electronic address:

Solid wastes containing potentially toxic elements (PTEs) are widely generated around the globe. Critical concerns have been raised over their impacts on human health and the environment, especially for the exposure to PTEs during the transfer and disposal of the wastes. It is important to devise highly-efficient and cost-effective treatment technologies for the removal or immobilisation of PTEs in solid wastes. However, there is an inadequate overview of the global flow of PTEs-contaminated solid wastes in terms of geographical distribution patterns, which is vital information for decision making in sustainable waste management. Moreover, in view of the scarcity of resources and the call for a circular economy, there is a pressing need to recover materials (e.g., precious metals and rare earth elements) from waste streams and this is a more sustainable and environmentally friendly practice compared with ore mining. Therefore, this article aims to give a thorough overview to the global flow of PTEs and the recovery of waste materials. This review first summarises PTEs content in various types of solid wastes; then, toxic metal(loid)s, radioactive elements, and rare earth elements are critically reviewed, with respect to their patterns of transport transformation and risks in the changing environment. Different treatments for the management of these contaminated solid wastes are discussed. Based on an improved understanding of the dynamics of metal(loid) fates and a review of existing management options, new scientific insights are provided for future research in the development of high-performance and sustainable treatment technologies for PTEs in solid wastes.
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http://dx.doi.org/10.1016/j.envpol.2019.07.012DOI Listing
October 2019

Effect of Flammulina velutipes on the physicochemical and sensory characteristics of Cantonese sausages.

Meat Sci 2019 Aug 3;154:22-28. Epub 2019 Apr 3.

Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510610, PR China; Key Laboratory of Functional Foods, Ministry of Agriculture, Guangzhou 510610, PR China; Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou 510610, PR China.

The effects of fresh and dried Flammulina velutipes (FFV and DFV) on quality and sensory characteristics of Cantonese sausages were investigated. Sausage samples were prepared by adding 0% (control), 2.5% FFV, 2.5% and 5.0% DFV, respectively, and their nutritional compositions, free amino acid profiles, lipid and protein oxidation, color and texture properties were determined. Addition of F. velutipes significantly decreased fat content while increased free amino acid contents of Cantonese sausages. Total free amino acid contents of 2.5% FFV, 2.5% DFV and 5.0% DFV incorporation were 2.8-, 2.4- and 3.5-fold as compared to control, respectively. Lipid and protein oxidation of Cantonese sausages were effectively inhibited by the addition of F. velutipes. Both FFV and DFV addition decreased hardness and chewiness while showed different effect on yellowness of samples. DFV added at 2.5% exhibited the best overall sensory acceptance. Therefore, appropriate addition of F. velutipes may be an effective way to improve meat product quality and function.
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http://dx.doi.org/10.1016/j.meatsci.2019.04.003DOI Listing
August 2019

Multiple phase transitions in networks of directed networks.

Phys Rev E 2019 Jan;99(1-1):012312

Department of Computer Science, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.

The robustness in real-world complex systems with dependency connectivities differs from that in isolated networks. Although most complex network research has focused on interdependent undirected systems, many real-world networks-such as gene regulatory networks and traffic networks-are directed. We thus develop an analytical framework for examining the robustness of networks made up of directed networks of differing topologies. We use it to predict the phase transitions that occur during node failures and to generate the phase diagrams of a number of different systems, including treelike and random regular (RR) networks of directed Erdős-Rényi (ER) networks and scale-free networks. We find that the the phase transition and phase diagram of networks of directed networks differ from those of networks of undirected networks. For example, the RR networks of directed ER networks show a hybrid phase transition that does not occur in networks of undirected ER networks. In addition, system robustness is affected by network topology in networks of directed networks. As coupling strength q increases, treelike networks of directed ER networks change from a second-order phase transition to a first-order phase transition, and RR networks of directed ER networks change from a second-order phase transition to a hybrid phase transition, then to a first-order phase transition, and finally to a region of collapse. We also find that heterogenous network systems are more robust than homogeneous network systems. We note that there are multiple phase transitions and triple points in the phase diagram of RR networks of directed networks and this helps us understand how to increase network robustness when designing interdependent infrastructure systems.
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http://dx.doi.org/10.1103/PhysRevE.99.012312DOI Listing
January 2019

Upcycling of Electroplating Sludge into Ultrafine [email protected] Nanorods with Highly Stable Lithium Storage Performance.

Nano Lett 2019 03 14;19(3):1860-1866. Epub 2019 Feb 14.

School of Environment and Energy, The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education) , South China University of Technology , Guangzhou , Guangdong 510006 , China.

Sn-based anode materials have become potential substitutes for commercial graphite anode due to their high specific capacity and good safety. In this paper, ultrafine Sn nanoparticles embedded in nitrogen and phosphorus codoped porous carbon nanorods ([email protected]) are obtained by carbonizing bacteria that adsorb the Sn electroplating sludge extracting solution. The as-prepared [email protected] rod-shaped composite exhibits superior electrochemical Li-storage performances, such as a reversible capacity of approximate 560 mAh/g at 1 A/g and an ultralong cycle life exceeding 1500 cycles, with approximately no capacity decay. The ultrastable structure of the [email protected] was revealed using in situ transmission electron microscope at the nanoscale and indicated that the [email protected] composite could restrict the volume expansion of Sn nanoparticles during the lithiation/delithiation cycles. This work provides a new insight into addressing the electroplating sludge and designing novel lithium ion battery anodes.
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http://dx.doi.org/10.1021/acs.nanolett.8b04944DOI Listing
March 2019

Off-site and on-site vortex solitons in space-fractional photonic lattices.

Opt Lett 2018 Dec;43(23):5749-5752

We address the existence and stability of off-site and on-site vortex solitons with a unit topological charge in space-fractional Kerr lattices. In contrast to the reported ordinary Kerr lattices, vortex solitons in the proposed space-fractional lattices are stable only in the intermediate region of propagation constant, and this region widens rapidly with the increase of a Lévy index. Under the same Lévy index, the stability range of on-site vortices is larger than that of off-site ones. In particular, for on-site vortex solitons, the upper edge of the stability range appears where the maximum of soliton power is located, which provides an effective way to identify the stability range of on-site vortices. Our results extend the study of vortex solitons into space-fractional systems and deepen the understanding of Kerr lattices in fractional dimensions.
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http://dx.doi.org/10.1364/OL.43.005749DOI Listing
December 2018

Effective Extraction of Cr(VI) from Hazardous Gypsum Sludge via Controlling the Phase Transformation and Chromium Species.

Environ Sci Technol 2018 11 24;52(22):13336-13342. Epub 2018 Oct 24.

School of Environment and Energy , South China University of Technology , Guangzhou , 510006 , China.

Through controlling the phase transformation and chromium species under hydrothermal condition, the Cr(VI) was extracted fully from hazardous Cr(VI)-containing gypsum sludge, with a very high efficiency of more than 99.5%. Scanning transmission electron microscopy, X-ray absorption fine structure, and density functional theory calculation results revealed that the dissolution-recrystallization of CaSO·2HO into CaSO was the key factor to fully release the encapsulated Cr(VI). Moreover, the mineralizer (persulfate salt) provided H and SO ions, the former made an acidic condition to transform the released CrO into the specie (CrO) with less similarity to SO, which further prevented the recombination of the released Cr(VI) with gypsum; and the latter was essential to accelerate crystal growth of calcium sulfate so as to enhance Cr(VI) extraction. This work would provide an instructive guidance to fully extract heavy metals from hazardous solid wastes via the control of crystal transformation and the pollutant species.
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http://dx.doi.org/10.1021/acs.est.8b02213DOI Listing
November 2018

Real-Time Observation of the Buildup of Soliton Molecules.

Phys Rev Lett 2018 Jul;121(2):023905

State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.

Real-time spectroscopy access to ultrafast fiber lasers opens new opportunities for exploring complex soliton interaction dynamics. Here, we have reported the first observation, to the best of our knowledge, of the entire buildup process of soliton molecules (SMs) in a mode-locked laser. We have observed that the birth dynamics of a stable SM experiences five different stages, i.e., the raised relaxation oscillation (RO) stage, beating dynamics stage, transient single pulse stage, transient bound state, and finally the stable bound state. We have discovered that the evolution of pulses in the raised RO stage follows a law that only the strongest one can ultimately survive and, meanwhile, the pulses periodically appear at the same temporal positions for all lasing spikes during the same RO stage (named as memory ability) but they lose such ability between different RO stages. Moreover, we have found that the buildup dynamics of SMs is quite sensitive to both the polarization state of intracavity light and the fluctuation of pump power. These results provide new perspectives into the ultrafast transient process in mode-locked lasers and the dynamics of complex nonlinear systems.
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http://dx.doi.org/10.1103/PhysRevLett.121.023905DOI Listing
July 2018
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