Publications by authors named "Lingwei Li"

15 Publications

  • Page 1 of 1

Switchable Binding Energy of Ionic Compounds and Application in Customizable Ligand Exchange for Colloid Nanocrystals.

J Phys Chem Lett 2021 Jun 1;12(22):5271-5278. Epub 2021 Jun 1.

Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic Science and Engineering, Faculty of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an, Shannxi 710049, P. R. China.

The ability to engineer the surface ligands or adsorbed molecules on colloid nanocrystals (NCs) is important for various applications, as the physical and chemical properties are strongly affected by the surface chemistry. Here, we develop a facile and generalized ionic compound-mediated ligand-exchange strategy based on density functional theory calculations, in which the ionic compounds possess switchable bonding energy when they transfer between the ionized state and the non-ionized state, hence catalyzing the ligand-exchange process. By using an organic acid as the intermediate ligand, ligands such as oleylamine, butylamine, polyvinylpyrrolidone, and poly(vinyl alcohol) can be freely exchanged on the surface of Au NCs. Benefiting from this unique ligand-exchange strategy, the ligands with strong bonding energy can be replaced by weak ones, which is hard to realize in traditional ligand-exchange processes. The ionic compound-mediated ligand exchange is further utilized to improve the catalytic properties of Au NCs, facilitate the loading of nanoparticles on substrates, and tailor the growth of colloid NCs. These results indicate that the mechanism of switchable bonding energy can be significantly expanded to manipulate the surface property and functionalization of NCs that have applications in a wide range of chemical and biomedical fields.
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http://dx.doi.org/10.1021/acs.jpclett.1c00669DOI Listing
June 2021

Solution-Based SERS Detection of Weak Surficial Affinity Molecules Using Cysteamine-Modified Au Bipyramids.

Anal Chem 2021 06 20;93(21):7657-7664. Epub 2021 May 20.

School of Electronics and Information Engineering, Xi'an Jiaotong University, Xi'an, Shannxi 710049, China.

To achieve ultrasensitive detection of trace targets through solution-based surface-enhanced Raman spectroscopy (SERS), direct adsorption of the target molecules on a SERS-active surface is vital. In this work, cetyltrimethylammonium bromide (CTAB)-capped gold nano-bipyramids (Au BPs) with different aspect ratios (ARs) are prepared and the surface is successfully modified by a simple ligand exchange method. Cysteamine-capped gold nano-bipyramids (cyst-Au BPs) are obtained by means of replacement of CTAB by cysteamine using Au-S covalent bonding and applied in the solution-based SERS detection of different pigment molecules, which always have weak affinity to the gold surface. The hydrogen bonding between the pigment molecule and cysteamine causes the aggregation of Au BPs to generate local electromagnetic field enhancement. The influence of the AR and concentration of Au BPs on SERS properties is investigated. The SERS detection of weak-affinity molecules to an extremely low limit shows that the cyst-Au BPs are highly sensitive compared to CTAB-capped Au BPs. The limit of detection (LOD) of allura red as low as 0.1 ppb and that of sunset yellow as low as 1 ppb show that the proposed strategy has many advantages due to its simplicity and fast and rapid detection for the sensitivity analysis of weak-affinity molecules.
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http://dx.doi.org/10.1021/acs.analchem.1c00439DOI Listing
June 2021

Insight of the Influence of Magnetic-Field Direction on Magneto-Plasmonic Interfaces for Tuning Photocatalytical Performance of Semiconductors.

J Phys Chem Lett 2020 Nov 10;11(22):9931-9937. Epub 2020 Nov 10.

College of Sciences, Northeastern University, Shenyang 110004, China.

Boosting photocatalytic performance via external fields is an alternative and effective solution for improving the application performance of existing photocatalysts. Herein, using α-FeO-decorated TiO nanotube arrays as a model, we demonstrate the influence of magnetic field (MF)-direction on the photogenerated charge-carrier transfer behavior at plasmonic metal/semiconductor interfaces. For the first time, the photocatalytic activity is also found to correlate with the plasmonic metal species while applying an external MF. As verified by first-principles calculations, the spin-orbit coupling of metal contributes to the charge-carrier transfer. To highlight the anisotropic MF-tuning effect in practical applications, the as-prepared architecture is applied for photocatalysis-triggered drug delivery. The delivery rate can be remarkably accelerated by ∼38% under a tiny MF (0.4 T) with the proper direction. The findings in this research may provide new insight into designing semiconductor architectures for boosting the photocatalytical performance in an external MF.
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http://dx.doi.org/10.1021/acs.jpclett.0c02927DOI Listing
November 2020

Ordered ring-shaped cracks induced by indentation in metal films on soft elastic substrates.

Phys Rev E 2020 Aug;102(2-1):022801

CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.

Ordered crack patterns contain plentiful physical mechanisms and are useful for technological applications such as lithography, template, and biomimicry. Here we report on ordered multiple ring-shaped cracks induced by indentation in metal films on soft elastic polydimethylsiloxane (PDMS) substrates. It is shown that the indentation triggers the deformation of PDMS substrate and generates a radial tensile stress in the film, leading to the formation of ring-shaped cracks with a nearly uniform spacing. The morphological characteristics and evolution behaviors of the multiple ring-shaped cracks are revealed by optical microscopy, atomic force microscopy, and scanning electron microscopy. Their formation mechanisms are discussed by theoretical analysis based on the fracture mechanics. The report in this work can promote better understanding of the indentation-induced stress anisotropy and mode competition in rigid-film-soft-substrate systems and provide a facile strategy to control the crack patterns by simple mechanical loading.
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http://dx.doi.org/10.1103/PhysRevE.102.022801DOI Listing
August 2020

Structural and cryogenic magnetic properties of rare earth rich RECoIn (RE = Gd, Dy and Ho) intermetallic compounds.

Dalton Trans 2020 Jul 18;49(25):8764-8773. Epub 2020 Jun 18.

Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819, China.

The crystal structure, magnetic properties and magnetocaloric performances of rare earth rich RECoIn (RE = Gd, Dy and Ho) intermetallic compounds are investigated systematically in this work. All compounds in this system crystallize in the orthorhombic NdPdIn-type structure with the Cmmm space group. The stacks of alternate RE and Co/In atomic layers with z = 0, 1 and z = 1/2 along the z-axis constitute the crystal structure. These compounds belong to the REMX family with x = 9 and y = 2, and the ratio of the AlB-type and CsCl-type fragments in a unit cell is y : x, i.e. 2 : 9. The characteristic of multiple magnetic phase transition is revealed with a low magnetic flux density μH of 0.1 T for the present compounds. The ferromagnetic (FM) to paramagnetic (PM) phase transitions of the present compounds around their respective Curie temperatures (T) are all second order phase transitions (SOPTs). Around the T of 86, 37 and 20 K for GdCoIn, DyCoIn, and HoCoIn with a magnetic flux density change ΔμH of 0-7 T, the values of the maximum magnetic entropy change (-ΔS) and temperature averaged entropy change (TEC) with 3 K span are 10.95 and 10.93 J kg K for GdCoIn, 4.66 and 4.64 J kg K for DyCoIn, and 12.29 and 12.09 J kg K for HoCoIn, respectively. The corresponding values of relative cooling power (RCP) and refrigerant capacity (RC) are 538.1 and 405.9 J kg for GdCoIn, 213.9 and 165.9 J kg for DyCoIn, and 475.2 and 357.4 J kg for HoCoIn, respectively.
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http://dx.doi.org/10.1039/d0dt01212bDOI Listing
July 2020

Ag as Cocatalyst and Electron-Hole Medium in CeO QDs/Ag/AgSe Z-scheme Heterojunction Enhanced the Photo-Electrocatalytic Properties of the Photoelectrode.

Nanomaterials (Basel) 2020 Jan 31;10(2). Epub 2020 Jan 31.

Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong 999077, China.

A recyclable photoelectrode with high degradation capability for organic pollutants is crucial for environmental protection and, in this work, a novel CeO quantum dot (QDs)/AgSe Z-scheme photoelectrode boasting increased visible light absorption and fast separation and transfer of photo-induced carriers is prepared and demonstrated. A higher voltage increases the photocurrent and 95.8% of tetracycline (TC) is degraded by 10% CeO QDs/AgSe in 75 minutes. The degradation rate is superior to that achieved by photocatalysis (92.3% of TC in 90 min) or electrocatalysis (27.7% of TC in 90 min). Oxygen vacancies on the CeO QDs advance the separation and transfer of photogenerated carriers at the interfacial region. Free radical capture tests demonstrate that •O, •OH, and h are the principal active substances and, by also considering the bandgaps of CeO QDs and AgSe, the photocatalytic mechanism of CeO QDs/AgSe abides by the Z-scheme rather than the traditional heterojunction scheme. A small amount of metallic Ag formed in the photocatalysis process can form a high-speed charge transfer nano channel, which can greatly inhibit the photogenerated carrier recombination, improve the photocatalytic performance, and help form a steady Z-scheme photocatalysis system. This study would lay a foundation for the design of a Z-scheme solar photocatalytic system.
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http://dx.doi.org/10.3390/nano10020253DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7075152PMC
January 2020

Formononetin attenuates atherosclerosis via regulating interaction between KLF4 and SRA in apoE mice.

Theranostics 2020 1;10(3):1090-1106. Epub 2020 Jan 1.

First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China.

: Atherosclerosis is an underlying cause of coronary heart disease. Foam cell, a hallmark of atherosclerosis, is prominently derived from monocyte-differentiated macrophage, and vascular smooth muscle cells (VSMCs) through unlimitedly phagocytizing oxidized low-density lipoprotein (oxLDL). Therefore, the inhibition of monocyte adhesion to endothelium and uptake of oxLDL might be a breakthrough point for retarding atherosclerosis. Formononetin, an isoflavone extracted from , has exhibited multiple inhibitory effects on proatherogenic factors, such as obesity, dyslipidemia, and inflammation in different animal models. However, its effect on atherosclerosis remains unknown. In this study, we determined if formononetin can inhibit atherosclerosis and elucidated the underlying molecular mechanisms. : ApoE deficient mice were treated with formononetin contained in high-fat diet for 16 weeks. After treatment, mouse aorta, macrophage and serum samples were collected to determine lesions, immune cell profile, lipid profile and expression of related molecules. Concurrently, we investigated the effect of formononetin on monocyte adhesion, foam cell formation, endothelial activation, and macrophage polarization and . : Formononetin reduced and aortic root sinus lesions size. Formononetin enhanced lesion stability by changing the composition of plaque. VSMC- and macrophage-derived foam cell formation and its accumulation in arterial wall were attenuated by formononetin, which might be attributed to decreased SRA expression and reduced monocyte adhesion. Formononetin inhibited atherogenic monocyte adhesion and inflammation. KLF4 negatively regulated the expression of SRA at transcriptional and translational level. : Our study demonstrate that formononetin can substantially attenuate the development of atherosclerosis via regulation of interplay between KLF4 and SRA, which suggests the formononetin might be a novel therapeutic approach for inhibition of atherosclerosis.
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http://dx.doi.org/10.7150/thno.38115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6956811PMC
April 2021

Structural and cryogenic magnetic properties of RENiIn (RE = Pr, Nd, Dy and Ho) compounds.

Dalton Trans 2019 Dec 26;48(48):17792-17799. Epub 2019 Nov 26.

Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819, P. R. China. and Institute of Advanced Magnetic Materials, Hangzhou Dianzi University, Hangzhou 310018, P. R. China.

The crystal structures, magnetic properties and magneto-caloric effects (MCEs) of RENiIn (RE = Pr, Nd, Dy and Ho) compounds were investigated. The results indicate that PrNiIn and NdNiIn compounds have a tetragonal MoFeB-type structure belonging to the P4/mbm space group and undergo a second-order paramagnetic to ferromagnetic (PM to FM) transition at a Curie temperature (T) of 7.5 and 10.5 K, respectively, whereas DyNiIn and HoNiIn compounds have an orthorhombic MnAlB-type structure belonging to the space group Cmmm and possess a magnetic transition from PM to antiferromagnetic (AFM) at a Néel temperature T of 19 and 10.5 K together with a first-order field induced metamagnetic transition, respectively. Moreover, an additional magnetic transition at a lower temperature of around 5.5 K is detected for the HoNiIn compound. A considerable reversible magneto-caloric effect is observed accompanying the magnetic phase transition, and the maximum values of the magnetic entropy change (-ΔS) of the present RENiIn series compounds are determined to be 9.3, 11.5, 6.4 and 11.5 J kg K with a magnetic field change (ΔH) of up to 0-5 T for RE = Pr, Nd, Dy and Ho, respectively.
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http://dx.doi.org/10.1039/c9dt03245bDOI Listing
December 2019

Ultra-fast annealing manipulated spinodal nano-decomposition in Mn-implanted Ge.

Nanotechnology 2019 Feb 30;30(5):054001. Epub 2018 Nov 30.

Harbin Institute of Technology, School of Materials Science and Engineering, 150001, Harbin, People's Republic of China. Laboratory for Space Environment and Physical Science, Research Center of Basic Space Science, Harbin Institute of Technology, 150001, Harbin, People's Republic of China. Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, Bautzner Landstrasse 400, D-01328 Dresden, Germany.

In the present work, millisecond-range flash lamp annealing is used to recrystallize Mn-implanted Ge. Through systematic investigations of structural and magnetic properties, we find that the flash lamp annealing produces a phase mixture consisting of spinodally decomposed Mn-rich ferromagnetic clusters within a paramagnetic-like matrix with randomly distributed Mn atoms. Increasing the annealing energy density from 46, via 50, to 56 J cm causes the segregation of Mn atoms into clusters, as proven by transmission electron microscopy analysis and quantitatively confirmed by magnetization measurements. According to x-ray absorption spectroscopy, the dilute Mn ions within Ge are in d electronic configuration. This Mn-doped Ge shows paramagnetism, as evidenced by the unsaturated magnetic-field-dependent x-ray magnetic circular dichroism signal. Our study reveals how spinodal decomposition occurs and influences the formation of ferromagnetic Mn-rich Ge-Mn nanoclusters.
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http://dx.doi.org/10.1088/1361-6528/aaefb1DOI Listing
February 2019

Study of the Microstructure, Mechanical, and Magnetic Properties of LaFeSiH/Bi Magnetocaloric Composites.

Materials (Basel) 2018 Jun 4;11(6). Epub 2018 Jun 4.

Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110819, China.

We have successfully synthesized LaFeSiH/Bi composites by cold pressing together with vacuum annealing technology, and systematically investigated the microstructure, magnetism, mechanical performance, and magnetocaloric properties. LaFeSiH particles are well surrounded by metallic Bi, without the formation of new phase. The maximum values of the volumetric magnetic entropy change -ΔS are as high as 51, 49, and 35 mJ/cm³K around 263 K, for the composites with 5, 10 and 15 wt % Bi contents, respectively. The maximum value of the compressive strength for LaFeSiH/Bi composites increased continuously from 155 to 358 MPa with increasing Bi content, from 0 to 15 wt %.
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http://dx.doi.org/10.3390/ma11060943DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6025470PMC
June 2018

R383C mutation of human CDC20 results in idiopathic non-obstructive azoospermia.

Oncotarget 2017 Nov 16;8(59):99816-99824. Epub 2017 Sep 16.

Key Laboratory of Medical Reprogramming Technology, Shenzhen Second People's Hospital, The First Affiliated Hospital of Shenzhen University, Guangdong 518035, China.

Idiopathic azoospermia (IA) is a severe form of male infertility due to unknown causes. To investigate relative gene expression in human idiopathic non-obstructive azoospermia, we sequenced all the exons of cell division cycle 20 (CDC20) in 766 patients diagnosed with IA, as well as in 521 normally fertile men. Three novel missense mutations (S72G, R322Q, R383C) of CDC20 were detected and further confirmed by Sanger sequencing. The mRNA levels of securin, cyclin B, cyclin dependent kinase 1 (CDK1), and cyclin dependent kinase 2 (CDK2), which are all targeted for destruction via the anaphase-promoting complex/cyclosome (APC/C) pathway, were detected at relatively high levels using real-time quantitative polymerase chain reaction analysis. This demonstrated that the CDC20 R383C mutation led to dysfunction during the transition from metaphase to anaphase and facilitation of mitotic exit , and caused prolonged mitotic arrest during the cell cycle. This study suggests that a CDC20 R383C mutation may result in the pathogenesis of human IA.
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http://dx.doi.org/10.18632/oncotarget.21071DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5725133PMC
November 2017

Ultraviolet-assisted direct patterning and low-temperature formation of flexible ZrO resistive switching arrays on PET/ITO substrates.

Nanotechnology 2017 Dec;28(48):485707

School of Materials Science and Technology, Xi'an University of Technology, Xi'an, 710048, People's Republic of China.

We demonstrate a low-cost and facile photochemical solution method to prepare the ZrO resistive switching arrays as memristive units on flexible PET/ITO substrates. ZrO solution sensitive to UV light of 337 nm was synthesized using zirconium n-butyl alcohol as the precursor, and benzoylacetone as the complexing agent. After the dip-coated ZrO gel films were irradiated through a mask under the UV lamp (with wavelength of 325-365 nm) at room temperature and rinsed in ethanol, the ZrO gel arrays were obtained on PET/ITO substrates. Subsequently, the ZrO gel arrays were irradiated by deep UV light of 254 and 185 nm at 150 °C, resulting in the amorphous ZrO memristive micro-arrays. The ZrO units on flexible PET/ITO substrates exhibited excellent memristive properties. A high ratio of 10 of on-state and off-state resistance was obtained. The resistive switching behavior of the flexible device remained stable after being bent for 10 times. The device showed stable flexibility up to a minimum bending diameter of 1.25 cm.
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http://dx.doi.org/10.1088/1361-6528/aa91bdDOI Listing
December 2017

Hydrostatic pressure effect on magnetic phase transition and magnetocaloric effect of metamagnetic TmZn compound.

Sci Rep 2017 02 16;7:42908. Epub 2017 Feb 16.

Department of Physics, Faculty of Enginnering, Yokohama National University, Yokohama 240-8501, Japan.

The magnetocaloric effect (MCE) is an intrinsic thermal response of all magnetic solids which has a direct and strong correlation with the corresponding magnetic phase transition. It has been well recognized that the magnetic phase transition can be tuned by adjusting applied pressure. Therefore, we perform the high hydrostatic pressure magnetization measurements (up to 1.4 GPa) on a recently reported giant MCE material of TmZn. The results indicate that the Curie temperature of T increases from 8.4 K at the ambient pressure to 11.5 K under the pressure of 1.4 GPa. The field-induced first order metamagnetic transition is getting weak with increasing pressure, which results in a reduction of MCE. The hydrostatic pressure effect on the magnetic phase transition and MCE in the metamagnetic TmZn is discussed.
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http://dx.doi.org/10.1038/srep42908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5311940PMC
February 2017

High Critical Current Density of YBaCuO Superconducting Films Prepared through a DUV-assisted Solution Deposition Process.

Sci Rep 2016 12 1;6:38257. Epub 2016 Dec 1.

School of Materials Science and Technology, Xi'an University of Technology, Xi'an, Shaanxi 710048, China.

Although the solution deposition of YBaCuO (YBCO) superconducting films is cost effective and capable of large-scale production, further improvements in their superconductivity are necessary. In this study, a deep UV (DUV) irradiation technique combined with a low-fluorine solution process was developed to prepare YBCO films. An acrylic acidic group as the chelating agent was used in the precursor solution. The acrylic acidic group was highly sensitive to DUV light at 254 nm and significantly absorbed UV light. The coated gel films exposed to DUV light decomposed at 150 °C and copper aggregation was prevented. The UV irradiation promoted the removal of the carbon residue and other by-products in the films, increased the density and enhanced the crystallinity and superconductivity of the YBCO films. Using a solution with F/Ba = 2, YBCO films with thicknesses of 260 nm and enhanced critical current densities of nearly 8 MA/cm were produced on the LaAlO (LAO) substrates.
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http://dx.doi.org/10.1038/srep38257DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5131298PMC
December 2016

Comparison of different counting chambers using a computer-assisted semen analyzer.

Syst Biol Reprod Med 2015 27;61(5):307-13. Epub 2015 Jul 27.

a Reproductive Medical Center, People's Hospital of Luohu District , Shenzhen , Guangdong , China.

A routine computer-assisted sperm analysis is an important diagnostic test in the andrology laboratory. To evaluate the accuracy and precision of the different types of counting chambers for human semen analysis in combination with a computer-assisted semen analyzer (CASA), a quality-control study that compared human sperm analysis results obtained using different counting chambers (Makler chamber, disposable 8-cell GoldCyto chamber, disposable 4-cell Leja chamber, a plain glass slide, and a tissue culture dish cover with a 24 × 24 mm(2) coverslip) in conjunction with the CASA systems was performed. Significantly higher counts of sperm concentration were obtained from the reusable Makler chamber than from the other counting chambers. Sperm motility from drop loaded counting chambers was significantly higher than that of capillary-loaded chambers. A plain glass slide and a tissue culture dish cover used with a coverslip showed rather better performance in semen assessment. Disposable chambers are suitable for routine semen analysis with CASA in a diagnostic andrology setting. With the proper workflow and quality control, a plain glass slide and the tissue culture dish cover are acceptable alternatives for routine counting chambers with CASA as necessary. The type of counting chamber should be specified in test reports.
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http://dx.doi.org/10.3109/19396368.2015.1063175DOI Listing
June 2016
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