Publications by authors named "LiJie Qu"

12 Publications

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Characterization of the structural and dynamic changes of cell wall obtained by ultrasound-water and ultrasound-alkali treatments.

Ultrason Sonochem 2021 Sep 18;77:105672. Epub 2021 Jul 18.

Beijing Key Laboratory of Wood Science and Engineering, College of Material Science and Technology, Beijing Forestry University, No. 35 Tsinghua East Road Haidian District, Beijing, PR China. Electronic address:

It is well-known that ultrasound has been studied for its cavitation, mechanical and thermal effects. As a pretreatment technology, ultrasonic alkali treatment has attracted much attention in the field of biomass biochemical transformation. In this study, the structural and dynamic changes of wood cell walls during ultrasound-water, alkali, and ultrasound-alkali treatments were investigated by stereoscopic microscopy, confocal Raman microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction. The results indicated that the ultrasound-water, alkali, and ultrasound-alkali treatments had the effect of removing extractives from conduits. The uniform self-shrinking samples with shrinkage conduits were obtained by the alkali and ultrasound-alkali treatments. All of the treatments affected the relative content, structure and distribution of the chemical components in the wood cell walls. Compared with water-immersion samples, the relative content of hemicellulose of the treated samples reduced from 32.31% to 7.02% for ultrasound-8% NaOH treated samples. For the signal intensity of lignin, ultrasound-water treated and ultrasound-alkali treated samples displayed a more significant reductions than the alkali treated samples in the cell wall region. The crystal zone and amorphous zone of cellulose coexisted before and after the treatment, for all of the treated samples, and particularly for the ultrasound-assisted treated samples, the crystallinity increased from 38.15% for water-immersion samples to 57.42% for ultrasound-8% NaOH treated samples.
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http://dx.doi.org/10.1016/j.ultsonch.2021.105672DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8339218PMC
September 2021

Effects of Combined Acid-alkali and Heat Treatment on the Physiochemical Structure of Moso Bamboo.

Sci Rep 2020 04 21;10(1):6760. Epub 2020 Apr 21.

Beijing Key Laboratory of Wood Science and Engineering, College of Material Science and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Haidian District, Beijing, 100083, P.R. China.

To improve the performance of bamboo and increase its utilization value, this study aimed at investigating the effects of impregnation pretreatment and thermal treatment on the structural changes of bamboo. The samples were pretreated in sodium hydroxide or zinc chloride solution, and then treated at 160 °C. The pretreated and control samples were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), and Fourier transform infrared spectroscopy (FTIR). The results showed that the cellulose crystallinity and intensity of samples pretreated by ZnCl could be reduced, but the crystal structure remained the same. As for samples pretreated in NaOH, the crystal structure of fiber was destroyed and the crystallinity was increased significantly. High temperature treatment has little effect on the thermal stability of bamboo. However, after treatment with NaOH and ZnCl, the thermal degradation temperature changed obviously and moved to a lower temperature. ZnCl pretreatment had influence on the chemical structure of bamboo, while NaOH pretreatment had greater influence on the chemical structure of bamboo.
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http://dx.doi.org/10.1038/s41598-020-63907-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7174418PMC
April 2020

Injectable hydrogel composed of hydrophobically modified chitosan/oxidized-dextran for wound healing.

Mater Sci Eng C Mater Biol Appl 2019 Nov 29;104:109930. Epub 2019 Jun 29.

Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, PR China. Electronic address:

An injectable hydrogel dressing with multifunctional properties of superior hemostasis, antibacterial activity, tissue adhesive and cytocompatibility is desirable candidate in wound healing. In this study, we developed a novel hydrogel dressing composed of hydrophobically modified chitosan (hmCS) and oxidized dextran (OD). The gelation time, microstructure, injectability, self-healing and rheological properties were characterized. The in vitro ability of the precursor solution of the hydrogels to coagulate heparinized whole blood was confirmed. The in vivo hemostatic activity was demonstrated in a rat hemorrhaging liver model. The antibacterial activity against S. aureus and P. aeruginosa was evaluated in vitro through surface antibacterial test. The corresponding killing efficiencies were up to 95.0% and 96.4% at bacterial concentration of 10 CFU/mL. The cytotoxicity was examined by co-culturing with 3 T3 fibroblast cells. The wound healing functions were further verified with an infected wound model of rat skin. The aforementioned findings demonstrated that the hydrogel with multifunctional activities has potential for hemorrhagic and infected wound healing.
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http://dx.doi.org/10.1016/j.msec.2019.109930DOI Listing
November 2019

Multifunctional Hydrogel Patch with Toughness, Tissue Adhesiveness, and Antibacterial Activity for Sutureless Wound Closure.

ACS Biomater Sci Eng 2019 May 11;5(5):2610-2620. Epub 2019 Apr 11.

Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Sciences, Nankai University, Tianjin 300071, P. R. China.

A multifunctional hydrogel patch with a combination of high toughness, superior adhesion, and good antibacterial effect is a highly desired surgical material. In this study, we developed a novel hydrogel patch composed of poly(ethylene glycol) diacrylate/quaternized chitosan/tannic acid (PEGDA/QCS/TA) based on mussel-inspired chemistry. The physical and biological properties of the hydrogel patch were systematically evaluated in vitro and in vivo. The results indicated that this hydrogel patch possessed compact microstructure, low swelling ratio, tough mechanical properties, good antibacterial activities against and , and excellent dry/wet adhesive ability to a wide range of substrates. The hydrogel patch could also be degraded and absorbed in vivo and used as a sutureless material for wound closure. All these findings demonstrate that the PEGDA/QCS/TA hydrogel patch with multifunctional properties has great potential for application in biomedical fields.
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http://dx.doi.org/10.1021/acsbiomaterials.9b00130DOI Listing
May 2019

Effects of zinc chloride-silicone oil treatment on wood dimensional stability, chemical components, thermal decomposition and its mechanism.

Sci Rep 2019 02 7;9(1):1601. Epub 2019 Feb 7.

Beijing Key Laboratory of Wood Science and Engineering, College of Material Science and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Haidian District, Beijing, 100083, P.R. China.

The hygroexpansion and anisotropy of wood limit its application in construction and wood products industry. Zinc chloride-silicone oil was use to decrease the hygroscopicity and improve the dimensional stability of wood at 80 °C, 140 °C, 160 °C and 180 °C. The effects of the treatment on the dimensional stability, chemical structure, thermal degradation, morphology of wood were evaluated, and the mechanism was determined. Results indicated that the zinc chloride-silicone oil treatment at 80 °C improved the dimensional stability and decreased the hygroscopicity of wood. The tangential, radial, and volumetric swelling coefficients of the treated wood decreased by 9.7%, 33.5%, and 18.2%, respectively, relative to those of the untreated wood. Zinc chloride-silicone oil treatment also changed the chemical structure of wood by degrading the wood components and decreasing the moisture absorption groups. Moreover, zinc chloride-silicone oil treatment significantly influenced the thermal degradation of wood, as samples treated with zinc chloride-silicone oil at 140 °C, 160 °C and 180 °C presented sharp peaks around 511 °C, 501 °C and 473 °C. The control group exhibited a more common derivative thermogravimetric curve with a sharp peak at 375 °C. In addition, the silicone oil could impregnate wood, occlude moisture passage, and prevent the movement of moisture in wood. This method can be applied in building and wood industries to expand the applications of wood products.
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http://dx.doi.org/10.1038/s41598-018-38317-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6367429PMC
February 2019

Effects of the ultrasound-assisted pretreatments using borax and sodium hydroxide on the physicochemical properties of Chinese fir.

Ultrason Sonochem 2019 Jan 17;50:200-207. Epub 2018 Sep 17.

Beijing Key Laboratory of Wood Science and Engineering, College of Material Science and Technology, Beijing Forestry University, No. 35 Tsinghua East Road Haidian District, Beijing, PR China. Electronic address:

This work investigated the physicochemical properties of Chinese fir after ultrasound-assisted pretreatments with borax and sodium hydroxide additives in an aqueous solution. TGA, FTIR, and XRD were used to analyze the thermal degradation processes, changes in chemical structures, and crystallinity of the treated samples, respectively. Additionally, the release of volatiles from wood pyrolysis was measured on-line by the TG-FTIR apparatus. In thermal analysis, all samples showed main degradation stages at 220-500 °C, and alkaline compounds could efficiently shift the process to lower temperatures with lower maximum weight loss rate (MWLR) and more residues. From TG-FTIR, it was observed that CO was the primary gas product from pyrolysis in the alkaline-treated samples, while there were more carbonyl compounds released in the control and deionized water groups. Due to the destruction and removal of hemicellulose and lignin after alkaline treatments, the related peaks changed greatly. Changes in the ester groups caused by saponification also accounted for one of the most significant differences between samples. Moreover, except for the deionized water group without sonication, the crystallinity of the samples increased from 6.34% to 11.29%. Overall, comparing the samples treated with or without ultrasound, the results showed that the ultrasound treatment did influence the samples' physicochemical properties, and its' effects varied by the basicity of the solution. This in-depth investigation offers a better understanding of ultrasound-assisted and alkaline pretreatments of wood materials.
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http://dx.doi.org/10.1016/j.ultsonch.2018.09.017DOI Listing
January 2019

PNIPAM-MAPOSS Hybrid Hydrogels with Excellent Swelling Behavior and Enhanced Mechanical Performance: Preparation and Drug Release of 5-Fluorouracil.

Polymers (Basel) 2018 Jan 31;10(2). Epub 2018 Jan 31.

Key Laboratory of Automobile Materials, Ministry of Education, College of Materials Science and Engineering, Jilin University, Changchun 130022, China.

Poly(-isopropylacrylamide) (PNIPAM) is a widely-studied polymers due to its excellent temperature sensitivity. PNIPAM-MAPOSS hybrid hydrogel, based on the introduction of acrylolsobutyl polyhedral oligomeric silsesquioxane (MAPOSS) into the PNIPAM matrix in the presence of polyethylene glycol, was prepared via radical polymerization. The modified hydrogels exhibited a thick, heterogeneous porous structure. PEG was used as a pore-forming agent to adjust the pore size. MAPOSS reduced the swelling ratios of gels, and decreased the LCST, causing the hydrogels to shrink at lower temperatures. However, its hydrophobicity helped to improve the temperature response rate. The incorporation of rigid MAPOSS into the polymer network greatly increased the compressive modulus of the hydrogel. It is worth noting that, by adjusting the amount of MAPOSS and PEG, the hydrogel could have both ideal mechanical properties and swelling behavior. In addition, hydrogel containing 8.33 wt % MAPOSS could achieve stable and sustained drug release. Thus, the prepared PNIPAM-MAPOSS hybrid hydrogel can serve as drug carrier for 5-fluorouracil and may have potential application in other biomedical fields.
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http://dx.doi.org/10.3390/polym10020137DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6414838PMC
January 2018

Intravoxel incoherent motion diffusion-weighted imaging for the assessment of renal fibrosis of chronic kidney disease: A preliminary study.

Magn Reson Imaging 2018 04 5;47:118-124. Epub 2017 Dec 5.

Department of Radiology, Nantong Second People's Hospital, Nantong 226000, People's Republic of China. Electronic address:

Purpose: To investigate the potential of Intravoxel incoherent motion diffusion-weighted imaging(IVIM-DWI) for the assessment of renal fibrosis in chronic kidney disease (CKD), using histopathology as a reference standard.

Methods: Eighty-five CKD patients and twenty healthy volunteers were recruited in this study. IVIM-DWI was performed in all of the participants, and all of the CKD patients underwent renal biopsy. The mean values of the true diffusion coefficient (D), pseudo diffusion coefficient (D*) and perfusion fraction (f) in the renal cortex and medulla were compared between the CKD patients and healthy volunteers. The Spearman correlation coefficient was calculated to assess the relationship between the D, D*,f values and the estimated glomerular filtration rate (eGFR), serum creatinine level (SCr), 24h urinary protein level (24h-UPRO), histopathological fibrosis scores.

Results: The D, D* and f values were significantly lower in medulla than in the cortex for all of the participants. All of the IVIM parameters were significantly lower in the CKD patients than in the healthy controls. In the CKD patients, a significant negative correlation was found between the renal parenchymal D, D*,f values and the 24h-UPRO, as well as between the renal parenchymal D, f values and the SCr. There was a significant positive correlation between all of the IVIM parameters and the eGFR. All of the IVIM parameters exhibited a significant negative correlation with the histopathological fibrosis score.

Conclusion: IVIM-DWI shows great potential in the noninvasive assessment of renal fibrosis in CKD.
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http://dx.doi.org/10.1016/j.mri.2017.12.010DOI Listing
April 2018

Chronic kidney disease: Pathological and functional evaluation with intravoxel incoherent motion diffusion-weighted imaging.

J Magn Reson Imaging 2018 05 21;47(5):1251-1259. Epub 2017 Sep 21.

Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen, P.R. China.

Background: Because chronic kidney disease (CKD) is a worldwide problem, accurate pathological and functional evaluation is required for planning treatment and follow-up. Intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) can assess both capillary perfusion and tissue diffusion and may be helpful in evaluating renal function and pathology.

Purpose: To evaluate functional and pathological alterations in CKD by applying IVIM-DWI.

Study Type: Prospective study.

Subjects: In all, 72 CKD patients who required renal biopsy and 20 healthy volunteers.

Field Strength: 1.5T.

Assessment: All subjects underwent IVIM-DWI of the kidneys, and image analysis was performed by two radiologists. The mean values of true diffusion coefficient (D), pseudo diffusion coefficient (D*), and perfusion fraction (f) were acquired from renal parenchyma. Correlation between IVIM-DWI parameters and estimated glomerular filtration rate (eGFR), as well as pathological damage, were assessed.

Statistical Tests: One-way analysis of variance (ANOVA), paired sample t-test and Spearman correlation analysis.

Results: The paired sample t-test revealed that IVIM-DWI parameters were significantly lower in medulla than cortex for both patients and controls (P < 0.01). Regardless of whether eGFR was reduced, ANOVA revealed that f values of renal parenchyma were significantly lower in patients than controls (P < 0.05). Spearman correlation analysis revealed that there were positive correlations between eGFR and D (cortex, r = 0.466, P < 0.001; medulla, r = 0.491, P < 0.001), and between eGFR and f (cortex, r = 0.713, P < 0.001; medulla, r = 0.512, P < 0.001). Negative correlations were found between f and glomerular injury (cortex, r = -0.773, P < 0.001; medulla, r = -0.629, P < 0.001), and between f and tubulointerstitial lesion (cortex, r = -0.728, P < 0.001; medulla, r = -0.547, P < 0.001).

Data Conclusion: IVIM-DWI might be feasible for noninvasive evaluation of renal function and pathology of CKD, especially in detection of renal insufficiency at an early stage.

Level Of Evidence: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1251-1259.
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http://dx.doi.org/10.1002/jmri.25861DOI Listing
May 2018

[Effect of different surface treatments on bonding strength of composite resin to commercially pure titanium].

Hua Xi Kou Qiang Yi Xue Za Zhi 2013 Feb;31(1):13-6

Dept. of Prosthodontics, The Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.

Objective: To investigate the effectiveness of different surface treatments that could promote the bond strength of composite resin to commercially pure titanium.

Methods: The 24 casting pure titanium specimen were randomly divided into four groups: Smooth group, rough group, acid etching smooth group, acid etching rough group. Each group had six specimens. In the different groups, the specimens were treated respectively under different surface treatments. The specimens of rough group was sandblasted, the acid etching smooth group was treated by acid etching, the acid etching rough group was treated by acid etching after sandblasting, the smooth group had no treatment. After surface treatment, the casting pure titanium specimens that were veneered by composite resin became titanium-composite resin specimen. Then the bond strengths were evaluated by universal testing machine and the surfaces were observed by scanning electron microscope including titanium surface appearance and titanium surface appearance of different groups after shear test.

Results: The bond strengths of smooth group, rough group, acid etching smooth group, acid etching rough group were (3.08 +/- 0.45), (6.05 +/- 0.74), (6.27 +/- 0.80), (10.16 +/- 0.82) MPa, respectively. The statistical analysis showed that the bond strengths in rough group, acid etching smooth group, acid etching rough group were higher than in smooth group (P < 0.01). The highest bond strength was the acid etching rough group. There were no significant differences in the bond strength between rough group and acid etching smooth group (P > 0.05). There were some different titanium surface appearances in each group before and after testing.

Conclusion: Titanium surface treatment of sandblasting and etching can improve the bond strength between titanium and composite resin. The pre-treatment of sandblasting before etching is an effective modification method of titanium for bonding to composite resin.
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February 2013

Study of synthesis of nano-hydroxyapatite using a silk fibroin template.

Biomed Mater 2010 Aug 3;5(4):041002. Epub 2010 Aug 3.

Provincial Key Laboratory of Biomaterials, Jiamusi University, Jiamusi 154007, People's Republic of China.

Nano-hydroxyapatite (HA) was directly synthesized on a silk fibroin (SF) template using the property of SF being soluble in a concentrated CaCl(2) solution as a HA source of calcium at pH 7.4 and room temperature. The microstructure and bonding state were investigated by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry-thermogravimetry analysis (DSC-TG) and transmission electron microscopy (TEM). The results indicated that the HA crystals were poorly crystallized with a rod-like shape of 20-60 nm length and 10-20 nm diameter. Strong molecular interactions and chemical bonds might be present between SF and HA. There were other nucleation sites such as carbonyl (-C-O) and amine (-N-H-) groups on SF molecules besides the carboxyl (-COOH) and hydroxyl (-OH) groups previously reported. During the formation of HA, the coordination action between specific functional groups on SF and calcium ions (Ca(2+)) played an important role. The crystallinity of HA was improved and had an orientation growth along (0 0 2) at the presence of SF, resulting in a structure similar to natural bone. It was concluded that SF could regulate the structure and morphology of HA effectively.
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http://dx.doi.org/10.1088/1748-6041/5/4/041002DOI Listing
August 2010

Preparation and biological properties of PLLA/beta-TCP composites reinforced by chitosan fibers.

Biomed Mater 2008 Jun 15;3(2):025004. Epub 2008 Apr 15.

School of Materials Science and Engineering, Harbin Institute of Technology, Heilongjiang Province, 150001, People's Republic of China.

Chitosan fibers were introduced into a poly(L-lactic acid)/beta-tricalcium phosphate (PLLA/beta-TCP) matrix as reinforcement to prepare scaffold materials for bone tissue engineering with adequate initial strength and a feasible degradation rate. The structure and morphology of the composites were observed by a scanning electron microscope (SEM). The porosity of the composites was tested by Archimedes' method. The mechanical property of the composites was measured. Simulated body fluid (SBF) experiments were conducted to assess the bioactivity of the composites. The chemical components of resultants on surfaces were analyzed by Fourier transform infrared spectroscopy (FTIR). The influence of the addition of chitosan fibers on the pH value, mass loss rate and structure of samples during immersion was also discussed. The results show that the initial compressive strength reaches 16.07 MPa when the composites prepared have a porosity of 36%. With the degradation of chitosan fibers, an interconnected structure is earlier formed in situ throughout the scaffolds, which is favorable for new bone ingrowth. The compressive strength of the composite decreases flatly and still maintains at 5.28 MPa after immersion in SBF for 24 days. Meanwhile, the formation of a layer of bone-like apatites on the surfaces of the samples indicates good biological activity. It is concluded that the composites have a promising prospect as bone tissue engineering materials.
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http://dx.doi.org/10.1088/1748-6041/3/2/025004DOI Listing
June 2008
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