217 results match your criteria: "College of Material Science and Technology[Affiliation]"

Improved bioconversion of poplar by synergistic treatments with white-rot fungus Trametes velutina D10149 pretreatment and alkaline fractionation.

Bioresour Technol

February 2013

Institute of Biomass Chemistry and Technology, College of Material Science and Technology, Beijing Forestry University, Beijing 100083, China.

Successive treatments with fungus and alkali were proposed to reduce the recalcitrance and improved the enzymatic digestibility of triploid poplar. Biopretreatment with Trametes velutina D10149 for 0, 4, 8, 12 and 16weeks gradually degraded hemicelluloses and lignin, and improved the digestibility of cellulose from 4.0% to 19.

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Nacre biomimetic design--a possible approach to prepare low infrared emissivity composite coatings.

Mater Sci Eng C Mater Biol Appl

January 2013

College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Jiang Jun Road 29, Nanjing 211106, China.

Mimicking the highly organized brick-and-mortar structure of nacre, a kind of nacre-like organic-inorganic composite material of polyurethane (PU)/flaky bronze composite coatings with low infrared emissivity was successfully designed and prepared by using PU and flaky bronze powders as adhesives and pigments, respectively. The infrared emissivity and microstructure of the coatings were systematically investigated by infrared emissometer and scanning electron microscopy, respectively, and the cause of low infrared emissivity of the coatings was discussed by using the theories of one-dimensional photonic structure. The results show that the infrared emissivity of the nacre-like PU/flaky bronze composite coatings can be as low as 0.

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The anatomy and topochemistry in normal and compression wood tracheid cell wall of Pinus bungeana Zucc. were investigated by fluorescence microscopy and confocal Raman microscopy. Using fluorescence microscopy, the severity of compression wood was classed as a mild type for the reason that it did not contain all compression wood features.

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Effect of ionic liquid pretreatment on the structure of hemicelluloses from corncob.

J Agric Food Chem

November 2012

Institute of Biomass Chemistry and Technology, College of Material Science and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China.

Pretreatment is the key to unlock the recalcitrance of lignocellulosic biomass for the productions of biofuels. Ionic liquid pretreatment has drawn increased attention because of its numerous advantages over conventional methods. In this study, corncob was submitted to pretreatments with 1-ethyl-3-methylimadazolium acetate (EMIMAc) and/or H(2)O/dimethyl sulfoxide (DMSO) followed by alkaline extraction to isolate hemicelluloses.

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Colloidal stability of negatively charged cellulose nanocrystalline (CNC) in the presence of inorganic and organic electrolytes was investigated by means of dynamic light scattering and atomic force microscopy. CNC could be well dispersed in distilled water due to the electrostatic repulsion among negatively charged sulfate ester groups. Increasing the concentration of inorganic cation ions (Na(+) and Ca(2+)) resulted in CNC aggregation.

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[Biomimetic mineralization of rod-like cellulose nano-whiskers and spectrum analysis].

Guang Pu Xue Yu Guang Pu Fen Xi

May 2012

College of Material Science and Technology, Beijing Forestry University, Beijing, China.

Cellulose nano-whiskers/nano-hydroxyapatite composite was prepared with biomimetic mineralization using rod-like cellulose nano-whiskers as template. The cellulose nano-whiskers and cellulose nano-whiskers/nano-hydroxyapatite composite were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope-energy dispersive analysis of X-rays (SEM-EDXA). Variation and distribution of carbon, oxygen, calcium, and phosphorus in the composites were studied.

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The prospect of carbon fiber implants in radiotherapy.

J Appl Clin Med Phys

July 2012

College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.

Because of their superior characteristics, carbonaceous materials, which are still at their early stage of development, have garnered significant interest. Because of their low atomic number, carbonaceous orthopedic implants possess radiation properties similar to biological tissues and, therefore, they are more suitable to patients in need of radiotherapy. The effects of stainless steel, titanium, and carbon plates on radiation dose distributions were investigated in this work using Monte Carlo simulations and TLD measurements for 6 MV photon beams.

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[Analysis of pyrolysis process and gas evolution rule of larch wood by TG-FTIR].

Guang Pu Xue Yu Guang Pu Fen Xi

April 2012

College of Material Science and Technology, Beijing Forestry University, Beijing 100083, China.

The weight-loss character and gas evolution rule of larch wood at different heating rates were investigated by TG-FTIR (thermogravimetric analyzer coupled to a Fourier transform infrared spectrometer), and the results were compared with those of larch wood model-component mixture. The main weight-loss area of larch wood was wider than larch wood model-component mixture, and the residual char yield of larch wood (18.97%) was lower than larch wood model-component mixture (29.

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[Preparation and characterization of wood/methylolurea composite with in-situ polymerization].

Guang Pu Xue Yu Guang Pu Fen Xi

November 2011

College of Material Science and Technology, Beijing Forestry University, Beijing 100083, China.

Wood/methylolurea composite was prepared with the in-situ polymerization. The green timber with high moisture content was impregnated by a pulse-dipping machine and then was dried in a hot-press drying kiln. The cross-linking reaction was taken under the heat treatment between the wood modifier and the wood composition, including cellulose, hemicelluloses, and lignin.

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Mercaptopropionic acid (MPA) and cysteamine (Cys) capped CdTe quantum dots (QDs) were successfully prepared and used to investigate the combined influence of surface modification, size distribution, and interaction time on their cytotoxicity in human pancreatic carcinoma (PANC-1) cells. Results indicated that the smaller the size of MPA-CdTe QDs, the higher the cytotoxicity, which could be partly due to the difference of their distribution inside cells. Comparing with MPA-CdTe QDs, Cys-CdTe QDs had better cellular metabolizability and lower cytotoxicity.

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In order to efficiently explore and use woody biomass, six lignin fractions were isolated from dewaxed Caragana sinica via successive extraction with organic solvents and alkaline solutions. The lignin structures were characterized by Fourier transform infrared spectroscopy (FT-IR) and 1D and 2D Nuclear Magnetic Resonance (NMR). FT-IR spectra revealed that the "core" of the lignin structure did not significantly change during the treatment under the conditions given.

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Biocompatible chitosan-coated ZnS quantum dots [CS-ZnS QDs] and chitosan-coated ZnS:Mn2+ quantum dots [CS-ZnS:Mn2+ QDs] were successfully fabricated via a convenient one-step γ-radiation route. The as-obtained QDs were around 5 nm in diameter with excellent water-solubility. These QDs emitting strong visible blue or orange light under UV excitation were successfully used as labels for PANC-1 cells.

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Gamma radiolysis of ceftriaxone sodium for water treatment: assessments of the activity.

Water Sci Technol

November 2011

Department of Nuclear Science and Engineering, College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P.R. China.

As large quantities of antibiotics have been misused in human and veterinary medicine, many different classes of antibiotics with low concentration have been detected in the environmental water. This existence may cause severe ecosystem alterations. Ceftriaxone sodium was employed as the targeted antibiotic to evaluate gamma radiolysis of antibiotics based on the primary elimination test and activity assay.

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[The influence of reference data noise on the NIR prediction results].

Guang Pu Xue Yu Guang Pu Fen Xi

May 2011

College of Material Science and Technology, Beijing Forestry University, Beijing 100083, China.

This article used hemicelluloses content in acacia spp. wood as a case study to demonstrate the influence of noise in the reference data on the results of NIR calibration model. The results indicated that the accuracy of NIR calibration model was affected by the reference data noise.

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[Preparation and properties of wood/modified UF prepolymer composite materials].

Guang Pu Xue Yu Guang Pu Fen Xi

April 2011

College of Material Science and Technology, Beijing Forestry University, Beijing 100083, China.

In the present research, the urea-formaldehyde prepolymer and multilayer hot-press drying were used to modify poplar plantation. The prepolymer was impregnated into cell lumen space by pulse-dipping machine. Then the timbers were compressed and dried by the multilayer hot-press drying kiln.

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Production of xylooligosaccharides by xylanase from Pichia stipitis based on xylan preparation from triploid Populas tomentosa.

Bioresour Technol

July 2011

Institute of Biomass Chemistry and Technology, College of Material Science and Technology, Beijing Forestry University, Beijing, 100083, China.

Xylooligosaccharides (XOS) with DP 2-4 are important synbiotics used as food ingredients based on its prebiotic characteristics. In this work, the production of XOS from lignocellulosic material was performed by combined chemical-enzymatic methods. Xylan was prepared from triploid Populas tomentosa, and bioconverted into XOS by crude xylanase solution obtained from Pichia stipitis.

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[Analysis of decayed wood by fungi with X-ray diffractometry and Fourier transform infrared spectroscopy].

Guang Pu Xue Yu Guang Pu Fen Xi

June 2010

College of Material Science and Technology, Engineering Research Centre of Forestry Biomass Materials & Energy of Ministry of Education, Beijing Forestry University, Beijing 100083, China.

In order to make clear the changes in the micro crystal structures of celluloses and the functional group of main components including cellulose, hemicelluloses and lignin in wood decayed by fungi, the crystallinity, layer spacing d in crystalline unit cell, width of crystallite and functional group of main components of Populus tomentosa Carr wood, which was decayed by Phanerochaete Chysosporium (white-rot) and Postia Placenta (brown-rot) with various durations, for two weeks, four weeks, six weeks, eight weeks and ten weeks, respectively, were investigated by means of X-ray diffraction and FTIR spectroscopy methods. It was concluded that the lattice structures of crystallite in wood cellulose were not destroyed by PC and PP, and the two theta angles and layer spacing d in crystallite were constant, although the decaying treatment times were different for each other when decayed by the same fungi. However, the crystallinity and width of crystallite decreased with the decaying treatment times increasing, and the decaying effects by PP were more significantly than those by PC, which showed that the damage extent of celluloses decayed by PP was greater than that by PC.

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[Extending hemicelluloses content calibration of Acacia spp using NIR to new sites].

Guang Pu Xue Yu Guang Pu Fen Xi

May 2010

College of Material Science and Technology, Beijing Forestry University, Beijing 100083, China.

In this research, hemicellulose contents of 78 wood meal samples of Acacia spp trees grown in Guangxi and another 33 wood meal samples of Acacia spp trees grown in Fujian were measured by wet chemistry. NIR spectra were also collected by a Bruker MPA spectrometer within 4 000-12 500 cm(-1) of wavenumbers using a standard sample cup. Equations were developed using partial least squares (PLS) regression and cross validation for multivariate calibration in this study.

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Preparation of mesoporous silica with pelagic clay and its optical property.

J Nanosci Nanotechnol

March 2010

Key Laboratory of Automobile Materials, Education Ministry, College of Material Science and Technology, Jilin University, Changchun 130026, China.

To obtain mesoporous silica with prime properties, we used pelagic clay as the raw material with the precipitation method. According to the specific surface area (SSA) of production, we optimized the technical conditions and characterized it with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), N2 adsorption, and scanning electron microscopy (SEM). The photoluminescence (PL) and photoluminescence excitation (PLE) of mesoporous silica were tested too.

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Microwave-assisted synthesis of Sb2Se3 submicron tetragonal tubular and spherical crystals.

Nanotechnology

January 2010

Nanomaterials Research Institute, College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China.

Sb(2)Se(3) submicron tetragonal tubes have been prepared by a microwave-assisted polyol method using antimony trichloride and sodium selenite as the Sb and Se precursors. Scanning electron microscopy (SEM) results showed a novel transformation of Sb(2)Se(3) microstructures from submicron tubes to submicron spheres during the microwave heating process. The potential growth mechanism has been investigated by analyzing the samples at different growth stages.

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Tetra (2-isopropyl-5-methylphenoxy) substituted Cu-phthalocyanine nanofibers were obtained in large scale by a simple solvent diffusion method. The sizes of the fibers can be finely tuned under different solvent temperature. FE-SEM micrographs indicate that the length of the fibers changed from several hundreds micrometers to several hundreds nanometers and the width changed from several micrometers to several decade nanometers.

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Silk fibroin coated CdSe quantum dots (SF-CdSe QDs) were successfully synthesized via a one-step gamma-radiation route in an aqueous system at room temperature. The as prepared products were characterized by transmission electron microscope (TEM), energy dispersion spectrum (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-vis) and photoluminescence spectrum (PL). The SF-CdSe QDs were about 5 nm in diameter and exhibited excellent water-solubility and photoluminescence properties.

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[Bio-effects of nano-TiO2 on lungs of mice].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi

August 2009

College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.

To evaluate the acute lung toxicity of intratracheally instilled nano-TiO2 in Kunming mice, healthy adult male Kunming mice were randomly grouped by their body weight (5 mice in each group). The lungs of mice were intratracheally instilled with 1 or 10 mg/kg x bw of nano-TiO2. The control group was intratracheally instilled with the same volume of physiological saline.

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In this work an optimization of the solvent-free acetylation of cellulose with acetic anhydride under microwave heating with iodine as a catalyst was performed. The optimized parameters included the microwave irradiation power from 300 W to 800 W, the reaction time between 5 to 40 min, the reaction temperature from 80 to 130 degrees C, and the amount of iodine from 1 to 15 mol%. The extent of the acetylation was measured by yield and the degree of substitution (DS), which was determined by a back-titration method.

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