Abstract: Flash pyrolysis of cellulose is done on the laser pyrolysis experiment device, from which some water-loving yellow substances are collected, which is confirmed as active cellulose. HPLC analysis shows that the chief constituent of this yellow substances are glucose, fructose and oligosaccharide, and whose yield are determined. The research indicates that: at high-radiation power, glucose is not the only production decomposing from oligosaccharide, and there is another production decomposing from oligosaccharide which will compete against glucose. At last, the mechanism of the first pyrolysis of cellulose is analysed.
Abstract: In the experiment, Bergenla tianquanensis in Tianquan County of Sichuan Province is used as materials for tissue culture, The effect of Polyvinylpyrrolidone (PVP) and Activated carbon（AC）and gibberellin (GA3) on Peroxidase (POD) Activities in the browning of bergenla leaves in the culture process was investigated and researched. The results showed that the inhibition effect of GA3 on the browning of Bergenin was better than PVP and AC.
Abstract: The variation regulation of five bioactive components including carnosic acid (CA), carnosol (CO), rosmarinic acid (RA), oleanolic acid (OA) and ursolic acid (UA) in rosemary leaves and extraction procedure was studied. The effects of rosemary sources, steam distillation time, activated carbon dosage and storage time of extraction solution on variation regulation of bioactive components were discussed in detail.
Abstract: Compositing with starch is an effective way to lower the cost of the poly (lactic acid)(PLA)-based biodegradable materials, while the compatibility of these two phases needs to be enhanced. Here reports an improvement based on vacuum heating treatment(VHT), hence a solid-phase esterification between PLA and crosslinked starch（CST） is enhanced. This research also studied the impact by esterified catalysts and starch proportion on thermal stability, surface morphology and mechanical properties of the composite. The result indicated that VHT shows positive effect on all aspects. Especially, sample with 20% CST shows optimized tensile strength of 62.6 MPa, and elongation at break was as high as 69.8%.
Abstract: Ilex Cornuta L is an important medicinal plant. Flavonoid compounds are its main biological compontents. AlCl3 method was identified as the appropriate determination method for total flavonoids content of extract obtained from the leaves of Ilex Cornuta L.. The proposed method was validated by the linearity, reproducibility, and recovery experiments. Good linearity was observed with the regression coefficient(R2= 0.999). The recovery rate was in the range of 94.9% and 110.0%, and the relative standard deviation was 2.8%, which indicated that the proposed method was credible. In addition, the extraction parameters including Ethanol concentration, solid-liquid ratio, extraction time and extraction times were optimized by means of an orthogonal design.
Abstract: Amorphous rice husk silica with purity of 99.3% and the specific surface area value of 212 mP2P/g was obtained by burning the dilute HCl treated rice husk at 600°C. After being modified with γ-glycidyloxipropyltrimethoxysilane (KH-550), silica particles with size ranging from 30 to 50 nm were obtained and subsequently used as filler to prepare epoxy-based nanocomposites with 0, 1, 3, 5 and 10 wt% silica content. The mechanical properties of the nanocomposites were characterized in terms of tensile and flexural test. The morphologies of fracture surfaces of nanocomposites were investigated by scanning electron microscopy (SEM). Depending on the silica content, the stiffness, strength and toughness of the nanocomposites can be increased more or less compared with neat resin.
Abstract: High surface area activated carbon was prepared from waste tobacco after extracting nicotine with microbial enzymatic and chemical activation. Surface properties of the prepared carbons were performed using nitrogen adsorption, and the adsorption behavior of the prepared carbons under different operation conditions on methyl orange was investigated by a batch adsorption experiment. The experimental results show that: using waste tobacco 5.0035g and white- rot fungi volume is 2.0ml, under the conditions of enzymatic time of 36h, activation temperature at 600°C and activation time of 2h, the concentration of ZnCl2 activation is 20%,The BET surface area of carbons prepared reach 1356.53m2/g, the average aperture is3.78nm, and the hole dimension is0.17 ml/g. The adsorption amount on methyl orange of 43mg/L reach 4979.31mg/g, and it show high adsorption capacity.
Abstract: We mainly characterized the compositions and basic properties of pyrolysis liquids of waste wood-based board in this study which can be a basic research for a further study of the possible application of the liquids. Compositions of pyrolysis liquids of wood-based board were analyzed by gas chromatography mass spectrometry (GC-MS). Basic properties of pyrolysis liquids including moisture content, density, diopter, pH and acidity were tested in the experiment. Results from GC-MS analysis show that pyrolysis liquids were influenced a lot by the nitrogen compounds transferred from urea formaldehyde (UF). Pyrolysis liquids are weak acetic to weak alkaline influenced by the pyrolysis compounds of UF adhesive. There are also some differences in properties between the pyrolysis liquids of medium density fiberboard (MDF) and particle board (PB). Future studies should be carried out to study the specific compositions and possible application of the liquids.
Abstract: The structural evolution of rice husk char particles during steam gasification was studied. The chars were characterized by ultimate analysis, field emission scanning electron microscope (FESEM), N2 isothermal adsorption/desorption method and X-ray diffraction (XRD). The results indicate that with the development of gasification, the H/C atomic ratio always increases, but the O/C atomic ratio and oxygen content decrease firstly, then increase and decrease finally. As the conversion increases, the K, Ca, Na and Mg contents in rice husk chars first increase then decrease and the conversion values corresponding to their maximum peaks are different. The change trend of the micropore volume is similar to that of the surface area during gasification. As the degree of gasification reaction deepens, biomass chars become more ordered.
Abstract: In this study, orange peel (OP) was modified by KCl to prepare a novel orange peel adsorbent named as KOP. The adsorption behaviors of KOP for five heavy metals (Cu2+, Cd2+, Pb2+, Zn2+, Ni2+) were studied. The effects of pH, adsorption time and metal ion concentration on single heavy metal solution adsorption by KOP were investigated. All adsorption processes can attain equilibrium with 20min and kinetics data of five heavy metal ions were fitted to pseudo-second-equation; the maximum adsorption capacities for Cu2+, Cd2+, Pb2+, Zn2+ and Ni2+ were calculated as 59.77, 125.63, 141.84, 45.29 and 49.14 mg/g, respectively. Recycle and reuse experiments indicate that KOP could be used for more than 10 cycles. The effect of coexist metal ions on adsorption can be neglected.