Treatment of sugi （Cryptomeria japonica D.） sapwood with aqueous solution of acetic acid

Sugi sapwood samples were processed with aqueous solution of acetic acid in order to find the response of the weight of sugi sapwood and the treatment of aqueous solution of acetic acid. The result showed that loss of weight for the treated sugisapwood was about equal to yield of extracts from sugi sapwood, and increased with the increment of the concentration of aqueous solution of acetic acid. Fourier transform infrared spectroscopy spectra changes of the treated sugi wood and extracts from sugi sapwood were analyzed by FT-IR spectroscopic technique. Increasing tendency of absorption intensities of the stretching vibration at 3 400 cm^-1 of hydroxyl group (OH) and C=C in lignin stretching vibration at 1510 cm^-1 of benzene ring inlignin were observed from FT-IR of the treated sugi sapwood. From FT-IR spectra of extracts from sugi sapwood by aqueoussolution of acetic acid, the dissolution of lignin was observed during the treatment with 30% acetic acid solution aqueous.     

Postia placenta decay of acetic anhydride modified wood – Effect of leaching

Abstract

It is well established that acetylation of wood by the use of acetic anhydride is able to impart a significant degree of decay resistance. The aim of this work was to study how a standardized leaching procedure with water (EN 84) affected the degradation of acetic anhydride modified samples by the brown rot fungi Postia placenta compared to no leaching prior to incubation. Three different levels (low, medium, and high) of acetic anhydride modified Southern yellow pine (SYP; Pinus spp.) were tested. The samples were harvested after 4 and 28 weeks. We compared changes in mass loss, wood moisture content, fungal DNA, and gene expression from five genes. If leaching changes the acetylated samples and makes them more susceptible for fungal deterioration, the expected effect would be higher levels of these parameters. Generally, leaching resulted in few differences between leached and nonleached samples at low levels of acetylation, while no changes were found for the highest acetylation level. No differences were found in gene expressions after 28 weeks. The possible protection of acetylated wood against oxidative fungal degradation is suggested to be interpreted in combination with the lowered wood moisture content.     

Mechanical properties of kenaf fiber–cement composites containing kenaf gamma-ray grafted with acrylamide

Kenaf fibers have excellent properties and possess the potential to be outstanding reinforcing fillers in cement. The grafting of acrylamide to kenaf fibers is important in improving the compatibility between the fibers and the cement. Acrylamide was grafted onto kenaf fibers using gamma-ray radiation. The radiation dose ranged from 20 to 100 kGy, and the dose rate was 10 kGy/h. The degree of grafting increased with increased radiation doses. FT-IR analysis revealed an increase in amide content after gamma-ray-radiation-induced grafting, further evincing the attachment of acrylamide to the kenaf fibers. SEM images showed evidence of acrylamide grafting to the fiber surface. Contact angle measurements on individual fibers taken before and after grafting demonstrated changes in wettability. The mechanical properties of the gamma-ray-grafted kenaf fiber–cement composites were superior to those of the ungrafted kenaf fiber–cement specimens.     

Development, manufacture and application of Beta-Cypermethrin aqueous capsule suspension

The optimal formula of Beta-Cypermethrin aqueous capsule suspension was screened out through the experiment,preparation and manufacture of basic formulas, which has no sedimentation, suspended drops of oil, peels and agglomerating and the diameter of capsule is in range of 10-30μm, conformed to the technical requirement. The aftereffect of the 3.3% Beta-Cypermethrin aqueous capsule suspension which was manufactured according to the optimal formula was up more than 25 days. The experiments on controlling the larvae of Dendrolinmus superans Butler and the adults of Xylotrechus rusticus L were carried out with different concentrations of this chemical. The death rate reached 80% when 250 times solution of the chemical was sprayed on stem to control the larvae of D. superans. For control of the adults of X. rusticus, 200, 400 and 600 times solution of the chemical were applied and their control effects (death rate) reached 85.23%, 74.21% and 66.59% respectively. Two kinds of solution (200 times and 300 times) of the chemical were used to control the larvae of D. superans in large area, and the control effect for both concentrations was over 90%.     

Molecular sieving behavior of carbonized wood: selective adsorption of toluene from a gas mixture containing α-pinene

The adsorption properties of wood carbonized at various temperatures were investigated using a mixed gas containing toluene and α-pinene. Hinoki (Chamaecyparis obtusa) samples carbonized at 500°–1100°C were exposed to gas mixtures of toluene and α-pinene at 20°C. The samples carbonized at 500°–700°C only adsorbed toluene, whereas those carbonized at 800°–1100°C adsorbed both toluene and α-pinene. Analysis of the surface structure of the carbonized wood by nitrogen adsorption at liquid nitrogen temperature indicated that the sample carbonized at 700°C had micropores mainly 0.6 nm in diameter and few mesopores, whereas the samples carbonized at 900°C and 1100°C had mesopores and micropores larger than 0.8 nm in diameter. With the sample carbonized at 700°C, the flat-shaped toluene molecules could probably penetrate into the narrower pores, 0.8 nm in diameter, whereas the bulky globular-shaped α-pinene molecules could not. Carbonization at temperatures higher than 900°C probably enlarged the pore size and thereby reduced the selectivity of adsorption. The results revealed that wood carbonized below activation temperature has a unique flat-pore structure that seems to work as a kind of molecular sieving carbon, successfully removing only the harmful volatile organic compound (VOC), toluene, and leaving behind a pleasant aroma of α-pinene in the atmosphere.     

Development of Social Forestry with Chinese Characteristics

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Cultivation of Poplars with Medium Rotation Times:Aspects of E

ＣｕｌｔｉｖａｔｉｏｎｏｆＰｏｐｌａｒｓｗｉｔｈＭｅｄｉｕｍＲｏｔａｔｉｏｎＴｉｍｅｓ：ＡｓｐｅｃｔｓｏｆＥｃｏｌｏｇｙａｎｄＰｒｏｄｕｃｔｉｏｎＢｉｏｌｏｇｙＡｌｏｙｓＨüｔｅｒｍａｎｎＡｂｔｅｉｌｕｎｇｆüｒＴｅｃｈｎｉｓｃｈｅＭｙｋｏｌｏｇｉｅ...     

Visualization of Cellulose Microfibrils of Phyllostachys pubescens Fibers with Atomic Force Microscope

Atomic force microscope(AFM) was used to investigate the arrangement of cellulose microfibrils (CMF) in Moso bamboo (Phyllostachys pubescens) fibers. Two methods of sample preparation were used here for different purposes. The first method was chemical maceration with a mixture of hydrogen peroxide and glacial acetic acid, through which the obtained fibers were suitable for observing the orientation of CMF in the primary wal1. The other method was to prepare tangential microtomed sections with a thickness o...     

Comparison of water absorption and mechanical properties of wood–plastic composites made from polypropylene and polylactic acid

Abstract

This study focuses on the water absorption and mechanical properties of composites made from softwood sawdust and plastics, such as virgin and recycled polypropylene and polylactic acid (PLA). The composites were processed by extrusion, and their properties were investigated by a water immersion test, mechanical tests and a cyclic test for moisture resistance. Scanning electron microscopy was used to study the morphology of the fracture surfaces of the composites. The composites made with recycled polypropylene had the lowest water absorption and thickness swelling of the studied composites. The PLA composites made with heat-treated sawdust showed the highest flexural strength. Of the polypropylene based composites, virgin polypropylene resulted in composites with higher flexural strength. The Charpy impact strength of the composites was found to have an inverse trend compared to flexural strength. Cyclic treatment of the studied composites resulted in 20–60% loss of flexural strength, depending on type of composite.     

Analysis of genetic relationship in 12 species of Section Strobus with ISSR markers

Genetic relationship of 12 species of Section Strobus was analyzed with ISSR markers. 117 loci were detected with 12 ISSR primers. Percentage of polymorphic bands （PPB） varied from 5.93% to 19.92%. P. pumila had the highest levels of genetic differentiation and P. flexilis had lowest. Total genetic diversity （Hr） of 12 species in Section Strobus was 26.21%, of which intraspecific genetic diversity （Hs） was 7.66%, and interspecific genetic diversity （DST） was 18.55%, and the genetic variation in interspecies accounted for 70.78% of the total genetic diversity. According to the cluster results of genetic distance, the 12 species were classified into two groups. The first group included P. griffithii, P.armandi, P. fenzeliana, P. kwangtungensis, P. strobus, P. monticola and P. wangii. The second group included P. albicaulis, P pumila, P. flexilis, P. sibirica and P koraiensis.     

Nondestructive determination of paper properties of Populus × euramericana with near infrared spectroscopy

Five Populus x euramericana wood samples representing three different sites were selected and nearinfrared （NIR） spectra were obtained. For these sections, basis weight, brightness and three mechanical properties （tensile index, tearing index and bursting index） were determined by standard analytical methods. Calibrations were developed for each paper property using the NIR spectra, data on paper properties, using partial least squares （PLS） regression. The results show that the coefficients of correlation of calibration and validation for basis weight were 0.8824 and 0.8299, respectively; the standard error of calibration （SEC） and prediction （SEP） were 1.150 and 1.170, respectively. In testing for brightness, the correlation coefficient of calibration was 0.9621 and for validation 0.9612, while the SEC and SEP were 0.997 and 1.300, respectively; paper brightness and NIR spectroscopy were highly correlated. NIR spectroscopy can be used to predict tensile, tearing and bursting indices of paper samples rapidly. We found that the paper properties fitted by NIR and GB methods were highly correlated. The coefficients of correlation of calibration and validation for basis weight exceeded 0.8000, while the SEC and SEP were very small. These results reveal that the five paper properties of Populus x euramericana and those predicted by the NIR model were highly correlated. We conclude that the NIR models can be used for the prediction of paper properties.     

Growth of Populusxeuramiricana ‘Neva＇ with Stump Grafting

通过对欧美107杨胸径、树高、蓄积生长量的调查与分析,结果表明：欧美107杨嫁接法造林与常规法造林相比,生长状况具有明显的优势;3、7、11年生欧美107杨,嫁接法造林和常规法造林相比,平均胸径差异为6．2、11．2、8．7cm,差异在50％以上;平均树高差异为6、10、6．3m,第3年和第7年差异率在100％以上,材积在第7年和第11年差异率在100％以上,差异明显。     

The effects of phenolic acid on nitrogen metabolism in Populus 3 euramericana ‘Neva’

The declines in soil fertility and productivity in continuously cropped poplar plantations are related to phenolic acid accumulation in the soil.Nitrogen is a vital life element for poplar and whether the accumulation of phenolic acid could influence nitrogen metabolism in poplar and thereby hinder continuous cropping is not clear.In this study, poplar cuttings of Populus × euramericana‘Neva’ were potted in vermiculite, and phenolic acids at three concentrations(0 X, 0.5 X and 1.0 X) were added according to the actual content(1.0 X) in the soil of a second-generation poplar plantation.Each treatment had eight replicates.We measured gas exchange parameters and the activities of key enzymes related to nitrogen metabolism in the leaves.Leaf photosynthetic parameters varied with the concentration of phenolic acids.The net photosynthetic rate(P_N) significantly decreased with increasing phenolic acid concentration, and non-stomatal factors might have been the primary limitation for P_N.The activities of nitrate reductase(NR), glutamine synthetase(GS) and glutamate synthase(GOGAT), as well as the contents of nitrate nitrogen, ammonium nitrogen, and total nitrogen in the leaves decreased with increasing phenolic acid concentration.This was significantly and positively related to P_N(P0.05).The low concentration of phenolic acids mainly affected the transformation process of NO_3~- to NO_2~-, while the high concentration of phenolic acids affected both processes, where NO_3~- was transferred to NO_2~- and NH_4~+ was transferred to glutamine(Gln).Overall, phenolic acid had significant inhibitory effects on the photosynthetic productivity of Populus × euramericana‘Neva’.This was probably due to its influence on the activities of nitrogen assimilation enzymes, which reduced the amount of amino acids that were translated into protein and enzymes.Improving the absorption and utilization of nitrogen by plants could help to overcome the problems caused by continuous cropping.     

Productive test of a newly drying technology of veneer： intermittent-contact drying of veneer with flexible screen belt

A newly drying technology, intermittent-contact drying of veneer with flexible screen belt (ICD-fbs), was invented and used in poplar veneer drying. Productive test was carried out for validating the practical use of this drying method. The test result shows that to dispose flexible screen belts on the two sides of hot board could help steam discharge remarkably. The veneer dried using ICD-fsb method had smooth and level surface, less deformation and warping, even moisture content, and high utilization rate. The time for opening hot board to discharge steam,which, early or late, is a key to obtain good drying result, was determined at the time when the core‘s temperature of veneer reaches 100℃ (vaporization). Using ICD-fsb method, the shrinking rates in tangent of veneer were from 1.90% to 2.26% for veneer of 0.4 mm in thickness,2.49% to 4.50% for veneer of 1 mm in thickness and 1.34% to 3.30% for veneer of 1.7 mm in thickness, which are much lower than the results obtained by other drying methods. The method of ICD-fsb offers a reliable technological guarantee for solving the deformation problem of veneer drying, especially the deformation of wood from quick-growing plantation.     

Physical and Mechanical Properties of Flakeboard Reinforced with Bamboo Strips

The objective of this study was to investigate the physical and mechanical performance of flakeboard reinforced with bamboo strips. The study investigated three different bamboo strip alignment patterns and an experimental control. All panels were tested in static bending both along parallel and perpendicular to the lengths of the bamboo strips. Internal bond strength (IB), thickness swelling (TS), linear expansion (LE), and water absorption (WA) were also examined. As expected, modulus of rupture (MOR) and modulus of elasticity (MOE) were substantially greater for all three experimental panel types as compared to the control group. LE was also improved for all three experimental panel groups. The bamboo strip alignment patterns had no significant effect on TS, WA and IB. The sample means for MOR, MOE and LE tested perpendicular to the bamboo strip lengths yielded slightly lower mean values than corresponding samples tested parallel to the bamboo strips lengths. This difference in mechanical properties is largely attributed to low panel density in the failure zones.     

Biological performance,water absorption,and swelling of wood treated with nano-particles combined with the application of Paraloid B72~

We evaluated fungal decay and mold resistance,leaching, and water absorption of nano-compounds and Paraloid B72~(PB72) in treated wood specimens to develop new methods of consolidation by combining nanoparticles and consolidants. Scots pine wood specimens were treated with dispersions of nano-Cu O, nano-Zn O,nano-B_2O_3, nano-Ti O_2, and nano-Ce O_2. PB72 treatments of nano-particle-treated wood specimens were then carried out by either vacuum or immersion for 24 h. Previously,decayed wood specimens were also consolidated with the nano-compounds and PB72. PB72 treatments reduced element release from treated wood specimens. Nearly all nano-compounds ? PB72 treatments increased the biological performance of treated wood specimens against decay fungi tested. PB72-only treated wood specimens had the highest weight losses in decay tests. No improvements were obtained in mold resistance tests when the nanocompounds and PB72 were combined. In nano-compoundonly treatments, unleached specimens showed slightly lower water absorption values compared to untreated control specimens. Incorporation of PB72 into nano-compound-treated wood specimens resulted in considerably lower water absorption and volumetric swell. In previously decayed specimens treated with the nano-compounds and PB72 solution, water absorption after 2-h immersion declined compared to control specimens.     

Biosorption of methylene blue from aqueous solutions on β-cyclodextrin grafting wood flour copolymer: kinetic and equilibrium studies

The preparation, characterization, and environmental application of β-cyclodextrin/citric acid/wood flour (β-CD/CA/WF) graft copolymer wood-based biosorbent for methylene blue (MB) biosorption were investigated in this paper. The Fourier transform infrared spectroscopy and the technique of phenolphthalein probe were used to characterize the grafting β-CD. Furthermore, the biosorption behavior of MB on β-CD/CA/WF graft copolymer was studied under various conditions of pH, contact time, and initial MB concentration. The results indicated that the biosorption of MB was dependent on both the initial MB concentration and the initial pH. Langmuir isotherm model fitted the isotherm data better than the Freundlich model. The adsorption kinetics followed the pseudo-second-order kinetic model, and intraparticle diffusion was one of the effective rate-controlling steps for the entire biosorption period. Equilibrium and kinetic results have implied that β-CD/CA/WF graft copolymer could be considered as a promising material for the adsorption of dye from aqueous solutions.     

Effects of intercropping systems of trees with soybean on soil physicochemical properties in juvenile plantations

The intercropping system of tree with soybean in juvenile plantations, as a short-term practice, was applied at Lao Shan Experimental Station in Mao’er Shan Forest of Northeast Forestry University, Harbin, China. The larch (Larix gmelinii)/soybean (Glycine max.) and ash (Fraxinus mandshurica) intercropping systems were studied in the field to assess the effects of the intercropping on soil physicochemical properties. The results showed that soil physical properties were improved after soybean intercropping with larch and ash in one growing season. The soil bulk density in larch/soybean and ash/soybean systems was 1.112 g·cm⁻³ and 1.058 g·cm⁻³, respectively, which was lower than that in the pure larch or ash plantation without intercropping. The total soil porosity also increased after intercropping. The organic matter amount in larch/soybean system was 1.77 times higher than that in the pure larch plantation, and it was 1.09 times higher in ash/soybean system than that in the pure ash plantation. Contents of total nitrogen and hydrolyzable nitrogen in larch/soybean system were 4.2% and 53.0% higher than those in the pure larch stand. Total nitrogen and hydrolyzable nitrogen contents in ash/soybean system were 75.5% and 3.3% higher than those in the pure ash plantation. Total phosphorus content decreased after intercropping, while change of available phosphorus showed an increasing trend. Total potassium and available potassium contents in the larch/soybean system were 0.6% and 17.5% higher than those in the pure larch stand. Total potassium and available potassium contents in the ash/soybean system were 56.4% and 21.8% higher than those in the pure ash plantation. Biography: FAN A-nan (1972–), female, Ph. Doctor in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China.     

Conversion of sulfuric acid lignin generated during bioethanol production from lignocellulosic materials into polyesters with <Emphasis Type="Italic">ɛ</Emphasis>-caprolactone

In this study, polyesters were prepared from sulfuric acid lignin (SAL) that was generated as a by-product during the production of bioethanol from lignocellulosic materials using ɛ-caprolactone (CL). Carboxylic groups were introduced into SAL by a hydrothermal reaction under alkali conditions. The acid form (-COOH) of the obtained polymer (HSAL) was dissolved into ɛ-caprolactone and the mixture was heated at 150°C for 12 h with ZnCl₂ as a catalyst. The structure of the obtained polymer (PCL-HSAL) was proposed based on results of differential scanning calorimetric analysis, swelling tests, and dynamic mechanical thermal analysis. The hydroxyl group in HSAL participated in the ring-opening polymerization of CL. PCL-HSAL with a high HSAL content formed a three-dimensional network that did not dissolve in organic solvents and did not melt at high temperature. PCL-HSAL showed a high swelling property for a suitable ratio of CL to HSAL.     

Comparative Study in Chemical Character and Fatty acid Compositions of Masked Civet''''s Fat and Nutria''''s Oil

IntroductionMaskedciVet(Paguma18vata),Mammalia,Viverridae,ismainlydiStributedinShanxi,Sichuan,Tibet,Yunnanprovinces,etc..Itsmeatisdeliciousandhasspecialflavor.Itiseasytoberaisedartificially,withhighproduCtivity.Nutria(MyocasterCOypus),Rodentia,Capromyidae,originatedinArgentina,Chili,etc.insouthAmerica.Itisakindofherbivoresfur-bearer.itsartificialraisinghassuchmeritsasdurablefurandlowcostandhighproduCtivity.MaskedcivetandnutriahavehigheconomicvalueandwideprospeCtofutilization.Atpresen…