摘要:This paper describes a method to analyse theoretically velocity ratio of solid togas(vs/va)inside low pressure horizontal-pipe in pneumatic transportation for wood indus-try,and the vs/va of some typical materials are calculated rigorously as well.This resultgives useful reference for engineering application.
关键词:Pneumatic transport;Velocity ratio of solid to gas
摘要:In this paper,structural and mechanical properties of composite plywood withbamboo sheet as face veneer on multi-layer poplar core veneer were investigated.It was alsoanalyzed that relationship between type of board structure,thickness of longitudinal bamboosheets,layer number of poplar core veneer,compression ratio of thickness and mechanicalstrength of the products. Results of the preliminary study showed that both MOR and MOEof the composite plywood were all higher than those of LVL made of poplar,and the MOEwas over that of bamboo plywood.The results indicated that the type of board structure re-markably affected properties of the composite plywood in bending. While thickness of outerlongitudinal bamboo sheets from 3.5mm to 5mm,compression ratio of thickness about 23%,the various mechanical properties were much better.
关键词:Composite plywood with bamboo sheet as face veneer;Poplar;structure;Modu-lus of rupture(MOR);Modulus of elasticity(MOE)
摘要:This study mainly focused on manufacturing technique and accelerated ageingproperties of phenolic resin-bonded flaxboard.Orthogonal design and variance analysis wereused.Through comprehensive analysis,board manufacturing technique and test results ofaccelerated ageing properties of the board were obtained.The results showed:when densityof the board is 0.75g/cm3,board’s properties can meet the German Standard DIN 68763V100 and surplus ratio of this board’s MOR is more than 50%according to ASTM D 1037(6-cycle accelerated ageing standard).
摘要:TG-DTA-T curves of Chinese fir(Cunninghamia lanceolata)untreated and treatedwith flame-retardants were analyzed by the TG-DAT simultaneous method.ResuIts showedthat weight loss of the wood was reduced and char yield increased in charring phase. The TGcurves were further analyzed by thermokinetic method to obtain thermokinetic pararneters ofdifferent phases during wood pyrolysis,and to build a thermokinetic equation. It was foundthat activation energy in drying phase was reduced and the activation energy in both charringphase and calcining phase was different from different flame-retardants used.