苏联的低质材削片技术

1.前言将低质木材削成工艺木片或燃料木片,是开发利用低质材的良好途径之一。但是,在削片生产中劳动量、动力消耗以及木材损失较大,因而经济效益不高。苏联的统计表明,削片生产中的原料准备消耗的劳动量占总耗量的40～60%,在原料准备过程中所使用的各种机械设备所需功率为56～60KW,有的高达114～136KW,平均生产率为40～70m^3/

实木家具用低质材提质加工技术通过验收

由中国林科院木材工业研究所主持承担的,林业公益性行业科研专项重大项目“实木家具用低质材提质加工技术研究与示范”2017年10月,通过了国家林业局科技司组织的验收.该项目于2014年启动,由中国林科院木材所、北京林业大学、南京林业大学以及宜华生活科技股份有限公司、徐州中原木业有限公司共同完成.

“实木家具用低质材提质加工技术研究与示范”项目进展顺利

2015年12月，国家林业公益性行业科研专项重点项目“实木家具用低质材提质加工技术研究与示范（201404501）”年度总结会，在广东省宜华木业股份有限公司宜华木业研究院召开。

“实木家具用低质材提质加工技术研究与示范”项目启动

2014年5月，国家林业公益性行业科研专项重大项目“实木家具用低质材提质加工技术研究与示范”项目在京启动。

国家林业公益性行业科研专项重大项目——“实木家具用低质材提质加工技术研究与示范”项目启动

5月17日,＂实木家具用低质材提质加工技术研究与示范＂项目在北京正式启动。其中,人工林杨木压缩增强加工技术、人工林杨木浸渍增强加工技术、改性材专用无醛胶黏剂制备与胶接技术、改性杨木饰面技术以及实木家具设计与制造技术,是实木家具用低质材提质加工技术研究与示范项目需要突破的关键,进而实现人工林低质材代替优质珍贵木材用于实木家具制造。

用低质材制备异型木制品方法的研究

本文研究了以低质木材为原料 ,采用热模压法来制备异型木制品的原理和工艺。

创生新型木质基复合材料实现低质材的高值利用

我国森林资源总量不足,人均森林蓄积只有世界人均占有量的1/7,人均木材消耗量只占世界人均的1/3。因此科学合理地加工和利用现有的木材资源极为重要。提高木材的耐久性、延长使用寿命、改良木材品质、提高利用价值,这是国内外研究者十分关注的主题。其中,创生新型木质基复合材料是实现低质材及其废弃物高效利用的有效途径之一。

云星木业:立志掀起木材工业革命

“单板层积材”是由单板顺纹组环胶合而成的一种新型人造板材,它不仅保留了实木纹理美观、加工性能良好的优点,而且还具有许多天然实木所不具备的优良特性,例如良好的尺寸稳定性和较高的强度等等。它是替代天然实木的新型结构用材,其预制性和性能的可控制性远远优于其它材料,可以广泛用于建筑、家具、车船制造等行业。

A Model for Mechanical Property Evaluation of the Periodic Porous Low-k Materials by SAW

The influence of the distribution of nano-pores on the mechanical properties evaluation of porous low-k films by surface acoustic waves （SAW） is studied. A theoretical SAW propagation model is set up to characterize the periodic porous dielectrics by transversely isotropic symmetry. The theoretical deductions of SAW propagating in the low-k film/Si substrate layered structure are given in detail. The dispersive characteristics of SAW in differ- ent propagation directions and the effects of the Young＇s moduli E, E′ and shear modulus G′ of the films on these dispersive curves are found. Computational results show that E′ and G′ cannot be measured along the propagation direction that is perpendicular to the nano-pores＇ direction.

Hydration mechanism of low quality fly ash in cement-based materials

The hydration mechanism of low quality fly ash in cement-based materials was investigated. The hydration heat of the composite cementitious materials was determined by isothermal calorimetry, and the hydration products, quantity, pore structure and morphology were measured by X-ray diffraction(XRD), thermalgravity-differential thermal analysis(TG-DTA), mercury intrusion porosimetry(MIP) and scanning electron microscopy(SEM), respectively. The results indicate that grinding could not only improve the physical properties of the low quality fly ash on particle effect, but also improve hydration properties of the cementitious system from various aspects compared with raw low quality fly ash(RLFA). At the early stage of hydration, the low quanlity fly ash acts as almost inert material; but then at the later stage, high chemical activity, especially for ground low quality fly ash(GLFA), could be observed. It can accelerate the formation of hydration products containing more chemical bonded water, resulting in higher degree of cement hydration, thus denser microstructure and more reasonable pore size distribution, but the hydration heat in total is reduced. It can also delay the induction period, but the accelerating period is shortened and there is little influence on the second exothermic peak.

Tape casting of borosilicate glass/Al_2O_3 composites for LTCC substrate with various relative molecular masses of PVB

The dispersion, stabilization and rheological properties of the slurry with various relative molecular masses of PVB were studied. The sintering properties, microstructure and dielectric properties of borosilicate glass/Al203 composites were also investigated. The intensities of the typical vibrating bands decrease with the decrease of the relative molecular mass of PVB, which demonstrates that the content of butyral groups in PVB binders decreases correspondingly, leading to a rapid decrease in the viscosity of the mixed slurry. The solid content of samples increases with the decrease of the relative molecular mass of PVB, and this further leads to the increase of tape thickness, bulk density and dried-shrinkage coefficient of tapes. The bulk density, relative density, three-point strength and dielectric constant of sintered samples increase with the increase of the solid content, and the shrinkage and dielectric loss decrease. By contrast, samples for PVB-5s exhibit better properties of a bulk density of 3.10 g/cm3, a relative density of 98.1%, a three-point strength of 208 MPa, aεt value of 8.01, a tanδ value of 7.6× 10^-4 at 10 MHz and a well matching with Ag electrodes.

Identification of vibrational mode symmetry and phonon anharmonicity in SbCrSe_(3)single crystal using Raman spectroscopy

Developing an understanding of the physics underlying vibrational phonon modes,which are strongly related to thermal transport,has attracted significant research interest.Herein,we report the successful synthesis of bulk SbCrSe_(3)single crystal and its thermal transport property over the temperature range from 2 to 300 K.Using angle-resolved polarized Raman spectroscopy(ARPRS)and group theory calculation,the vibrational symmetry of each observed Raman mode in the cleaved(001)crystal plane of SbCrSe_(3)is identified for the first time,and then further verified through firstprinciples calculations.The ARPRS results of some Raman modes(e.g.,Ag2~64 cm-1 and Ag 7~185 cm-1)can be adopted to determine the crystalline orientation.More importantly,the temperature dependence of the lattice thermal conductivity(κL)is revealed to be more accurately depicted by the three-phonon scattering processes throughout the measured temperature range,substantiated by in-situ Raman spectroscopy analysis and the model-predictedκL.These results reveal the fundamental physics of thermal transport for SbCrSe_(3)from a completely new perspective and should thus ignite research interest in the thermal properties of other lowdimensional materials using the same strategy.