Urea-formaldehyde (UF) resin is one of the most widely used resin adhesive for wood-based panels. The main concern of UF resin bonded wood-based panels is formaldehyde emission and poor water resistance. In this study, activated soybean protein isolate (SPI) was used to modify UF resin for the production of eco-friendly fiberboard panels. The effects of different activated SPI on the properties of UF resins and the resin bonded medium-density fiberboard (MDF) panels were investigated. The free formaldehyde content of the urea-activated SPI modified UF resin was only 0.13 %. Approximately 27.8 % lower than that of the unmodified UF resin. The resin bonded MDF panel with a density of 760 kg/m3 shows a modulus of rupture (MOR) and modulus of elasticity (MOE) of 45.73 MPa and 4005 MPa, which is increased by 25 % and 15 % compared to the unmodified UF resin group. The internal bonding strength (IB) reaches 0.71 MPa, which is about 15 % higher than that of the unmodified UF resin group. The tested 24-hour thickness swelling (24 h TS) of the modified UF resin group is only 8.1 %. The tested formaldehyde content of the sodium dodecyl sulfate (SDS)-activated SPI modified UF resin bonded MDF panel is only 4.8 mg/100 g, which is 20 % lower than that of the control UF resin group. The activated SPI modified UF resin shows great improvement in bonding strength and lower formaldehyde content for MDF panels as compared to the pure UF resin. The chemical groups, crystalline properties, and thermal stability of the pure and the modified UF resins were characterized via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric (TG) analysis. It is confirmed that the activated SPI modified UF resin has similar chemical structure, higher ratio of crystalline regions, and slightly lower thermal stability with compared to the pure UF resin. This study proposes a practical and applicable solution for the utilization of ecofriendly UF resin in wood-based panel production.

智慧教室是借助新兴信息化技术构建的教室新形态,传统课桌椅单一的功能已经无法满足智慧教室空间环境下的教育新需求,课桌椅有必要进行功能升级.智能课桌椅的设计不仅是教室空间设计的一部分,更是技术设计的一部分.本文从利益相关者与课堂设计两个维度系统性分析,得出了智能课桌椅的功能需求体系和两级功能指标.

在现阶段日益激烈的竞争市场、客户需求多样化的环境中,企业板式定制橱柜生产必须面对如何提高产品质量、降低产品成本与缩短生产周期的问题.而生产车间是企业实现价值转化的核心场所,因此生产过程优化对于企业运营效益具有关键意义.本文以A公司某板式定制橱柜柜体车间为研究案例,以精益生产管理中价值流程图为主要研究方法,通过对案例生产现场价值流程图绘制与分析,识别生产管理中的浪费,并提出相应优化措施改善在制品堆积、均衡化生产不足、作业等待等问题.实行改善措施一段时间后,该企业齐套入库率和准时出货率明显提升、不良品率显著降低.

近年来由于中国经济的持续稳定增长,带动了国内酒店行业的飞速发展,越来越多的旅客开始青睐并选择新中式风格酒店,但人们对于酒店整体风格的设计和酒店整体的色彩设计提出了更高的标准.科学合理的色彩搭配能够带给旅客外出居住的舒适感与归属感,让整个酒店客房空间设计更加具有人情化、艺术化的特点,同时也可以塑造酒店品牌独特的色彩符号.本文立足于新中式酒店客房空间的色彩搭配,对酒店设计中需要遵循怎样的色彩搭配原则进行具体分析.

培养具有执着坚守、精益求精、追求完美、敬业守信、推陈出新的"大国工匠"精神的创新实践能力专业人才,是实现制造强国的当务之急.文章以中南林业科技大学林业工程学科为例,指出传统林业工程类专业在大学生创新意识和工程实践能力培养方面存在的问题,通过与企业开展校企"大国工匠"计划训练项目,探索了高等院校与大型企业联合培养人才的新途径.分析了校企"大国工匠"人才培养模式的特点与优势,对如何提高人才培养质量提出了详细措施.通过与3家行业龙头企业开展"大国工匠"人才培养的实践,提高了林业工程类专业大学生对专业的认知程度和热爱程度,培养了大学生的工程实践和创新能力,可满足新工科对人才培养的要求.

在新工科背景下,急需加快培养制造业转型升级的“大国工匠”,培育具有一丝不苟、精益求精“工匠精神”的高技能人才队伍.中南林业科技大学材料科学与工程学院通过总结工科专业人才培养遇到的瓶颈问题,与行业龙头企业一起提出并实施了“大国工匠”人才培养项目.结合学校和企业实际情况,以新工科对人才培养的要求,详细构建了“大国工匠”人才培养方案.发现自“大国工匠”人才培养项目实施以来,学生创新能力和工程实践能力得到显著提升,对专业的热爱度也普遍提高.在此基础上,相继又与多家企业开展了各类人才培养计划项目.

According to the national standard (GB/T 2677.1-GB/T 2677.10), the main components of C. oleifera fruit shell was determined. It explored that pyrolysis characteristics of C. oleifera fruit shell by thermogravimetric analyzer, and comparatively studied the lfame retardancy of C. oleifera fruit shell, Cunninghamia lanceolata, Sp. poplar by cone calorimeter. The results indicated that (1) Benzene alcohol extractive of C. oleifera is twice of peanut shell and 4 times of walnut shell. Hemicellulose of C. oleifera fruit shell is 1.5 times higher than peanut shell and 1.9 times higher than walnut shell. (2)With increasing heating rate, that need higher pyrolysis temperature to reach the same thermal weight loss, so different heating rate have a directly inlfuence on C. oleifera fruit shell’s pyrolysis process. (3) In the combustion process, the mean SEA of Cunninghamia lanceolata and poplar separately is about 2.9 and 8.3 times of C. oleifera fruit shell. It means that C. oleifera fruit shell has ideal smoke suppression effect and is safe to environment because of bringing low smoke production during combustion. All the analysis shows that C. oleifrea fruit shell is an ideal raw material for preparing biomass energy. The future can be carried out in-depth exploration.

使用三点弯曲的方法测试了胶合竹层板不同组坯部位的弯曲弹性模量(MOE),参照胶合木标准AITC-116 2007确定了胶合竹层板的应力分级方法,并对胶合竹层板进行了应力分级.研究结果表明:胶合竹层板的弯曲模量数值均匀,不同位置处的MOE值差异不显著,被测胶合竹层板的MOE值平均为13.5GPa.胶合竹层板的应力等级平均分布在1.9E LAM级和2.0E LAM级.

The rice-straw particle /HDPE composites were made by compression molding process. Effects of the content of the rice-straw particle, the dosage of the titanate coupling agent and the time of hot-press were analyzed. Mechanical properties of the composites were tested, such as MOR, MOE by universal material testing machine. The result showed that rice-straw particle /HDPE composites have relatively good mechanical properties. The effect of the content of the rice-straw particle on the MOR and MOE of rice-straw particle /HDPE composites are very significant. The mechanical properties of the composite material improved by adding titanate coupling agent. The optimized processing conditions are that the content of the rice-straw particle is 50%, the dosage of the titanate coupling agent is 3%, the time of hot-press is 4 min.

This study aimed at exploring a producing method of urea-formaldehyde resin that contained low free formaldehyde. Effects of the pH value of addition stage, the pH value and the temperature of polycondensation stage on the properties of the resin were analyzed. The experimental results showed that controlling the pH value of addition stage to 7.5-8.0, regulating the pH value of polycondensation stage to 4.8-5.1, and keeping the temperature of polycondensation stage to 88-92°C, a low toxic urea-formaldehyde resin adhesive was obtained which contained free formaldehyde 0.08%. Using this resin adhesive, the bonding strength of the plywood reached 1.7MPa, formaldehyde emission of the plywood was 0.7mg/l, reaching the grade E1.

The surface of two kind of crop stalks(corn and sorghum stalk) was modified by cold plasma to improve surface bonding performance of stalks. The effect of cold plasma treatment on stalks' surface wettability was analyzed by using contact angle tester, and the surface topography and chemical composition variation of the treated stalks were studied by SEM-EDAX and FT-IR. The results showed that after treatment by cold plasma, the surface of crop stalks can be etched, and the weak boundary layer can be removed. The crop stalks' surface were covered with a large number of active functional groups, thus the surface bonding performance of the crop stalks can be improved quickly and effectively.

The surface of corn stalk was modified by low temperature plasma to improve corn stalk's surface wettability.The effect of low temperature plasma treatment on corn stalk's surface wettability was analyzed by using contact angle,and the surface topography and compositional variation of the treated corn stalk were studied by employing SEM-EDAX and FTIR technique.The results show that after treated by low temperature plasma,the surface of corn stalk can be sculptured,and the weak boundary layer can be removed,and then the corn stalk's surface were covered with a large number of active functional groups such as hydroxide radical,carbonyl group and carboxyl,thus the wettability of the corn stalk's surface can be improved quickly and effectively.

This study aimed at exploring a producing method of urea-formaldehyde resin adhesive that contained low free formaldehyde.By reducing the molar ratio of formaldehyde to urea,choosing appropriate melamine amount and adding time and adding urea wisely,a low dissociated formaldehyde urea-formaldehyde resin adhesive was synthesized.The experimental results turned out: adjusting the molar ratio of formaldehyde to urea to 1.1,adding 2% of melamine in medium time,using the ratio of urea wisely to 60:15:25,a low toxic urea-formaldehyde resin adhesive was obtained which contained lower than 0.1% dissociated formaldehyde.This adhesive had good properties,low costs and short producing time whose plywood had high bonding strength.

大量苹果木被遗弃,造成资源浪费。为了解决这个问题,采用正交试验对苹果木高密度刨花板制造关键工艺参数进行研究。结果表明:(1)刨花初含水率对刨花板的理化性能不显著;施胶量对刨花板内结合强度、含水率影响显著,而对刨花板静曲强度和2h吸水厚度膨胀率影响不显著;热压时间对刨花板2h吸水厚度膨胀率影响显著,而对其它性能影响不显著。(2)苹果木高密度刨花板较优的工艺参数为:刨花含水率为6%、施胶量为13%、热压时间为300s。

This paper studies the chemical composition of the Malus Mill,the results showed that the ashy substance content 0.32%,cold-water extract content 6.51%,hot-water extract content 7.31%,1% sodium hydroxide ex-tract content 13.69%,benzyl extract content 5.11%,lignin content 24.63%,poly-pen-tose content 24.11%,and cellulose content 44.89%.

In this study, the contact angle among methane diisocyanate(MDl), urea formaldehyde resin(UF) and phenol formaldehyde resin (PF) on surface of sorghum stalk and corn stalk were tested, and the surface free energy of two stalks was reckoned by testing the contact angle of liquid with different surface tensile on each stalk.The result showed that the surface flee energy of two stalks was lower than wood; they were solids of low energy surface.

The effects of 4 factors i.e.,prepressing pressure, moisture content, compression time, and compression number of times,on the maximum compression density and spring back density of wood fiber mat were studied. It was proposed that increasing prepressing times might effectively improve the prepressing effect. The results showed that the maximum compression density and spring back density of fiber mat increased with increasing of prepressing pressure, moisture content, compression time and compression number of times. Prepressing pressure was the main impact factor of maximum compression density, while the moisture content, compressing time and compression number of times are secondary factors. The main factor of spring back density is prepressing pressure, next are compression time and compression number of times. The effect of moisture content was not significant.

By means of SEM-EDAX,the property and element composition of corn stalk surface are studied.The results show that corn stalk surface is relatively smooth and dense.Besides the element H,the surface consists of three elements,i,e.C,O and Si.The Si content of corn stalk surface is about 30% of the total weight.The S and K content of the small swelling scattered on the surface is relative- ly high.

An orthogonal experiment on the reorganizing material of sunflower stalk was done,and the article aralyzed the influence of the glue amount,the hot-press temperature,the pressure and the hot-press time and the technolgical parameter on the product features.Razing the optimum technological parameter and stating the affecting main factors of hot-press quality of the reorganizing material of sunflower stalk.