蓖麻油聚醚多元醇在聚氨酯软泡中的应用

蓖麻油聚醚多元醇主要是指通过使用双金属催化剂(DMC)制取相对分子质量在2000～5600 的聚氨酯(PU)软泡用多元醇,将该物质与软泡聚醚多元醇H-330 开展性能实验测试。该项结果显示, 相对分子质量为2000 的蓖麻油聚醚多元醇的性能明显好于H-330 聚醚,这项实验证明蓖麻油聚醚多 元醇能够成功代替聚醚多元醇生产普通软泡。本文在这项实验基础上,分析蓖麻油聚醚多元醇在聚 氨酯软泡中的应用研究,为相关领域的研制提供理论支持。     

A Constitutive Relation of Foam Materials

A constitutive model for foam materials is developed based on the Mixture Theories extended by the concept of volume fractions. Within the framework of the axiom of rational thermodynamics, the thermodynamical restrictions on the constitutive relations are investigated and the constitutive equations are formulated for the solid gas two phase foam materials.     

森林泡沫灭火枪的研制

森林泡沫灭火枪是以轻型泵为动力,将森林泡沫剂与水混合后迅速变成泡沫。直接用于灭火的喷泡工具,主要由接口、接头、喷嘴、枪体等部分组成。野外灭火试验表明,该枪灭火效果较好。     

Effects of artificial amendments in potting media on Orthosiphon aristatus growth and development

Artificial polyacrylamide gel (PAG) and urea-formaldehyde resin foam (UFRF) amendments are used for putative enhancement of soil physical properties, including increasing their water holding capacity (WHC). Effects were investigated of these two amendments alone and combined on growth and development of Orthosiphon aristatus (Cats’ Whiskers) grown in either composted pine bark or washed river sand, including under transient water deficit stress. UFRF and PAG were incorporated into these potting media substrates at recommended rates of 30% (v/v) and 0.1% (w/w), respectively. UFRF incorporation reduced bulk density and increased air-filled porosity of composted pine bark from 0.24 g cm⁻³ and 43.3% to 0.18 g cm⁻³ and 50.2%, respectively. UFRF also reduced bulk density of sand from 1.43 g cm⁻³ to 1.17 g cm⁻³ and increased its air-filled porosity from 18.5% to 25.3%. PAG slightly decreased bulk density of composted pine bark to 0.23 g cm⁻³ and also reduced sand bulk density to 1.32 g cm⁻³. Water content of composted pine bark and sand was increased by PAG addition from 47.6% and 27.7% to 51.0% and 34.2%, respectively. However, UFRF and/or PAG did not increase plant available water (PAW) in either composted pine bark or sand. PAW was 23.8% and 14.4%, 23.6% and 15.8%, 22.8% and 14.8%, and 25.2% and 17.8% for composted pine bark and sand controls, these two substrates amended with UFRF, these substrates amended with PAG, and these substrates with UFRF plus PAG, respectively. Neither shoot length nor number was increased by adding UFRF and/or PAG. Similarly, neither shoot fresh nor dry weight was increased by UFRF and/or PAG amendments. UFRF and, moreso, UFRF plus PAG slightly delayed the onset of wilting by 4–15 h in water deficit stressed O. aristatus compared to control and PAG alone in composted pine bark (experiment 1), but PAG did not. However, in experiment 2, UFRF and/or PAG did not delay wilting in either composted pine bark or sand. Thus, when incorporated at suppliers recommended rates, neither UFRF nor PAG conferred appreciable benefits for O. aristatus plant growth in either composted pine bark or sand potting media.     

木材树种对刨花/EPS泡沫复合轻质刨花板性能的影响

为实现刨花板轻量化,通过向芯层引入聚苯乙烯(EPS)泡沫颗粒,制备平均密度为500 kg/m^3的刨花板,探索表芯层刨花构成对板材的剖面密度分布和物理力学性能的影响。结果表明:以杨木细刨花为表层、桉木粗刨花和EPS泡沫颗粒混合物为芯层制备的复合轻质刨花板,其表芯层密度差异最为显著,力学性能达到GB/T 4897-2015《刨花板》中干燥状态下使用的家具型(P2型)刨花板的要求。     

生物质聚氨酯硬质泡沫材料的发泡工艺及结构表征

为了研究沙柳液化产物和异氰酸酯混合发泡制备聚氨酯硬质泡沫材料的最佳发泡工艺,以沙柳液化产物和异氰酸酯为主要原料,纳米有机蒙脱土(OMMT)为形核剂,辛酸亚锡为催化剂,水为发泡剂进行发泡试验。探讨异氰酸酯、OMMT、辛酸亚锡和水的用量对泡沫材料表观密度和压缩强度的影响,并应用X射线衍射、透射电镜、扫描电镜、热重分析等手段对泡沫材料的结构特征进行表征。结果表明:影响发泡试验因素的主次顺序为催化剂、发泡剂、异氰酸酯、成核剂;在优化工艺条件下制得的泡沫材料的表观密度为0.094 g/cm3、压缩强度为0.416 MPa;适量的OMMT能够以插层和剥离态分散在泡沫材料中,显著提高其力学性能、热稳定性和阻燃性能。      

鸡新城疫活疫苗室温保存工艺的初步研究

选用海藻糖、明胶、PVP等成分配制耐热保护剂,采用梯度真空干燥方法,将鸡新城疫病毒(La Sota株)进行泡沫干燥,通过37℃10 d耐老化试验筛选到配方T5的病毒滴度损失为0.2 Lg;NDV-T5泡沫干燥疫苗经DSC测定配方玻璃化转变温度Tg为56.45℃,扫描电镜观察可见较为规则的片状结构;NDV-T5在各温度耐热性能均较好,2℃~8℃保存24个月,25℃保存15个月、37℃保存5个月,病毒含量下降≤1.0 Lg;将不同保存温度的NDV-T5泡沫干燥疫苗免疫1月龄雏鸡,鸡只均能在免疫后14 d产生抗体,与现有商品疫苗效力相当。     

乙酸木质素基聚氨酯硬泡的制备与性能

将乙酸制浆法废液中的木质素进行提取和精制,采用红外光谱(FTIR)、31P-NMR谱和凝胶渗透色谱(GPC)对其结构进行表征,并利用乙酸木质素、聚醚多元醇和甲苯二异氰酸酯在发泡剂和催化剂的条件下合成聚氨酯硬泡。采用TG、DSC和压缩测试对聚氨酯硬泡的热学和力学性能进行研究,并用扫描电子显微镜观察聚氨酯硬泡的泡孔结构。结果表明:乙酸木质素作为多羟基聚合物,可以部分代替聚醚多元醇和异氰酸酯发生反应制备聚氨酯材料;当乙酸木质素添加量为5%时,聚氨酯硬泡的压缩强度达到1.325MPa,比未添加木质素的泡沫高出约63%,此时的压缩模量也达到0.181MPa;随着乙酸木质素添加量增加,乙酸木质素基聚氨酯硬泡的最快分解温度下降,而玻璃化转变温度没有明显升高;乙酸木质素基聚氨酯硬泡泡孔平整均匀。     

发泡水泥对日光温室黏土砖墙保温蓄热性能的改善效果

为改善老旧黏土砖墙的保温蓄热性能,使用发泡水泥对黏土砖墙进行加厚并进行了试验测试。对照温室黏土砖墙由120 mm黏土砖+100 mm聚苯板+240 mm黏土砖（从室内至室外）构成,试验温室结构、管理与对照温室相同,仅北墙采用200 mm 的发泡水泥对原有黏土砖墙进行了加厚（简称为“改造砖墙”）。通过对比分析2温室墙体在典型晴天和阴天内的温度变化,表明：在晴天夜间,黏土砖墙和改造砖墙外表面温度比室外气温分别高(2.8±0.9)和(0.8±0.2)℃,黏土砖墙和改造砖墙内表面温度比室内气温分别高(1.5±0.5)和(2.4±0.2)℃。在阴天,黏土砖墙全天内表面温度全天低于室内气温,而改造砖墙内表面温度在17：30－次日08：00期间较室内气温高(0.3±0.2)℃。因此,采用发泡水泥加厚黏土砖墙不仅可减少墙体热损失,还能增加墙体夜间散热量。     

微波辅助泡沫干燥蓝靛果果粉工艺的研究

选取微波功率、载样量、厚度三个主要影响因素进行单因素试验设计,对影响微波泡沫干燥特性和蓝靛果果粉品质的因素进行分析,把干燥后蓝靛果粉的含水率、花青素和维生素C的含量作为目标因素,对微波泡沫干燥蓝靛果果粉的工艺参数进行正交试验优化.结果表明,载样量是蓝靛果粉品质主要的影响因素,其次是功率和厚度.微波辅助泡沫法干燥蓝靛果的最佳工艺参数为:微波功率7 kW、载样量200 g、料层厚度8 mm