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不同体积采样舱中密度纤维板装载率对VOCs释放的影响 总被引：1，自引：0，他引：1
《林产工业》2021,58(4)
以中密度纤维板(MDF)为试验材料,研究空间大小、MDF人造板装载率对空间挥发性有机化合物(VOCs)释放的影响。试验采用1 m3气候箱、15 L气体采样舱,通过气相色谱质谱联用仪(GC-MS)分析MDF在不同空间装载率下释放的VOCs及其组分化合物。结果表明:随着装载率的增大,2种不同体积采样舱的MDF总挥发性有机化合物(TVOC)释放均呈现上升趋势,但1 m3气候箱内增幅逐渐增大,15 L气体采样舱的增幅则逐渐减小;不同体积采样舱装载率之间线性相关。此外,无论采样舱体积大小,4种装载率(1.0、1.5、2.0 m~2/m~3和2.5 m~2/m~3)条件下,VOCs释放种类中芳香烃、烷烃、醛类和酯类之和总占比均在75%以上。 相似文献
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模拟室内环境释放舱设备的研制与开发 总被引：1，自引：0，他引：1
装饰材料产品释放挥发性有机化合物对室内环境和人体健康会产生重要的影响。使用合理有效的采样技术,准确测得材料释放化合物的释放量对改善室内人居环境、提高产品环保水平具有重要意义。为模拟材料在室内环境下的释放状态,本试验研制一种新型室内环境释放舱,能够模拟材料在室内环境下的释放状态,从而有效测得人造板等装饰材料在不同室内环境条件下挥发性有机化合物的释放量。该释放舱采用空气套恒温方式,有效容积250 L,可调节温度范围为18～40℃,相对湿度范围为40%～70%,空气交换量范围为50～500 L/h,具有偏差、均匀性、波动性绝对值低的特点。环境空气经净化装置处理后,由流量控制器进入流量计,相对湿度调节装置调整相对湿度后进入恒温释放舱,舱内空气循环装置将样品释放有机物与舱内气体混合均匀后经舱空气出口排出,由舱出口管道采样。温度、相对湿度控制器通过温度、湿度传感器对舱内温度、相对湿度进行监测与控制。使用催化燃烧法与高效活性炭过滤结合法对进入释放舱空气净化,保证了释放舱低有机物背景浓度要求,内舱材料表面硅烷化处理方式,提高了C_9之后化合物的回收率。测试试验表明,该环境舱系统背景单体质量浓度≤1.8μg/m~3、TVOC质量浓度≤10μg/m~3,对C_4～C_(14)范围内18种挥发性物质的24 h回收率大于80%。 相似文献
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随着人们环保意识的加强,有机挥发物VOC对环境的危害受到越来越多的重视,文中概述了木材干燥中有机挥发物 VOC的来源、成分、挥发量、挥发浓度及浓度变化过程、影响挥发量和挥发浓度的因素,并介绍了测量和控制木材干燥中VOC挥发的几种方法。旨在加强对木材干燥工业中有害气体研究的重视,为木材干燥的VOC挥发研究提供新思路。 相似文献
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开发探讨了大气中有机污染物气-液采样技术,并以六种多环芳烃(6-PAHs)为有机污染物的代表物对该技术进行了可行性和模拟采样的研究。结果表明该采样技术以二氯甲烷为吸收溶剂,在常见的温度范围内,气体流速在2000～5000 mL/min内,对气态的6-PAHs(苊、芴、菲、芘、苯并(a)芘、苯并(ghj)苝)的回收率达90%±10%。该技术与传统的利用聚氨酯泡沫或XAD类树脂吸附有机污染物气体相比,具有装置结构简单,材料价格低廉,采集过程和样品的后处理步骤简便等特点。 相似文献
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以小兴安岭地区阔叶红松林下主要草本可燃物为研究对象,通过外业调查取样及室内控制环境燃烧试验,测定了42种主要草本可燃物燃烧过程中释放的CO2、CO、CxHy、NO、SO2的气体含量,计算了不同可燃物的排放因子及气体释放量。烟气分析结果表明:CO2、CO、CxHy、NO、SO2等5种气体的排放因子分别为2.930 1、0.459 9、0.013 9、0.008 7和0.022 7;试样燃烧过程中释放的5种气体总量的平均值分别为1 113.46、174.73、5.26、3.29和8.60 mg.g-1。CO2的排放因子和释放量均显著大于其他4种气体。聚类分析结果表明同一科内的草本植物具有相似的排放特性。 相似文献
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为了降低人造板释放挥发性有机化合物(VOC)的检测成本,设计并制作了15L小型环境舱,进行中密度纤维板VOC的主要成分及其释放趋势的检测和考察,并与1m3环境舱检测数据进行对比。结果表明:芳香烃、烷烃和烯烃是中纤板的主要挥发性有机化合物,小型环境舱检测TVOC和芳香烃类的质量浓度值略高于大型环境舱,小型环境舱性能符合要求,可用于人造板释放VOC的检测。 相似文献
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薄板类中密度纤维板动静态弹性模量的检测 总被引：1，自引：0，他引：1
植物挥发物在植食性昆虫的寄主选择和产卵选择中起着重要作用(杜家纬,2001).薄板类中密度纤维板的弹性模量(MOE)是表征其力学性能的主要指标之一.传统都是采用简支静曲测试方法,该方法过程繁琐、消耗时间长(赵仁杰等,2003;Ross et al.,1998).依据振动法测定木质材料的力学性能,过去几十年来已经被证明是一种成功的方法(Moslemi,1967;Ross et al.,1994),测定结果显示振动法测得的力学性质与传统静态弯曲测得的弹性模量间有非常好的一致关系. 相似文献
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柠檬桉木材中二氧化硅的分布和含量的测定 总被引：5，自引：0，他引：5
生物矿化所形成的木材-无机质复合材是当前木材科学研究的热点之一，要实现木材一无机质复合材的人工模拟，其关键还在于研究和探讨木材生物矿化的机理，因此要对木材中无机物的分布及其含量进行研究，从而获取生物矿化所形成的木材一无机质复合材料的形成机理，以此来指导木材的生物改性或木材一无机复合材的仿生合成。本研究采用光学显微镜对柠檬桉木材中二氧化硅的分布进行观察，得出柠檬桉木材中二氧化硅主要分布在射线细胞中，同时大量的晶体存在于轴向薄壁细胞中，早材中的硅石多于晚材中的硅石。采用重量法对木材轴向分布、径向分布中灰分和二氧化硅的含量进行的分析表明：柠檬桉木材中灰分和二氧化硅的含量随着高度的增加而降低，柠檬桉木材灰分和二氧化硅的含量从边材部位向心材部位逐渐减少。 相似文献
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Inthe21stcentury,thewoodsupplyinChinawillcontinLJetobelessthanthedemand,soChinawillneedtousewoodasetfectivelyasPossible.Theuseotwoodcompositesisaveryefficientwaytosavewood.ChinalackssLJfficientforeststomeetitsdemandforwood,especiallyinfinequalitywoods.BecauseofChina'spopulationandfiberdemand,efficientuseofwoocJismoreimportanttoChinathanthattosomeothercoLJntries.However,Chinawasneitherconvincedofthisandnordiditpayattentiontothestudyofwoodcompositesbeforethe1970's.FacingthewoodcrisisChinaf… 相似文献
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To date, the chemical composition and the amount and diversity of volatile organic compounds (VOCs) released by different woody plants samples have been measured and characterized through one of the most common techniques, the gas chromatography–mass spectrometry. However, this technique is very time-consuming and requires sample preparation. By contrast, the Proton-Transfer-Reaction Time-of-Flight Mass spectrometry (PTR-ToF-MS) represents an innovative tool able to provide the whole mass spectra of VOCs with short response time, high mass resolution and without sample preparation. This technique is fast, non-invasive, highly sensitive with a rapid detection system and a very low mass fragmentation of the volatile molecules. The goal of this study was to characterize the VOCs profile of different wood sample cores using a PTR-ToF-MS tool and thereafter to assess whether VOC emissions were specific for some groups of trees. VOCs released from core wood samples belonging to 14 different species were analyzed and subsequently, using an advanced multivariate class-modeling approach, the groups (softwood and hardwood) and the different tree species were discriminated. PTR-ToF-MS was able to detect VOCs from wood and to discriminate between hardwood and softwood and among different species. The great potential and the rapidity of this analysis method allow the PTR-ToF-MS to become a commercial standard tool for monitoring VOCs emitted by wood. 相似文献
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SEBS-g-MAH和原位接枝MAH对木粉/废旧塑料混合物复合材料力学性能的影响研究 总被引：1，自引：0，他引：1
由聚丙烯（PP）、高密度聚乙烯（HDPE）和聚苯乙烯（PS）组成的混合废旧塑料与木粉经高速混合机混合后,采用双螺杆/单螺杆串联挤出机组制备了木粉/混合废旧塑料复合材料。探讨了马来酸酐接枝苯乙烯-乙烯/丁烯-苯乙烯嵌段共聚物（SEBS-g-MAH）和原位接枝马来酸酐（MAH）对木粉/混合废旧塑料复合材料力学性能的影响。结果表明,与使用MAH和DCP的原位反应共混相比,SEBS-g-MAH显著提高了复合材料的抗冲击性能,但对拉伸和弯曲性能的改善不如原位反应共混显著。总的来说,混合废旧塑料制备的复合材料的力学性能要低于纯塑料混合物制备的复合材料,尤其是拉伸断裂伸长率。微观形态研究表明,添加SEBS-g-MAH和原位接枝MAH均可提高木粉与塑料混合物之间的界面相容性,但与添加SEBS-g-MAH相比,原位接枝MAH能更好的改善PP、HDPE、PS与木粉之间的界面结合。原位接枝MAH可被看作是一种改善木粉与塑料混合物间界面相容性的有效途径。此外,采用动态力学分析（DMA）进一步表征了复合材料的储能模量和阻尼因子。 相似文献
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Tadashi Oikawa Toshiya Matsui Yasunori Matsuda Teruko Takayama Hitoshi Niinuma Yasuyo Nishida Kazuo Hoshi Mitsuyoshi Yatagai 《Journal of Wood Science》2006,52(2):140-146
Volatile organic compounds (VOCs) from wood and their effects on artifacts are of intense interest to museum staff who must
strictly manage the preservation environment. In this study, the causal substances of deterioration were inferred by comparison
with laser Raman (LR) spectra of deterioration products. The artifact samples were deteriorated using VOCs from woods (WV
test), and using specific substances that occur in wood VOCs (SV test). The deteriorated samples were analyzed by LR spectroscopy
and the results of the WV and SV tests were compared.
Hinokitiol and acetic acid were found to be two of the main causal substances of deterioration in western red cedar. Deterioration
of iron and copper by spruce did not appear to be caused by acetic acid, as is generally assumed, but by some other unknown
compound(s). Sensitivity to wood-based VOC components depended on the type of artifact. In western red cedar, mitsudasou (litharge) was very sensitive to acetic acid, while other artifacts were sensitive to hinokitiol. The LR method used in this
study is very useful for the inference of causal substances of deterioration based on the detection of small amounts of deteriorated
products such as those generated by deterioration due to wood VOCs.
Part of this article was presented at the 25th Annual Meeting of the Japan Society for the Conservation of Cultural Property,
Kyoto, June 2003 相似文献
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Ulrich Müller Thomas Jost Christian Kurzböck Alexander Stadlmann Wolfgang Wagner Stefan Kirschbichler 《Wood material science & engineering》2020,15(5):312-324
ABSTRACT Multi material mix is a promising approach to reduce weight and the carbon footprint in automotive engineering at competitive costs. As a result, automotive industry is getting more venturous, exploring and applying other materials than metals and plastics – e.g. fibre reinforced plastics (FRPs). In this context, engineered wood products (EWPs) and wood composites should be considered: Wood composites provide high stiffness, strength, excellent damping, high resistance against fatigue and a very low density at low material costs. It is hypothesized that modern wood composites are competitive to metals and artificial fibre-reinforced materials when designed and applied properly. The application of wood and wood composites in automotive engineering calls for precise and reliable material data, required for initial material selection and later in numerical simulation. In this study, a material model normally used for modelling FRPs was adopted. A material database was generated for three hardwood species, to establish the required material parameters and validate material model. Results prove that wooden components can be simulated in crash situations and the selected material model is applicable, even in full vehicle simulation. 相似文献
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Tadashi Oikawa Toshiya Matsui Yasunori Matsuda Teruko Takayama Hitoshi Niinuma Yasuyo Nishida Kazuo Hoshi Mitsuyoshi Yatagai 《Journal of Wood Science》2005,51(4):363-369
Wood is generally used as the interior material in museum storage rooms. Recently, however, the effects of volatile organic compounds (VOCs) from wood on artifacts has become a topic of great concern. The VOCs from four species of wood (western red cedar, spruce, kiri, and sugi) and their effects on artifact materials (two types of metal, seven types of pigment) were investigated using a deterioration-accelerating test, gas chromatography-mass spectrometry, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The results suggested that the influences on artifact materials varied greatly with wood species, and depended on specific components such as hinokitiol or acetic acid rather than the amount of total volatile organic compounds (TVOCs). It is a very serious problem that of the four species of wood, western red cedar (rich in hinokitiol), which has been recommended as an interior material for museum storage rooms, showed the heaviest deterioration on metal samples, and only this type of wood discolored enpaku (white lead) and rokushou (malachite, verdigris). In such storage rooms, museum artifacts should be carefully monitored. When selecting an interior material for a storage room or studying methods of preventing deterioration, it is very important to consider fully the characteristics of wood VOCs, not only the amount of TVOC.Part of this paper was presented at the 24th (Tokyo, June 2002) and 25th (Kyoto, June 2003) Annual Meeting of the Japan Society for the Conservation of Cultural Property 相似文献
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