高固分涂料开发前景亮丽

大气中有机挥发物（以下简称VOC）在日光的作用下生产的O3在较低浓度下就会对人体健康产生非常不利的影响，而涂料工业产生的VOC量     

尾叶桉干燥过程中有机挥发物释放的研究

采用小型干燥机干燥木材,采用高效液相色谱仪和气相色谱仪对干燥过程中释放的有机挥发物进行分析。结果表明,尾叶桉干燥释放的主要物质是甲醇、乙酸,其次是甲酸、乙醛、甲醛、丙烯醛/丙酮,而萜烯类挥发物很少。尾叶桉高温干燥释放的挥发物比常规干燥明显增多,尾气中甲醇浓度超过标准限值。甲醛高温干燥时随含水率降低释放速率增大,其它物质在高温和常规干燥时的释放速率随含水率减少呈下降趋势。     

杉木干燥过程中的有机挥发物释放

采用小型干燥机干燥木材,在冰浴中用酸化的2,4-二硝基苯肼溶液和去离子水分别对尾气中醛类和有机酸、醇类采样,用活性炭管对萜烯类采样,采用高效液相色谱仪和气相色谱仪对有机挥发物进行分析.结果表明:杉木干燥释放的主要物质是甲醇、乙酸和甲酸,其次是乙醛、甲醛、丙烯醛/丙酮;萜烯类挥发物主要有α-蒎烯、D-柠檬烯、莰烯、β-蒎烯、β-水芹烯.杉木高温干燥释放的醛类和酸、醇类挥发物远高于常规干燥,高温和常规干燥中挥发物总量分别为91.7 g·m-3和29.9 g·m-3,但萜烯类挥发物总量差异很小.木材干燥终含水率对醛类和有机酸、醇类释放量影响较大,对萜烯类释放量影响较小.甲醛高温干燥时随含水率降低释放速率增大,其他物质在高温和常规干燥时的释放速率随含水率减少呈下降趋势.     

松材室干过程中VOCs释放规律研究

木材干燥排放的尾气因含有对环境有害的VOCs而备受关注。以企业实际运行的木材干燥过程为研究对象,采样研究了松材在室干过程中VOCs的释放规律,包括VOCs采样方式、采样时间以及采样点对VOCs释放的影响。结果表明:松材在室干过程中释放醛类及萜烯类等化合物25种,其中甲醛与乙醛浓度高于国标规定的污染物排放浓度限值,苯与丙烯醛浓度低于排放限值;采样40 min测得的VOCs释放量高于采样20 min;不同采样点的VOCs释放量有差别;采样方式对VOCs释放无明显影响。总有机挥发物释放量呈先升高,后降低,再升高的趋势,在含水率为30%左右达到最大。     

杨木热解过程中的有机挥发物释放

研究了杨木[populus tremula]在120～300℃温度范围内热解过程中释放的VOC成分与含量,采用热重红外联用仪分析了杨木的失重和热解速度,以及热解产物的官能团,在此基础上用热解气质联用仪对杨木热解过程中释放的VOC进行分析。结果表明:杨木在热解过程中释放的VOC主要为酚类,其次是酮类、酸类、醇类、醛类。该研究旨在为木材热改性过程中有机挥发物控制处理技术和排放标准提供理论基础。     

欧美日木制品有机挥发物监管制度研究

随着人们保护人类健康和环保意识的增强,国内外纷纷出台各种监管措施,对木制品中有机挥发物(VOC)的释放限量提出严格要求。笔者研究了欧、美、日对木制品V0C的监管制度,为我国木制品进一步加强安全管理提供借鉴和参考。     

4种木材常温下醛和萜烯挥发物的释放

利用高效液相色谱仪和气相色谱仪分析4种木材(杉木、杨木、马尾松和尾叶桉)中有机挥发物的成分及含量,结果表明:4种木材生材常温均可释放多种醛和萜烯挥发物,其中乙醛的释放量最高;杉木和杨木释放的醛类明显高于马尾松和尾叶桉;杉木释放的萜烯类明显高于其他3种木材;温度由20 ℃上升到40 ℃,杉木醛类和萜烯类释放量显著增加.     

家具用水性封闭底漆在低温干燥过程中水分挥发规律的研究

在实验室条件下,对家具用水性封闭底漆在低温干燥过程中的水分挥发规律进行了研究。结果表明,在干燥环境相同的条件下,枫木贴面涂饰板和玻璃涂饰板涂层的水分挥发规律有一定的相似性。但是,枫木贴面涂饰板涂层的水分一部分渗透到木材中,一部分向空气中挥发,而玻璃涂饰板只向空气中挥发;枫木贴面涂饰板涂层水分挥发量小于玻璃板,涂层内水分残留量大于玻璃涂饰板。     

两种干燥环境下思茅松干燥前后抽提物变化的初步研究

采用传统的化学分析和高效液相色谱分析方法,研究思茅松木材干燥前后抽提物成分的变化情况.结果表明:思茅松木材经高温干燥,不仅会发生水分扩散等物理变化,还会发生裂解等化学变化.认为这是由于可挥发性化合物在干燥过程中随水分的蒸发和迁移而从木材中挥发出来,此外,干燥温度升高使木材提取物中部分成分由不可裂解物质变成了可裂解物质,并且从未材中挥发出来.     

对我国木材干燥技术创新与发展问题的几点思考

概述了我国木材干燥工业发展的现状.指出了目前木材干燥工业发展中存在的主要问题,如总体水平较低,干燥技术发展不均衡,木材干燥学科在行业内的地位和影响力有所下降.提出了应加强理论创新;针对我国木材资源特点重视木材干燥新技术的研究与技术的集成创新;倡导"节能减排"的绿色干燥;充分发挥学会、协会的引领作用等推动木材干燥工业健康发展的思路.     

Review on Volatile Organic Compounds Emission from Wood Composites

INTRODUCTIONWhen people think about air pollution, they usually thinkabout smog, acid rain, CFC's, and other forms ofoutdoor air pollution. But do you know that air pollutioncan also exist inside homes and other buildings? It can,and every year, the health of many people is affectedby chemical substances present in the air withinbuildings. In fact, the indoor air pollution is more seriousthan outdoors’ actually. In recent years, someresearches have proven that the degree of indoor airpo…     

不同容积环境舱检测人造板TVOC释放的对比

以中密度纤维板和聚氯乙烯贴面中密度纤维板为研究对象,采用便携式手持VOC检测仪分别检测0.015 m3小环境舱和1 m3大环境舱中两种板材总挥发性有机化合物（TVOC）释放速率,并进行对比分析其相关性.实验结果表明：板材在大、小环境舱中TVOC释放速率衰减趋势相同,说明舱体内气体混合的均匀性不会受到舱体容积的影响;大、小环境舱检测数据相关性很好,但是存在偏差,相对偏差在10％左右,小环境舱检测结果略高于大环境舱.     

小型环境舱法检测中纤板挥发性有机化合物的研究

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。     

应用气候箱法测定胶合板的VOC释放

采用气候箱模拟室内气候环境,研究胶合板的甲醛释放规律,分析环境因素对处于稳定释放期的胶合板甲醛及其他VOC释放机理的影响.研究发现:在模拟的空气环境条件下,胶合板甲醛释放呈现的规律为:在较短时间内急速上升,达到最大值后逐渐衰减,直到趋于稳定值;在稳定释放状态,环境因素对甲醛及某些VOC散发有显著作用.同时对VOC作了化学成分的检测,受试胶合板主要释放有8种VOC.     

环境温度对室内装修有害气体释放影响的研究

以东北地区两种代表性的品牌刨花板为研究对象,分析温度对挥发性有害气体（VOCs）释放量的影响。利用小型气候箱和手提式VOCs测试仪分别测量两种刨花板在15℃、23℃、25℃和35℃情况下的VOCs释放量。研究表明：温度为23℃时,板1VOCs的最初释放量高于板2;温度为35℃时,刨花板中VOCs释放量要高于其他温度情况下的释放量。由此可以看出环境温度对刨花板VOCs的释放量有明显的影响,即随着温度的升高板材有害气体的释放量增加。     

氮添加对马尾松和木荷幼苗根系土壤挥发性有机化合物的影响

为了解土壤挥发性有机化合物(VOCs)对氮沉降的响应,本研究以马尾松和木荷幼苗为研究对象,设置3个氮水平(5.6、15.6和20.6 g·m^-2·a^-1)和两种氮添加方式(土壤施氮和叶面施氮),通过质子转移反应飞行时间质谱仪分析植物土壤VOCs对不同氮水平和氮添加方式的响应。结果表明,马尾松和木荷幼苗根系土壤释放的总VOCs通量为19.50~70.94 pmol·g^-1·h^-1,以含氧VOCs(乙醛、甲醇和乙烯酮)和含氮VOCs(甲酰胺和丙胺)为主,分别占总VOCs的22.04%~47.71%和3.31%~38.68%。两种氮添加方式均显著地促进马尾松和木荷幼苗根系土壤含氮VOCs释放,这与土壤铵态氮和硝态氮含量显著相关。叶面施氮处理下马尾松根系土壤总VOCs释放显著增加,不同幼苗根系土壤释放的不同种类VOCs对氮水平和氮添加方式的响应不一致。研究结果可为评估土壤VOCs对大气氮沉降增加的响应提供基础数据。     

Emissions of volatile organic compounds from heated needles and twigs of <Emphasis Type="Italic">Pinus pumila</Emphasis>

A study was conducted to explore the mechanism that emissions of volatile organic compounds(VOC) from heated needles and twigs(200°C,within 15 min) of Pinus pumila affect fire behaviours using the technology of Thermal Desorption-Gas Chromatography-Mass Spectrometry(TD-GC-MS).The results indicated that the main components of VOC from heated needles and twigs are terpenoids.Most of these terpenoids are monoterpenes.Terpenoids account for 72.93% for the needles and 92.40% for the twigs of the total VOC,and their emission ratios are 61.200 μg·g-1 and 217.060 μg·g-1 respectively.Heated twigs can emit more terpenoids than heated needles because twigs had more volatile oils than needles.In actual fires,these large amounts of terpenoid emissions,especially the monoterpene emissions,have strong effects on fire behaviors that are not only in the initial stage but also in the fast propagation stage of fires.These flammable gases are capable of causing violent combustion and creating crown fires.In addition,if these gases accumulate in an uneven geographical area,there will be a possible for eruptive fires and/or fires flashover to occur.     

Volatile organic compounds (VOC) as biomarkers for detection of Ceratocystis platani

Ceratocystis platani causes canker stain of plane trees, and it represents a serious disease of Platanus spp. both in the United States and Europe. Current chemical or biological controls do not effectively manage C. platani, so new preventive methods need to be developed in order to limit this pathogen spreading. In this work, we have characterized the main volatile organic compounds (VOC) emitted in vitro from pure cultures of C. platani and other common pathogenic fungal species of hosts plants growing in the same ecosystems as plane trees. We found that C. platani emitted a similar blend of VOC compared with phylogenetically similar species C. populicola. In particular, C. platani was characterized by emission of isoamyl acetate and isobutyl acetate while C. populicola by ethyl acetate and isobutyl acetate, which were not released by any of the other out‐group fungal species grown on the same medium. Moreover, following a targeted approach based on the main VOC found in vitro, we have successfully validated in vivo that VOC uniquely emitted by C. platani (i.e. isobutyl acetate along with isoamyl alcohol) were released from the bark of plane trees following C. platani inoculation. Our results highlight the possibility to exploit VOC emitted specifically by C. platani as biomarkers to recognize Platanus x acerifolia plants infected by this pathogen.     

氧冷等离子体处理对杨木胶合板甲醛释放量的影响

随着近年来家庭装饰装修要求的提高,越来越多的人造板开始进入室内环境。如何降低人造板的甲醛释放量已成为木材工业界的一个热点研究课题。笔者利用氧冷等离子体技术对杨木单板进行改性处理,并制成三层胶合板,研究氧冷等离子体处理对杨木胶合板甲醛释放量的影响。研究结果表明:采用氧冷等离子体处理的方法降低杨木胶合板甲醛释放量是可行的,产品甲醛释放量下降率可达5.66%～23.90%;随着氧冷等离子体处理时问的延长,胶合板甲醛释放量下降率呈先升后降趋势,随处理功率的增大也呈先升后降趋势。     

Volatile organic compound emission from holm oak infested by gypsy moth larvae: evidence for distinct responses in damaged and undamaged leaves

Foliage of Quercus ilex L. (holm oak), a widespread Mediterranean species, constitutively emits large quantities of a complex genotype-dependent mixture of volatile organic compounds (VOCs). During a mass outbreak of gypsy moth (Lymantria dispar L.) in southern France, we examined the effects of gypsy moth feeding on VOC production from whole apices and single leaves of Q. ilex. Feeding induced the emission of new VOCs at rates up to 240 ng m(-2) s(-1) (16% of the total VOC release), which mainly consisted of sesquiterpenes, a homoterpene and a monoterpene alcohol. The new compounds were emitted after a delay of several hours following infestation and their production declined rapidly when caterpillars were removed. Undamaged leaves of infested trees emitted new VOCs, but with a different composition to those of damaged leaves and at lower rates. Neither caterpillars nor caterpillar excrement released VOCs. Emission of constitutive VOCs by undamaged leaves of infested trees temporary increased by up to 30%, whereas, in damaged leaves, they remained stable and decreased after some days when necrotic spots occurred around the feeding sites. In continuous light and at constant temperature, emissions of new VOCs showed a marked diurnal cycle, whereas those of constitutive VOCs did not. The results suggest that induced VOCs make a significant contribution to the atmospheric VOC load and may mediate trophic interactions. The observed differential local and systemic responses in composition, quantity and time courses of emissions mirror the existence of several regulation processes triggered by different signaling compounds and elicitors.