松木/UPR复合材料性能的研究

以红松、樟子松粉末和纤维为增韧剂,分别加入到不饱和聚酯树脂(UPR)中,制备了松木粉(纤维)/UPR复合材料。研究了各种增韧剂对该复合材料力学性能的影响。结果表明:松木粉和松木纤维提高了UPR复合材料的韧性。其中,红松粉/UPR复合材料的冲击强度为1.81 kJ/m2,拉伸强度为10.402 MPa;红松纤维/UPR复合材料的冲击强度为2.01 kJ/m2,拉伸强度为10.950 MPa;樟子松粉/UPR复合材料的冲击强度为1.93 kJ/m2,拉伸强度为11.220 MPa;樟子松纤维/UPR复合材料的冲击强度为2.30 kJ/m2,拉伸强度为11.372 MPa。另外,当红松和樟子松纤维用量分别为20%和30%时,对UPR复合材料的增韧效果最佳。     

Allelopathic effects ofPinus densiflora on undergrowth of red pine forest

Correlation between the distributional frequency of undergrowth species of red pine forest and their germination and growth effected by pine extracts and leachates was found. It was made clear by germination and growth tests that pine toxic substances inhibit the germination and growth of low frequency species more than high frequency species in a red pine forest and that these substances are contained in descending concentration in fresh and fallen leaves, roots, pine forest soil, and pine rain. The concentration of pine toxic substances in extracts or leachates was affected by extracting or leaching within a given period of time, requiring a few hours for extracts or a few days for leachates. The amount of dry weight inhibition of the undergrowth treated by pine leachates was expressed as a growth inhibition index (GII) for the comparison of tolerance in various species. GII is a relative value (%) of the test groups against the control and it is an exponential function of the amount of pine toxic substances affecting the dry weight of the undergrowth. The substances were analyzed by paper and gas chromatography. Benzoic acid and 11 phenolic acids were identifed by gas chromatography. Benzoic acid was considered to be a key factor of allelopathy in the red pine forest.     

Volatile Profile Differences and the Associated Sirex noctilio Activity in Two Host Tree Species in the Northeastern United States

Sirex noctilio females are known to be attracted to stem sections of stressed pine trees for oviposition. The volatile profiles and attractiveness of Eastern white pine (Pinus strobus) and two chemotypes of Scots pine (P. sylvestris) were compared after stem injection with herbicide. In general, trap captures on herbicide-treated trees were higher than on controls. The high-carene chemotype of Scots pine captured the highest numbers of females, followed by the low-carene chemotype, and finally the Eastern white pine. Herbicide-treated trees of both species emitted larger quantities of volatiles than the controls. The herbicide treatment induced higher volatile emission rates in the Scots pine chemotypes than in white pine, although there was no difference between the two chemotypes. However, qualitative differences were found between the volatile profiles of the two species as well as between the two Scots pine chemotypes, which could account for the differential attractiveness of the species and chemotypes tested.     

Monoterpene Emissions from Lodgepole and Jack Pine Bark Inoculated with Mountain Pine Beetle‐Associated Fungi

Abstract

Relative monoterpene levels were analyzed from bark samples of lodgepole pine, jack pine, and their hybrids inoculated with mountain pine beetle (MPB)–associated fungi (Leptographium longiclavatum, Grosmannia clavigera, and Ophiostoma montium). Lodgepole pine showed the largest changes in relative emissions as a result of fungal inoculation. The relative emission of β‐phellandrene increased with fungal inoculation, making it the most abundant monoterpene for inoculated samples. Relative emissions of limonene and α‐pinene decreased in inoculated lodgepole pine. Lodgepole (5.6) and jack (146) pine differed in the ratio of α‐pinene to myrcene; two monoterpenes involved in pheromone synthesis by the MPB. These differences may contribute to the attractiveness of the two species as hosts for MPB; with jack pine potentially less attractive than lodgepole pine. Fungal inoculation reduced α‐pinene:myrcene ratios in lodgepole pine, which suggests one possible mechanism by which the fungi benefit the beetle.     

Effect of Water Stress and Fungal Inoculation on Monoterpene Emission from an Historical and a New Pine Host of the Mountain Pine Beetle

The mountain pine beetle (Dendroctonus ponderosae, MPB) has killed millions of lodgepole pine (Pinus contorta) trees in Western Canada, and recent range expansion has resulted in attack of jack pine (Pinus banksiana) in Alberta. Establishment of MPB in the Boreal forest will require use of jack pine under a suite of environmental conditions different from those it typically encounters in its native range. Lodgepole and jack pine seedlings were grown under controlled environment conditions and subjected to either water deficit or well watered conditions and inoculated with Grosmannia clavigera, a MPB fungal associate. Soil water content, photosynthesis, stomatal conductance, and emission of volatile organic compounds (VOCs) were monitored over the duration of the six-week study. Monoterpene content of bark and needle tissue was measured at the end of the experiment. β-Phellandrene, the major monoterpene in lodgepole pine, was almost completely lacking in the volatile emission profile of jack pine. The major compound in jack pine was α-pinene. The emission of both compounds was positively correlated with stomatal conductance. 3-Carene was emitted at a high concentration from jack pine seedlings, which is in contrast to monoterpene profiles of jack pine from more southern and eastern parts of its range. Fungal inoculation caused a significant increase in total monoterpene emission in water deficit lodgepole pine seedlings right after its application. By 4 weeks into the experiment, water deficit seedlings of both species released significantly lower levels of total monoterpenes than well watered seedlings. Needle tissue contained lower total monoterpene content than bark. Generally, monoterpene tissue content increased over time independent from any treatment. The results suggest that monoterpenes that play a role in pine-MPB interactions differ between lodgepole and jack pine, and also that they are affected by water availability.     

The Lodgepole × Jack Pine Hybrid Zone in Alberta, Canada: A Stepping Stone for the Mountain Pine Beetle on its Journey East Across the Boreal Forest?

Historical data show that outbreaks of the tree killing mountain pine beetle are often preceded by periods of drought. Global climate change impacts drought frequency and severity and is implicated in the range expansion of the mountain pine beetle into formerly unsuitable habitats. Its expanded range has recently reached the lodgepole × jack pine hybrid zone in central Alberta, Canada, which could act as a transition from its historical lodgepole pine host to a jack pine host present in the boreal forest. This field study tested the effects of water limitation on chemical defenses of mature trees against mountain pine beetle-associated microorganisms and on beetle brood success in lodgepole × jack pine hybrid trees. Tree chemical defenses as measured by monoterpene emission from tree boles and monoterpene concentration in needles were greater in trees that experienced water deficit compared to well-watered trees. Myrcene was identified as specific defensive compound, since it significantly increased upon inoculation with dead mountain pine beetles. Beetles reared in bolts from trees that experienced water deficit emerged with a higher fat content, demonstrating for the first time experimentally that drought conditions benefit mountain pine beetles. Further, our study demonstrated that volatile chemical emission from tree boles and phloem chemistry place the hybrid tree chemotype in-between lodgepole pine and jack pine, which might facilitate the host shift from lodgepole pine to jack pine.     

思茅松松节油标准样品的定值研究

研究了作为云南省主要采脂树种的思茅松松节油标准样品的制备和稳定性、均匀性及其定值方法。思茅松松节油制备采用水蒸气蒸馏法,含量分析采用气相色谱面积归一化法。制备得到的松节油标准样品在36个月内保持稳定,通过了均匀性检验。多实验室联合定值结果为:α-蒎烯含量X_标=75.30 %,标准不确定度U_A=0.23 %,扩展不确定度U_0.95=0.45 %; β-蒎烯含量X_标=17.80 %,标准不确定度U_A=0.08 %,扩展不确定度U_0.95=0.16 %; β-水芹烯含量为X_标=3.50 %,标准不确定度U_A=0.08 %,扩展不确定度U_0.95=0.16 %。     

Accelerated weathering performance of Scots pine preimpregnated with copper‐based chemicals before varnish coating Part:1 coated with cellulosic and polyurethane varnishes

This study aimed to determine the effect of accelerated weathering on gloss, surface hardness and colour changes of Scots pine (Pinus sylvestris L.). Test samples were impregnated with Adolit KD‐5, Wolmanit CX‐8 and Celcure AC‐500 covered with cellulosic and polyurethane varnishes. The results showed that the values of surface hardness and gloss increased after accelerated weathering. While the surface hardness of Scots pine was increased for impregnated and polyurethane‐coated varnish, it decreased for impregnated and cellulosic varnish‐coated Scots pine after 1000 hours of accelerated weathering exposure. Copper‐based chemical impregnation and varnish coating developed the gloss of Scots pine specimens relative to the surface characteristics observed in single‐coated Scots pine specimens. While the most appropriate chemical was Celcure AC‐500 for surface hardness, it was Adolit KD‐5 for the gloss of Scots pine after 1000 hours of accelerated weathering exposure. Wood specimens impregnated prior to the application of varnish were more effective in stabilising the colour of Scots pine than Scots pine only coated with varnish. Polyurethane varnish‐treated Scots pine showed better colour stability for each partial and total accelerated weathering exposure period. The total colour changes were lowest for polyurethane varnish‐coated Scots pine impregnated with Celcure AC‐500 after 1000 hours of accelerated weathering exposure.     

水性木器涂料在松木涂装中的应用

介绍了常用松木的特点、种类,水性木器涂料在松木涂装中的涂装类型及特点。并简述了用水性木器涂料进行松木涂装时的优缺点,以及松木的除油脂及施工水性封闭底漆的重要性。     

Effect of experience with pine (Pituophis melanoleucus) and king (Lampropeltis getulus) snake odors on Y-maze behavior of pine snake hatchlings

The abilities of hatchling pine snakes (Pituophis melanoleucus) and king snakes (Lampropeltis getulus) to discriminate the chemical trails of pine and king snakes was investigated inY-maze experiments. Pine snakes were housed for 17 days either with shavings impregnated with pine snake odor, king snake odor, or no odor to test for the effect of experience on choice. Both pine and king snake hatchlings entered the arm with the pine snake odor and did not enter the arm with the king snake odor. The data support the hypothesis that hatchlings of both species can distinguish conspecific odors from other odors and that our manipulation of previous experience was without effect for pine snake hatchlings.     

松节油标准样品的制备及特征组分研究

对比研究了溶剂法和水蒸气蒸馏法制备马尾松、湿地松和思茅松松节油的工艺,使用水蒸气蒸馏法制得的3种松节油样品均符合国家标准《脂松节油》GB/T 12901-2006的质量指标要求。GC和GC-MS分析结果显示, 3种松节油样品的主要特征组分有α-蒎烯、β-蒎烯、苧烯、β-水芹烯和长叶烯、石竹烯等,而且含量差异比较明显。主要成分α-蒎烯与β-蒎烯相对含量之比分别为马尾松松节油8.5、湿地松松节油2.0和思茅松松节油4.0,该比值具有非常明显的差异性,其比值的大小有可能作为松树树种鉴别的一项重要判断依据。     

松木屑生物质热解特性研究

以氮气为载气,采用热重分析仪对松木屑进行热解实验,考察了载气流速、升温速率等对松木屑热解过程的影响,求解了热解表观动力学参数。研究表明,松木屑的热解过程分三个阶段,主要热解温度为200～450℃,600℃后热解反应基本完成;载气流速对热解反应影响较小,升温速率对热解反应影响较大;松木屑热解表观活化能在40～70 kJ/mol范围内。     

Thermal Behavior of Deteriorated Wood Waste

Abstract

This paper investigates the thermal behavior of woody biomass waste—demolition wood of Japanese cedar (Cryptomeria japonica) and insect-attacked forest residue of Japanese red pine (Pinus densiflora)—using proximate analyses, thermogravimetry (TG), and differential thermal analysis (DTA), with comparison to virgin wood. For the pine samples, there was no significant difference in thermal behavior or elemental composition between the virgin pine and pine that had been damaged by insects, indicating that insect-damaged pine received here can be treated as virgin pine in terms of energy utilization. The cedar demolition wood used here was partly degraded by termites or fungi. Its degraded part had a lower weight loss rate under nitrogen and a broader exothermic peak in the char combustion stage under air than cedar virgin wood. The changes in the relative levels of the chemical components and the resultant chemical changes that occur upon fungal degradation might complicate char formation.     

水蒸气蒸馏提取马尾松松针挥发油工艺研究

选用水蒸气蒸馏法提取马尾松松针挥发油,以挥发油的得率为指标,通过L9(34)正交实验法,考察松针投量、松针长度、加水量、提取时间对挥发油得率的影响。结果表明,松针投量对挥发油提取有显著影响(P<0.05),松针长度、加水量、提取时间无显著影响(P>0.05)。最佳提取工艺条件为:松针投量为200 g,松针长度为1.5 cm,加水量为650 mL(料液比为1∶3.25),提取4 h,挥发油得率为0.27%。     

Pine Weevil (Hylobius abietis) Antifeedants from Lodgepole Pine (Pinus contorta)

Pine weevils (Hylobius abietis) fed less on bark of lodgepole pine (Pinus contorta) than on bark of Scots pine (P. sylvestris). Two pine weevil antifeedants, ethyl trans-cinnamate and ethyl 2,3-dibromo-3-phenyl-propanoate, were isolated from bark of lodgepole pine. These two compounds significantly reduced pine weevil feeding in a laboratory bioassay. In field assays, the second compound significantly decreased pine weevil damage on planted seedlings. Ethyl 2,3-dibromo-3-phenylpropanoate has not previously been reported as a natural product.     

Efficiency of Spraying Mountain Pine Cones with Oleoresin of Swiss Stone Pine Cones to Prevent Insect Attack

The difference in cone colonization by specialized insects that had been observed between Swiss stone pine (Pinus cembra L.) and mountain pine (P. uncinata Ram.) prompted us to test whether volatiles and oleoresin of Swiss stone pine cones may serve as a barrier for insect attack. The volatiles emitted by cones of both pine species were sampled using headspace techniques in the French Alps. The cone volatiles of both species essentially consisted of seven similar monoterpenes, but the terpene profiles markedly differed between species. α-Pinene (67% of the total), β-pinene, and limonene + β-phellandrene were dominant in the cone volatiles of Swiss stone pine, while the cone emissions of mountain pine showed no dominant terpenoid. The cone oleoresin of P. cembra significantly differed from cone volatiles by a lower level of α-pinene and higher levels of β-pinene and limonene + β-phellandrene. Field sprays of mountain pine cones with oleoresin extracts of Swiss stone pine cones significantly reduced the overall damage of specialized cone insects. None of the cones sprayed with oleoresin were attacked, whereas 11% and 31% of the unsprayed control cones were damaged by insects. Specific cone damage due to a cone weevil, Pissodes validirostris Gyll. (Coleoptera: Curculionidae), and a cone pyralid, Dioryctria mutatella Fuchs (Lepidoptera: Pyralidae), were significantly decreased in one year. The volatile profile of the sprayed cones differed markedly from that of unsprayed mountain pine cones, especially in the higher level of myrcene. However, the volatile profile of the sprayed cones also differed from that of the oleoresin extract used for spraying. The role of monoterpenes in protecting the sprayed cones from insect attack is discussed.     

Volatiles Associated with Preferred and Nonpreferred Hosts of the Nantucket Pine Tip Moth, Rhyacionia frustrana

Ovipositing female Nantucket pine tip moth, Rhyacionia frustrana, prefer loblolly pine, Pinus taeda L., to slash pine, Pinus elliottii Engelm, except during the first spring following planting of seedlings. Host discrimination by R. frustrana increases as seedlings develop, suggesting that changes in the chemical composition of seedlings may mediate the moth's host preferences. Volatile compounds from slash and loblolly pine seedlings were collected using solid-phase microextraction (SPME) during the first year following planting. Four collection periods coincided with adult emergence and oviposition during each of four annual generations of R. frustrana in the Georgia Coastal Plain. Infestation of slash pine peaked during the second tip moth generation and was similar to the loblolly pine infestation level. By the fourth tip moth generation, slash pine infestation levels had declined and diverged considerably from those of loblolly pine. Significant differences in relative quantities of beta-pinene, alpha-phellandrene, limonene, beta-phellandrene, bornyl acetate, beta-caryophyllene, and an unidentified sesquiterpene occurred between slash and loblolly pine during the fourth generation. However, no strong correlation was observed between any individual compound and host damage that could readily explain the temporal changes in R. frustrana host preference. Gas chromatographic-electroantennographic detection (GC-EAD) analyses of standards identified 19 different seedling-associated compounds that elicited antennal responses from R. frustrana females, indicating that a blend of terpenoids may mediate host discrimination.     

DETERMINATION OF MOISTURE DIFFUSIVITY OF PINE NUT SEEDS

The mechanism of drying and the diffusion of water in fresh pine nut seeds (2.5-2.62mm diameter) were successfully interpreted and modeled by using Fick's law. The initial moisture content of fresh pine nut seed was 23-24% and drying temperatures (45-60°C) were varied, but the drying air was kept at constant velocity and humidity.

The effective diffusivity was estimated from drying rate curves and expressed by an Arhenius relation. In addition, the absorption, and desorption-isotherms for fresh pine nuts were estimated at 20°C at water activity of 0.15-1.00. The isotherms of the fresh pine nuts were estimated in experimental runs.     

湿地松松香的自氧化研究

研究了湿地松松香的自氧化过程,与马尾松松香的自氧化进行比较,并利用气相色谱对二者的自氧化产物进行了分析,阐述它们在自氧化反应前后树脂酸的变化情况。     

钯/竹炭催化剂催化湿地松松香歧化反应研究

研究钯/竹炭(Pb/BC)催化剂对湿地松松香的歧化反应,确定了最佳反应条件,催化剂用量为原料松香质量的 0.4%,搅拌速率 500 r/min,反应温度 270℃,反应时间 3 h,此时湿地松香歧化松香脱氢枞酸达到 56% 以上,枞酸降到 2% 左右,但枞酸指标仍未达到国家标准(枞酸含量≤0.5%)。在其他条件相同,催化剂用量为 0.3% 的反应条件下,采用Pd/BC催化剂也可以催化马尾松松香进行歧化反应,马尾松歧化松香中的枞酸含量为 0.43%, 可以达到国家标准。