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杨木热解过程中的有机挥发物释放 被引量:13
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作者 张梦宁 姜志宏 马中青 《林产工业》 北大核心 2018年第12期29-34,共6页
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:... 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。 展开更多
关键词 杨木 热解 有机挥发物 热重红外联用 热解气质联用
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An investigation of weed seed banks reveals similar potential weed community diversity among three different farmland types in Anhui Province, China 被引量:4
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作者 HE Yun-he GAO Ping-lei QIANG Sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第4期927-937,共11页
Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey ... Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey of weed seed banks was conducted in 2 280 fields at 228 sites of 62 locations representing three different types of farmland(95 paddy, 73 summer-ripe, and 60 autumn-ripe farmlands) along the bank of the Yangtze River in Anhui Province, China. A total of 43 families and 174 species of weeds were found in these weed seed banks. A comparison of the composition of weed groups in the seed banks showed that the species number and density percentage of grass, sedge and broadleaf weed groups were similar among the different types of farmland. The seed banks of all three farmland types shared 71 common weed species, accounting for 40.80% of the total number of species. These common weeds, which were both associated and not associated with crops, accounted for 91.71% of the total dominance degree among all farmland types. The crop-associated weed species were distributed in all soil layers of each farmland type. The Shannon-Wiener index H′(description of species diversity which is more sensitive to dense species) and Pielou's evenness index J(description of species evenness) in summer-ripe farmland were similar to those in autumn-ripe farmland but differed from those in paddy farmland. However, the Simpson's index D(description of species diversity which is more sensitive to sparse species) was similar among all three farmland types. The results of similarity comparison indicated that although the aboveground weed community differed among the different cropping patterns, the weed species composition in the soil seed bank was still similar. Consequently, our results demonstrate that after the implementation of long-term monoculture patterns, weed species compositions in the soil seed bank in different farmlands become homogenized regardless of the crop type. 展开更多
关键词 species compositi on domi nance degree COMM UNITY similarity COMM UNITY variati on ANHUI Province
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Investigation of Ancient and Large Tree Resources in Green Spaces of Urban Parks: A Case Study of Yunqizhujing Park in Hangzhou, China 被引量:5
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作者 CHU Jiamiao LAI Shuifang +1 位作者 ZHONG Tailin LI Yuan 《Journal of Landscape Research》 2012年第10期51-54,共4页
Conservation of ancient and large trees in domestic and overseas cities was compared, ancient and large trees were regarded as important cultural relics playing an important role in optimizing urban natural environmen... Conservation of ancient and large trees in domestic and overseas cities was compared, ancient and large trees were regarded as important cultural relics playing an important role in optimizing urban natural environment and enriching urban humanistic and natural landscapes, and they were also important contents of urban garden works symbolizing urban parks. A case study was carried out Yunqizhujing Park to study conservation of ancient and large trees in park green spaces of Hangzhou City, solutions to current problems were proposed, and constructive suggestions were given for the conservation of ancient and large trees in urban park green spaces. 展开更多
关键词 PARK green SPACES ANCIENT and LARGE valuable TREE RESOURCES Current situation Problems Solutions
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Evaluating the Environmental Health Effect of Bamboo-Derived Volatile Organic Compounds through Analysis the Metabolic Indices of the Disorder Animal Model 被引量:3
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作者 GUO Ming HU Zheng Qing +4 位作者 STRONG P.James SMIT Anne-Marie XU Jian Wei FAN Jun WANG Hai Long 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期595-605,共11页
Objective To identify the bamboo VOCs (volatile organic compounds) effect on animal physiological indices, which associated with human health. Methods GC/MS was used to analyze the volatile organic compounds from Mos... Objective To identify the bamboo VOCs (volatile organic compounds) effect on animal physiological indices, which associated with human health. Methods GC/MS was used to analyze the volatile organic compounds from Moso bamboo (Phyllostachys heterocyla cv. pubescens). The effect of VOCs on environmental health was evaluated by analyzing the metabolic indices of the type 2 diabetic mouse model. Results Spectra of VOC generated by GC/MS were blasted against an in-house MS library confirming the identification of 33 major components that were manually validated. The relative constituent compounds as a percentage of total VOCs determined were alcohols (34.63%), followed by ether (22.02%), aldehyde (15.84%), ketone (11.47%), ester (4.98%), terpenoid (4.38%), and acids (3.83%). Further experimentation established that the metabolic incidence of the disease can be improved if treated with vanillin, leaf alcohol,β-ionone and methyl salicylate. The effects of these VOCs on type 2 diabetes were evident in the blood lipid and blood glucose levels. Conclusion Our model suggests that VOCs can potentially control the metabolic indices in type 2 diabetes mice. This experiment data also provides the scientific basis for the comprehensive utilization of ornamental bamboos and some reference for other similar study of environmental plants. 展开更多
关键词 Phyllostachys heterocyla cv.pubescens Volatile organic compounds Metabolic index Type 2 diabetes
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A Study on Photosynthetic Physiological Characteristics of Six Rare and Endangered Species 被引量:1
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作者 Tailin ZHONG Guangwu ZHAO +2 位作者 Jiamiao CHU Xiaomin GUO Genyou LI 《Agricultural Science & Technology》 CAS 2014年第8期1265-1270,共6页
The parameters of gas exchange and chlorophyl fluorescence in leaves of six rare and endangered species Neolitsea sericea, Cinnamomum japonicum var. cheni , Sinojackia microcarpa, Discocleidion glabrum var. trichocarp... The parameters of gas exchange and chlorophyl fluorescence in leaves of six rare and endangered species Neolitsea sericea, Cinnamomum japonicum var. cheni , Sinojackia microcarpa, Discocleidion glabrum var. trichocarpum, Parrotia sub-aequalis, Cercidiphyl um japonicum were measured in fields. The results showed that there were significant differences in photosynthetic capacity, intrinsic water use effi-ciency (WUEi ), the efficiency of primary conversion of light energy of PSⅡ and its potential activity, the quantum yield of PSⅡ electron transport, and the potential ca-pacity of heat dissipation among the six species. However, there was no significant difference in WUE. The highest values of net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (gs) occurred in D. glabrum var. trichocarpum and the lowest in S. microcarpa. On the contrary, D. glabrum var. trichocarpum had the lowest WUE, intrinsic water use efficiency (WUEi ) and S. microcarpa had the highest. The results indicated that D. glabrum var. trichocarpum had higher photo-synthetic capacity and poorer WUE, while S. microcarpa had lower photosynthetic capacity and greater WUE. Furthermore, the mean values of maximal fluorescence (Fm), potential efficiency of primary conversion of light energy of PSⅡ (Fv/Fm),ΦPSⅡ, actual efficiency of primary conversion of light energy of PSⅡ (F′v/F′m) and non-photochemical quenching coefficient (NPQ) were the highest in S. micro-carpa, indicating that its PSⅡ had higher capacity of heat dissipation and could prevent photosynthetic apparatus from damage by excessive light energy. Correlation analysis showed that there were significant correlations among photosynthetic physi-ological parameters. However, the initial fluorescence (Fo) was not significantly cor-related with any other parameters. This study also revealed the extremely significant positive correlations between Pn and Tr, gs, apparent quantum yield (AQY), be-tween Tr and gs, between light saturation point (LSP) and AQY, between Fv/Fm and Fm, between ΦPSⅡ and photochemical quenching coefficient (qp), between Tr, gs and LSP, AQY. However, WUEi was significantly negatively correlated with Tr, gs, Pn, LSP and AQY. 展开更多
关键词 Gas exchange Chlorophyll fluorescence Water use efficiency Rare andendangered species
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The Wigner distribution function of a super Lorentz–Gauss SLG_(11) beam through a paraxial ABCD optical system
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作者 周益民 周国泉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期272-280,共9页
An orthonormal beam family of super Lorentz-Gauss (SLG) beam model is proposed to describe the higher-order mode beams with high divergence, which are generated by a high power diode laser. Here we consider the simp... An orthonormal beam family of super Lorentz-Gauss (SLG) beam model is proposed to describe the higher-order mode beams with high divergence, which are generated by a high power diode laser. Here we consider the simplest case of the SLG beams, where there are four mutually orthogonal SLG beams, namely SLG00, SLG01, SLG10, and SLGll beams. The SLG00 beam is just the Lorentz-Gauss beam. Based on the Collins integral formula and the Hermite-Gaussian expansion of a Lorentz function, an analytical expression for the Wigner distribution function (WDF) of an SLG11 beam through a paraxial ABCD optical system is derived. The properties of the WDF of an SLG11 beam propagating in free space are demonstrated. The normalized WDFs of an SLG11 beam at the different spatial points are depicted in several observation planes. The influence of the beam parameter on the WDF of an SLGI 1 beam in free space is analyzed at different propagation distances. The second-order moments of the WDF of an SLG11 beam in free space are also examined. This research reveals the propagation properties of an SLGll beam from another perspective. The WDFs of SLG01 and SLG10 beams can be easily obtained by using the WDFs of Lorentz-Gauss beam and the SLG11 beam. 展开更多
关键词 Wigner distribution function super Lorentz-Gauss beam paraxial ABCD optical system
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The adaptability of three Arctic microalgae to different low temperatures
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作者 夏利花 何剑锋 +3 位作者 张芳 高岩 张汝民 崔世开 《Chinese Journal of Polar Science》 2010年第2期193-203,共11页
In order to study the adaptability of Arctic microalgae to different environmental temperatures,the growth curves and antioxidase system of three microalgae (Skeletonema marinoi.Chlorella sp.and Chlamydomonas sp.) t... In order to study the adaptability of Arctic microalgae to different environmental temperatures,the growth curves and antioxidase system of three microalgae (Skeletonema marinoi.Chlorella sp.and Chlamydomonas sp.) that were separated from the Ny-(?)lesund,the high Arctic,at different low temperatures (0℃,4℃and 8℃) were determined.The result showed that the adaptability of the microalgae to temperatures depended on the species.The growth rate,SOD and CAT activities of Skeletonema marinoi were the highest at 4℃, but MDA content was the lowest.The growth rate and enzyme activity of Chlorella sp.were the highest at 8℃,while the lowest MDA content presented at 0℃.The growth of Chlamydomonas sp.at the different temperatures was not so significant,the lowest MDA content presented at 8℃.The change of antioxidase system also depended on species and temperatures.Three indexes of antioxidase system of Skeletonema marinoi between 0℃and 4℃showed extremely significant difference(p0.01).SOD activity of Skeletonema marinoi and Chlorella sp.between 0℃and 8℃showed significant difference(p0.05), and the other two indexes of them differed insignificantly.Antioxidase systems of Chlamydomonas sp.at the three temperatures differed insignificantly.In conclusion, the three microalgae had good adaptability to the three temperatures; their MDA content presented a low level,and had unique physiological mechanism to adapt to the environment with different low temperatures. 展开更多
关键词 Arctic microalga ADAPTABILITY MDA SOD CAT
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Influences of SiO2/Na2O Molar Ratio on Aging and Chemical Modification of Water Glass
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作者 Huan Yang Hailan Xu +4 位作者 J. Kriss Frank Guangtong Xu Weiwei Huan Chaoying Ni Yuxiang Yang 《Open Journal of Inorganic Chemistry》 2016年第2期125-134,共10页
In this paper, the content of water glass before and after adding modifying agent was measured by Trimethylsilyl-gas-chromatography. The experimental results showed that different modulus of water glass could generate... In this paper, the content of water glass before and after adding modifying agent was measured by Trimethylsilyl-gas-chromatography. The experimental results showed that different modulus of water glass could generate different content of mono-silicate acid and oligomeric silicate acid in water glass. After a period of storage, different modulus of water glass led to decrease of silicate content at different levels. Because higher content of Na<sub>2</sub>O in water glass tended to incur the alkaline polymerization, the occurrence of depolymerization of silicate species would lead to an increase of oligomeric silicate species, resulting in a drawback of silicate species content after a period of storage. And contrary to that, lower content of Na<sub>2</sub>O in water glass tended to incur the acidic polymerization. When the modifying agent was added to the newly made water glass, the amount of mono-silicate acid and oligomeric silicate acid also decreased. In modified water glass, the change of each silicate acid species was less than that in unmodified water glass. These results showed that the modifying agent retarded the aging of water glass. It had remarkable significance on the theory and practical application of water glass chemistry. 展开更多
关键词 Water Glass MODULUS Polymerization Mechanism Chemical Modification TMS-GC Method
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Variation in glucosinolates in pak choi cultivars and various organs at different stages of vegetative growth during the harvest period 被引量:2
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作者 Biao ZHU Jing YANG Zhu-jun ZHU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第4期309-317,共9页
Glucosinolates(GSs) play an important role in plant defense systems and human nutrition.We investigated the content and composition of GSs in the shoots and roots of seven cultivars of pak choi.We found that 'Si Y... Glucosinolates(GSs) play an important role in plant defense systems and human nutrition.We investigated the content and composition of GSs in the shoots and roots of seven cultivars of pak choi.We found that 'Si Yue Man' had the highest total and aliphatic GS contents in the shoots and the highest benzenic GS content in the roots,'Shanghai Qing' contained the highest amounts of benzenic and total GS contents in the roots,while 'Nanjing Zhong Gan Bai' had the lowest benzenic,indole,and total GS contents in both the shoots and roots.Therefore,the 'Si Yue Man' cultivar appears to be a good candidate for future breeding.Variation between the shoots and roots was also examined,and a significant correlation among the total,aliphatic,and some individual GSs was found,which is of value in agricultural breeding.GS concentrations of the leaf,petiole,and root increased dramatically during the period of rapid growth of the dry matter of the plant 10 to 20 d after transplantation,reaching peak values on Day 20 and decreasing on Day 25.We conclude that the pak choi should be harvested and consumed from 20 to 25 d after transplantation to take advantages of the high GS content in the plant. 展开更多
关键词 GLUCOSINOLATE Pak choi CULTIVAR ORGAN Growth stage
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Plant MicroRNAs and Development 被引量:14
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作者 Gang Wu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2013年第5期217-230,共14页
MicroRNAs(miRNAs) are a class of about 20—24 nt small non-coding RNAs that can regulate their target gene expression transcriptionally and posttranscriptionally.There are an increasing number of studies describing ... MicroRNAs(miRNAs) are a class of about 20—24 nt small non-coding RNAs that can regulate their target gene expression transcriptionally and posttranscriptionally.There are an increasing number of studies describing the identification of new components and regulatory mechanisms involved in the miRNA biogenesis and effector pathway as well as new functions of miRNAs in plant development. This review mainly focuses on the components involved in this pathway,and the developmental defects associated with the corresponding mutations.Some functions of important miRNAs in plant development,together with the modes of miRNA action,are also discussed in this review to describe the recent advance in this area. 展开更多
关键词 Plant miRNAs Biogenesis Function Development
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Six newly recorded species of whitefly(Hemiptera:Aleyrodidae) from China 被引量:1
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作者 Jirui Wang Yuzhou Du Zhihong Xu 《Zoological Systematics》 CSCD 2016年第4期427-438,共12页
Six species of whitefly (Hemiptera: Aleyrodidae), namely Aleuromarginatus corbettiaformis Martin, Aleurotrachelus machili Takahashi, Asialeyrodes indica Sundararaj & David, Asterobemisia takahashii Danzig, Pealius... Six species of whitefly (Hemiptera: Aleyrodidae), namely Aleuromarginatus corbettiaformis Martin, Aleurotrachelus machili Takahashi, Asialeyrodes indica Sundararaj & David, Asterobemisia takahashii Danzig, Pealius akebiae (Kuwana) and Tetraleurodes neemani Bink-Moenen, are reported as new records to Chinese fauna and redescribed with their morphology, illustrations and photographs of scanning electron microscope (SEM). The specimens are deposited in the Insect Collection of Yangzhou University. 展开更多
关键词 HEMIPTERA ALEYRODIDAE TAXONOMY new record China.
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Research Advance in Construction of Forest Genetic Linkage Map
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作者 Chen Zheng Tong Zaikang 《Chinese Forestry Science and Technology》 2012年第3期48-49,共2页
Forest genetic maps are an important component within the forest biologist’s toolkit, underpinning forest improvement programs.The estimation of forest genetic maps is a conceptually simple yet computationally comple... Forest genetic maps are an important component within the forest biologist’s toolkit, underpinning forest improvement programs.The estimation of forest genetic maps is a conceptually simple yet computationally complex problem,due to long growth period and high heterozygosis and genetic load of forest trees.At present,some genetic maps of trees have been constructed.This paper reviewed the process of forest genetic map construction,highlighting its uniqueness,and pointed out the problems that might rise in mapping.Finally, prospect was made for constructing the high density genetic map of trees. 展开更多
关键词 FOREST tree GENETIC map molecular MARKER MAPPING POPULATION MAPPING strategy
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