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越冬时期雪松叶片中SOD、CAT及可溶性糖的变化 被引量:14
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作者 左宝峰 冀支林 姚延梼 《山西农业大学学报(自然科学版)》 CAS 2007年第3期238-240,298,共4页
研究自然状态和采取搭棚保护后的引种雪松,在越冬时期叶片内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)以及可溶性糖含量的变化规律。结果表明:当年引种雪松在越冬期间叶片中SOD、CAT的活性变化曲线呈“M”状,可溶性糖的含量变化曲线呈抛物... 研究自然状态和采取搭棚保护后的引种雪松,在越冬时期叶片内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)以及可溶性糖含量的变化规律。结果表明:当年引种雪松在越冬期间叶片中SOD、CAT的活性变化曲线呈“M”状,可溶性糖的含量变化曲线呈抛物状。在低温胁迫下,SOD、CAT活性及可溶性糖含量的变化直接影响着雪松抗寒能力的高低,是影响雪松北方引种驯化成功的重要原因之一。 展开更多
关键词 雪松 超氧化物歧化酶 过氧化氢酶 可溶性糖
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昆明地区典型乔木主要挥发性有机物释放规律 被引量:14
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作者 宁平 郭霞 +2 位作者 田森林 史建武 孙长增 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第3期1290-1296,共7页
采用顶空活体采样法,于2011-04—2011-05采用电子鼻对昆明地区圆柏和雪松2种乔木植物挥发性有机物(BVOCS,包括α-蒎烯和异戊二烯)进行采集和实时分析,同时对天气情况、气温和湿度等参数进行观测。研究结果表明:2种乔木的BVOCS释放量明... 采用顶空活体采样法,于2011-04—2011-05采用电子鼻对昆明地区圆柏和雪松2种乔木植物挥发性有机物(BVOCS,包括α-蒎烯和异戊二烯)进行采集和实时分析,同时对天气情况、气温和湿度等参数进行观测。研究结果表明:2种乔木的BVOCS释放量明显不同,但均以排放异戊二烯为主;2种乔木BVOCS释放均具有显著的小时变化规律,在圆柏释放BVOCS时刻变化曲线上,4月均表现为"两峰两谷型",5月均表现为"三峰两谷型";雪松释放BVOCS的时刻变化曲线表现为"两峰一谷型",而最高值均出现在中午;2种乔木对典型BVOCS的释放均具有显著的日间变化,4月的变化趋势比5月的明显;BVOCS的释放与气温的变化规律一致,其中温度在24~35℃、相对湿度在45%~60%时,BVOCs释放量最大,且4月时较5月时大;2种乔木BVOCS释放量与温度显著正相关,α-蒎烯和异戊二烯的释放量与相对湿度的相关性,前者为正相关,后者为负相关,温度的相关性较湿度大。 展开更多
关键词 圆柏 雪松 植物挥发性有机物 释放规律 相对湿度
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雪松的挥发性物质成分及抑菌效益研究 被引量:13
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作者 盖苗苗 周春玲 +1 位作者 曲宁 郑锋先 《中国农学通报》 CSCD 北大核心 2010年第7期311-313,共3页
为了研究雪松的挥发性有机物及其抑菌效果,采用固相微萃取和GC/MS分析相结合的方法对雪松叶片的挥发性有机物进行了鉴定,共鉴定出31种化学成分,主要为1R-α-蒎烯、α-蒎烯、月桂烯、柠檬烯、石竹烯等;采用室内水插枝法研究了雪松对细菌... 为了研究雪松的挥发性有机物及其抑菌效果,采用固相微萃取和GC/MS分析相结合的方法对雪松叶片的挥发性有机物进行了鉴定,共鉴定出31种化学成分,主要为1R-α-蒎烯、α-蒎烯、月桂烯、柠檬烯、石竹烯等;采用室内水插枝法研究了雪松对细菌、真菌、放线菌的抑制作用,结果表明雪松具有较强的清除微生物能力,其能力随着季节的变化而不同,这种差异与其挥发性有机物的成分及含量有关。 展开更多
关键词 雪松 挥发性有机物 抑菌效益 固相微萃取 GC/MS
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雪松松针提取物抑菌活性及抑菌稳定性研究 被引量:9
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作者 楼英彪 陈菲 高素华 《中国药业》 CAS 2013年第8期39-40,共2页
目的研究雪松松针不同溶剂提取物的抑菌效果和抑菌稳定性。方法分别用水、95%乙醇、乙酸乙酯、石油醚对雪松松针进行提取,采用滤纸片法比较不同溶剂提取物的抑菌活性。采用不同体积分数的乙醇提取,确定提取雪松松针抑菌成分的最适溶剂... 目的研究雪松松针不同溶剂提取物的抑菌效果和抑菌稳定性。方法分别用水、95%乙醇、乙酸乙酯、石油醚对雪松松针进行提取,采用滤纸片法比较不同溶剂提取物的抑菌活性。采用不同体积分数的乙醇提取,确定提取雪松松针抑菌成分的最适溶剂。探讨热处理、介质pH和糖含量对松针提取物抑菌稳定性的影响。结果松针50%乙醇的提取物抑菌活性最佳,热处理对抑菌活性无明显影响,介质pH和糖含量可在一定程度上影响抑菌活性。结论雪松松针提取物具有较好的抑菌作用,可作为一种天然防腐剂加以开发利用。 展开更多
关键词 雪松 提取物 抑菌活性 稳定性
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维吉尼亚雪松精油的GC-MS分析及体外药理活性研究 被引量:7
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作者 席祖卫 王雨佳 +3 位作者 陈金虎 王梦如 李婷 刘衡 《药物分析杂志》 CAS CSCD 北大核心 2022年第2期335-341,共7页
目的:对市售维吉尼雪松精油主要挥发性成分分析,并探究其体外药理活性。方法:采用气相-质谱联用法,色谱柱为Agilent HP-5MS(250μm×30 m,0.25μm),载气为高纯氦气,进样量0.2μL;分流比10∶1;柱流量1.0 mL·min^(-1),进样口温度... 目的:对市售维吉尼雪松精油主要挥发性成分分析,并探究其体外药理活性。方法:采用气相-质谱联用法,色谱柱为Agilent HP-5MS(250μm×30 m,0.25μm),载气为高纯氦气,进样量0.2μL;分流比10∶1;柱流量1.0 mL·min^(-1),进样口温度220℃。离子源为EI,离子源温度230℃,电离能量70 eV,质量扫描范围m/z 12~550,溶剂延迟3 min;采用面积归一化法测定各组分的相对含量;牛津杯法测定抑菌圈的大小,评价其对金黄色葡萄球菌、大肠埃希菌及白色念珠菌的体外抑菌活性;通过建立脂多糖(lipopolysaccharide,LPS)刺激RAW264.7细胞系炎症模型,探究其对巨噬细胞相关炎症因子TNF-α表达量的影响;噻唑蓝(Methyl Thiazolyl Tetrazolium,MTT)法测定其对HT-29肿瘤细胞体外细胞毒活性。结果:从维吉尼亚雪松精油样品中共检测出21个成分,占总峰面积的95.67%,主要成分为雪松醇(26.58%)、α-雪松烯(24.05%)、顺罗汉柏烯(23.46%)等萜烯类和萜醇类化合物;维吉尼亚雪松精油可显著提高TNF-α的表达量,呈成剂量依赖性抑制HT-29细胞的增殖,但对3个菌敏感度均不高。结论:维吉尼亚雪松精油成分丰富,具有一定的抗菌活性,同时能促进LPS诱导RAW264.7细胞向M1型极化的作用,并有较好的抗HT-29肿瘤细胞增殖作用。 展开更多
关键词 雪松 精油 气相色谱-质谱 抗菌 M1型极化
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雪松枝枯病病原和生物学特性研究 被引量:8
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作者 高智辉 王云果 +4 位作者 韩丽 张刚龙 张春霞 韩养贤 肖琦 《西北林学院学报》 CSCD 北大核心 2005年第3期127-130,共4页
在陕西关中地区的雪松(Cedrusdeodara)上发生枝枯病,主要使雪松树的主干和侧枝枯死。(1)经鉴定该病是由子囊菌亚门的茶藨子葡萄座腔菌(Botryosphaeriaribis)所致,无性为半知菌亚门的聚生小穴壳菌(Dothiorellagregaria);(2)该菌适宜生长... 在陕西关中地区的雪松(Cedrusdeodara)上发生枝枯病,主要使雪松树的主干和侧枝枯死。(1)经鉴定该病是由子囊菌亚门的茶藨子葡萄座腔菌(Botryosphaeriaribis)所致,无性为半知菌亚门的聚生小穴壳菌(Dothiorellagregaria);(2)该菌适宜生长的温度为27℃,pH为6;营养状况对孢子萌发影响小;(3)化学防治能有效的控制雪松枝枯病。 展开更多
关键词 雪松 病原菌 生物学测定
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Longevity of Juniperus procera seed lots under different storage conditions: implications for ex situ conservation in seed banks 被引量:5
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作者 Negash Mamo Diriba Nigusie +2 位作者 Mulualem Tigabu Demel Teketay Miftah Fekadu 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第3期453-459,共7页
Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the e... Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the effects of seed sources and storage temperature on the longevity of Juniperus procera seed lots through collection and preservation of seeds in seed banks. Seeds were collected from nine sites across the species natural distribution in Ethiopia and stored in four warehouses: modern cold room (5℃), mud house (15℃), concrete block house (17℃ or corrugated iron house (20℃) for 42 months. Every three months, a random sample of stored seeds were drawn and tested for germination. A highly significant variation (p 0.01) in germination of stored seeds was observed among different storage environments, seed lots, and duration of storage. Over the storage period, seeds stored in the cold room had the highest mean percentage germination, followed by the mud house, corrugated house and blocket house. The cold room (41%) and the mud house (38%) maintained the same level of germination as the intitial germination of the seedlotds (42%). The variation in longevity of stored seeds was significnatly correlated with the initial germination of seed lots (r 0.80; p 0.01). Cold storage also resulted in enhancement of germination through its stratification effect that terminated the non-deepphysiological dormancy of juniper seeds. In conclusion, seed lots with good initial germination can be effectively stored in cold room (5℃) up to four years. In the absence of modern cold stores, mud houses can be used as a good alternative to store seeds at local level. 展开更多
关键词 GERMINATION African pencil cedar Ethiopia seed zones seed storage
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Spatial Variations in Particle Size and Magnetite Concentration on Cedar Beach:Implications for Grain-Sorting Processes,Western Lake Erie,Canada 被引量:3
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作者 ZHANG Shuwei Maria T. CIOPPA ZHANG Shihong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1520-1532,共13页
This study examined spatial variations in the concentration,grain size and heavy mineral assemblages on Cedar Beach(Lake Erie,Canada).Magnetic studies of heavy mineral-enriched,dark-reddish sands present on the beac... This study examined spatial variations in the concentration,grain size and heavy mineral assemblages on Cedar Beach(Lake Erie,Canada).Magnetic studies of heavy mineral-enriched,dark-reddish sands present on the beach showed that magnetite(~150μm) is the dominant magnetic mineral.Surficial magnetic susceptibility values defined three zones:a lakeward region close to the water line(Zone 1),the upper swash zone(Zone 2) and the region landwards of the upper swash zone (Zone 3).Zone 2 showed the highest bulk and mass susceptibility(κ,χ) and the highest mass percentage of smaller grain-size(250μm) fractions in the bulk sand sample.Susceptibility(i.e.κandχ) values decreased and grain size coarsened from Zone 2 lakewards(into Zone 1) and landwards (into Zone 3),and correlated with the distribution of the heavy mineral assemblage,most probably reflecting preferential separation of large,less dense particles by waves and currents both along and across the beach.The eroded western section of Cedar Beach showed much higher concentrations of heavy minerals including magnetite,and finer sand grain sizes than the accreting eastern section, suggesting that magnetic techniques could be used as a rapid,cost-effective way of examining erosion along sensitive coastline areas. 展开更多
关键词 magnetic susceptibility magnetite concentration grain size grain-sorting processes cedar Beach Lake Erie
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Fluoro-functionalized plant biomass adsorbent:Preparation and application in extraction of trace perfluorinated compounds from environmental water samples
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作者 Xi Tan Yan Shi +5 位作者 Chun-Feng Ma Quan Chi Yu-Hang Yang Wen-Xiang Zhang Hua-Ming Xiao Xian Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第3期703-715,共13页
Perfuorinated compounds(PFCs)are toxic and widely present in the environment,and therefore effective adsorbents are required to remove PFCs from environmental water.In the present study,a new type of fuorinated biomas... Perfuorinated compounds(PFCs)are toxic and widely present in the environment,and therefore effective adsorbents are required to remove PFCs from environmental water.In the present study,a new type of fuorinated biomass materials was synthesized via an ingenious fuorosilanization reaction.These adsorbents were applied for the adsorption of 13typical PFCs,including perfuorocarboxylic acids(PFCAs)and perfuorosulfonic acids(PFSAs).By comparing their adsorption performance,Fluorinated cedar slag(FCS)was discovered to have the best absorption efficiency and enabled highly efficient enrichment of PFCs.The adsorption recovery of FCS with the investigated PFCs is greater than 90%under the optimal adsorption condition.Ascribed to the high affinity of F-F sorbent-sorbate interaction,FCS had good adsorption capacities of PFCs from aqueous solution,with the maximum adsorption capacity of 15.80 mg/g for PFOS and 10.71 mg/g for PFOA,respectively.Moreover,the adsorption time could be achieved in a short time(8 min).Using the FCS absorbent,an innovative FCS-solid phase extraction assisted with high performance liquid chromatography-electrospray-tandem mass spectrometry(FCS-SPE-HPLC-ESI-MS/MS)method was first developed to sensitively detect PFCs in the environmental water samples.The intra-day and inter-day recovery rates of the 13 compounds ranged from 90.7%-104.3%,with the RSD of 2.1%-4.7%(intra-day)and 2.5%-8.5%(inter-day),respectively.This research demonstrates the potential of the newly fuoro-functionalized plant biomass to adsorb PFCs from environmental water,with the advantages of high adsorption efficiencies,high antiinterference,easy operation and low economic cost. 展开更多
关键词 Fluoro-functionalized biomass Perfuorinated compounds(PFCs) Adsorption efficiency Mass spectrometry(MS) Fluorinated cedar slag(FCS)
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Development and evaluation of a quadruple real-time fluorescence-based quantitative reverse transcription polymerase chain reaction assay for detecting Langya, Mojiang, Nipah, and Cedar viruses
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作者 Wenjun He Tian Ma +5 位作者 Yalan Wang Weifang Han Jun Liu Wenwen Lei Le Zhang Guizhen Wu 《Biosafety and Health》 CAS CSCD 2024年第2期80-87,共8页
The emerging viruses within the genus Henipavirus in the family Paramyxoviridae pose a great threat to public biosafety.To develop a quadruple real-time fluorescence-based quantitative reverse transcription polymerase... The emerging viruses within the genus Henipavirus in the family Paramyxoviridae pose a great threat to public biosafety.To develop a quadruple real-time fluorescence-based quantitative reverse transcription polymerase chain reaction(qRT-PCR)assay is pivotal for the early warning of the potential of zoonotic infectious diseases.Specific primers and probes were designed for the relatively conserved regions based on whole genome sequences of Langya virus(LayV),Mojiang virus(MojV),Nipah virus(NiV),and Cedar virus(CedV),followed by the establishment of a quadruple real-time fluorescence-based qRT-PCR detection method.No cross-reactivity was observed with other viral nucleic acids.The optimal linear detection range for LayV,MojV,NiV,and CedV was 10^(1)-10^(8)copies/μL,and the lower limit of detection was 10 copies/μL.Three different DNA concentrations of LayV,MojV,NiV,and CedV(10^(4),10^(5),and 10^(6)copies/μL)were tested 14 times,achieving good repeatability.The standard deviation of the cycle threshold values for each concentration was<0.5 and the coefficient of variation was<3%.Furthermore,the amplification efficiency of quadruple real-time fluorescence-based qRT-PCR was>90%,and the correlation coefficient was>0.99.The established quadru-ple real-time fluorescence-based qRT-PCR assay for the detection of LayV,MojV,NiV,and CedV exhibits good sensitivity,specificity,and repeatability.Therefore,it can be used to detect Henipavirus and other related clinical specimens. 展开更多
关键词 Real-time fluorescence-basedq RT-PCR Langyavirus Mojiang virus Nipahvirus cedar virus
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酶法提取针叶胶 被引量:6
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作者 黄天芳 胡芬 《孝感学院学报》 2008年第6期20-23,共4页
以松针为材料,用正交实验分析了影响纤维素酶活力的三个主要因素,并根据正交实验结果,对单个因素的多个水平进行了比较分析,结果表明:温度是影响纤维素酶提取针叶胶的最主要因素;酶用量高于20U/g以后,对针叶胶提取率影响不大;在温度50℃... 以松针为材料,用正交实验分析了影响纤维素酶活力的三个主要因素,并根据正交实验结果,对单个因素的多个水平进行了比较分析,结果表明:温度是影响纤维素酶提取针叶胶的最主要因素;酶用量高于20U/g以后,对针叶胶提取率影响不大;在温度50℃、pH5.2、酶用量20 U/g条件下,用纤维素酶处理后,其提取针叶胶的提取率最高。 展开更多
关键词 纤维素酶 雪松 针叶胶 提取
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Wettability modification effects on relative permeability end-points:Comparative analysis of surfactant agents for enhanced oil recovery
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作者 Erfan Hosseini Negar Hosseini Mohammad Sarmadivaleh 《Petroleum Research》 EI 2024年第2期206-218,共13页
This research examines the impact of wettability alteration on the end points of relative permeability,a crucial property of fluids and porous media that influences the displacement processes of immiscible fluids thro... This research examines the impact of wettability alteration on the end points of relative permeability,a crucial property of fluids and porous media that influences the displacement processes of immiscible fluids through such media.The estimation of the mobility ratio for oil recovery relies on these end points,which are influenced by connate water saturation and residual oil saturation.To investigate this relationship,carbonate rock is generally subjected to wettability alteration using surfactant agents,and core flooding is employed to determine the relative permeability before and after the alteration.The wettability of the rock is commonly assessed through contact angle measurements.Two surfactants,TritonX-100(Tx-100)and Cedar,were tested in reducing the wettability of the porous media for oil.The contact angle measurements revealed that Tx-100 was more effective for this purpose than Cedar.Furthermore,the relative permeability tests indicated that both surfactants decreased residual oil saturation,but Tx-100 also improved system pressure.In contrast,Cedar reduced residual oil saturation but increased system pressure,possibly because of its high viscosity.The results also demonstrate that injecting Tx-100 leads to a 14%increase in ultimate oil recovery compared with water injection,while Cedar injection increased the recovery factor by 5%.This difference may be attributed to the incomplete coverage of the pore wall by Cedar or its weaker chemical structure than Tx-100.Notably,in carbonate cores,neither non-ionic surfactant enhanced oil recovery. 展开更多
关键词 Wettability alteration Relative permeability Core flooding TX-100 cedar Contact angle
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从雪松针叶中提取针叶胶的研究 被引量:5
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作者 黄天芳 程世才 +1 位作者 朱丹丹 李青 《孝感学院学报》 2005年第6期16-18,共3页
针叶胶的开发利用潜力很大。比较分析了不同的热水浸提法从雪松针叶中提取胶体物质的工艺条件,结果表明,在浸提温度为80℃,浸提料液比为1∶20,浸提时间为21 h时,雪松针叶胶的提取效果最好。
关键词 针叶胶 多糖胶 浸提法 雪松
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雪松松针总三萜皂苷提取工艺的研究 被引量:6
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作者 许文凤 王文君 +2 位作者 徐明生 欧阳克蕙 罗秋水 《食品工业科技》 CAS CSCD 北大核心 2011年第6期312-314,共3页
以雪松松针为材料,主要研究了醇提法对雪松松针中总三萜皂苷的提取。选取浸提温度、浸提时间、料液比、乙醇浓度进行单因素实验,并在此基础上进行正交实验,由正交实验极差分析得出最佳提取工艺条件为:浸提温度为70℃、浸提时间为2h、料... 以雪松松针为材料,主要研究了醇提法对雪松松针中总三萜皂苷的提取。选取浸提温度、浸提时间、料液比、乙醇浓度进行单因素实验,并在此基础上进行正交实验,由正交实验极差分析得出最佳提取工艺条件为:浸提温度为70℃、浸提时间为2h、料液比1:20、乙醇浓度为70%。 展开更多
关键词 雪松 三萜皂苷 提取工艺 得率
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3D皮肤模型的构建及其在化妆品原料活性物功效检测中的应用研究 被引量:6
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作者 宋肖洁 周春霞 吴越 《日用化学工业》 CAS CSCD 北大核心 2017年第11期633-636,650,共5页
使用Mimedisc作为支架,接种正常人真皮成纤维细胞,经过3周培养形成类似真皮结构,然后在其上接种正常人表皮角质细胞,依次经过浸没培养阶段和气-液相培养阶段,最终在体外形成3D皮肤结构模型。通过Masson染色及一系列免疫荧光染色显示此3... 使用Mimedisc作为支架,接种正常人真皮成纤维细胞,经过3周培养形成类似真皮结构,然后在其上接种正常人表皮角质细胞,依次经过浸没培养阶段和气-液相培养阶段,最终在体外形成3D皮肤结构模型。通过Masson染色及一系列免疫荧光染色显示此3D皮肤模型有近似真实皮肤的结构及关键蛋白表达。以此模型为工具研究了活性物喜马拉雅雪松精粹对皮肤真表皮连接处(DEJ)的作用。结果显示喜马拉雅雪松精粹可以明显提高表皮的厚度,增加皮肤抵抗外界环境的屏障能力,并且可以显著促进DEJ重要蛋白层粘连蛋白5(Laminin 5)和VII型胶原蛋白(Collagen VII,Col VII)的表达,使Laminin 5上调20%,Col VII上调47%,具有应用于抗衰老类化妆品的潜力。 展开更多
关键词 化妆品原料 雪松 3D皮肤模型 真表皮连接处 抗衰老
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Cedar Pollen and Cedar Pollinosis 被引量:1
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作者 Yin Min(殷 敏) Cheng Lei(程 雷) Akira Miyoshi 1 Peng Jieren(彭解人) 2 Chen Zhibin(陈智斌)\ Shi Haibo(时海波)\ T Sambe 3\ Y Taguchi 4\ N Sahashi 5 Department of Otolaryngology, the First Affiliated Hospital of Nangjing Medical University, Nanj 《Journal of Nanjing Medical University》 2000年第1期41-44,共4页
Objective To investigate the prevalence of cedar pollinosis in China, and compare Cryptomeria fortunei(Cf) with Cryptomeria japonica (Cj) morphologically. Methods\ An epidemiological survey on nasal allergy was carri... Objective To investigate the prevalence of cedar pollinosis in China, and compare Cryptomeria fortunei(Cf) with Cryptomeria japonica (Cj) morphologically. Methods\ An epidemiological survey on nasal allergy was carried out among 1 660 primary and middle school students and 1 620 university students, including questionnaire investigation, nasal inspection by the same doctor and scratch test with the allergen extract of Cj. The pollen of Cf and Cj were observed by optical and electron microscope. The genes of chloroplast of them were analysed. Results ①The total positive rate of cedar pollen scratch test was 4.2%. 55 cases of nasal allergy were confirmed according to the criteria of diagnosis, in which 8 cases showed positive reaction to Cj and only 1 case was hypersentive to it. ②No significant distinction between Cf and Cj was found by optical and electron microscope and no difference in gene analysis was found. Conclusion\ ①Cedar pollinosis does exist in China. It′s low prevbalence is related to the low quantity of cedar pollen.②Cf and Cj are of the same family and genus. ③There may be an increasing tendency of cedar pollinosis in China.\; 展开更多
关键词 cedar cedar pollen cedar pollinosis EPIDEMIOLOGICAL
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豫西南香椿苗期优良无性系选择研究 被引量:4
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作者 翟文继 沈元勤 《河南林业科技》 2018年第1期18-21,共4页
对收集的豫西南52个香椿优良种质资源播种繁育,同时进行超级苗选择,通过嫁接方法,对超级苗进行无性系化作一级筛选、二级筛选,最终选出18个优良无性系,为进一步香椿良种选育提供基础资料。
关键词 香椿 优良种质资源 苗期 选择
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微波辅助乙醇提取雪松树中原花青素的工艺研究 被引量:4
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作者 秦涛 王兴涛 刘军海 《食品与发酵科技》 CAS 2009年第3期33-36,共4页
研究了从雪松树叶和树皮微波辅助提取原花青素的工艺,考察了不同提取剂对得率的影响,结果表明,乙醇作为提取剂比较合适。通过正交试验优化了工艺条件,结果表明,提取雪松树皮中原花青素的最佳工艺条件为:提取温度为60℃,微波处理功率为10... 研究了从雪松树叶和树皮微波辅助提取原花青素的工艺,考察了不同提取剂对得率的影响,结果表明,乙醇作为提取剂比较合适。通过正交试验优化了工艺条件,结果表明,提取雪松树皮中原花青素的最佳工艺条件为:提取温度为60℃,微波处理功率为100W,微波处理时间40s,提取时间6h,原花青素的得率为8.75%。微波辅助法提取雪松树叶中原花青素的最佳工艺条件为:提取温度为60℃,微波处理功率为200W,微波处理时间40s,提取时间5h,原花青素的得率为9.84%。 展开更多
关键词 雪松树 原花青素 微波辅助 提取
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Impact of a Low Severity Fire on Soil Organic Carbon and Nitrogen Characteristics in Japanese Cedar Soil, Yamagata Prefecture, Japan 被引量:1
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作者 Felix Seidel M. Larry Lopez C +1 位作者 Georg Guggenberger Yoshihiro Nobori 《Open Journal of Forestry》 2017年第2期270-284,共15页
Slash and burn practices are widely used around the globe with different degrees of success which are mostly related to the impact of fire on soil properties. In Japan slash and burn practises, known as Yakihata, have... Slash and burn practices are widely used around the globe with different degrees of success which are mostly related to the impact of fire on soil properties. In Japan slash and burn practises, known as Yakihata, have a long history and are still used in Yamagata Prefecture today. The purpose of this study was to determine the impact of a low severity controlled fire underneath Japanese cedar (Cryptomeria japonica) on brown forest soil (Cambisol). Japanese Cedar is the dominant species among plantations in Japan. We measured organic carbon and nitrogen content as well as changes in carbon (δ13C) and nitrogen (δ15N) stable isotope composition in a steep west facing slope under heavy precipitation (~2600 mm/a) and heavy snowfall (~3 to 4 m/a). The accumulation of Ctotal and Ntotal at the bottom of the slopes was remarkably higher at the slash and burned site than in the control forest site. After slash and burn δ15N isotopes in the slope in general became significantly lighter than in the control forest while the δ13C did not show any significant difference between the two sites except at the bottom of the slopes where δ13C was heavier in the forest. The results show that Ctotal and Ntotal values as well as the isotopes ratios of C and N change with decreasing elevation in the forest as well as in the burned site being consistent with leaching and erosion. The changes in soil nitrogen and carbon isotopes at the bottom of the slope appear to be related to the transport of material with different isotopic composition from the upper slope. The effect of the low severity fire (as part of the slash and burn practice) on soil organic carbon and nitrogen movement was enhanced by the steepness of the slopes and the high precipitation of Shonai region. 展开更多
关键词 High Precipitation Japanese cedar Forest SOIL LOW SEVERITY FIRE Stable Isotopes STEEP Slopes
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MANET中基于蚁群的网络核心提取分布路由协议 被引量:1
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作者 何炎祥 文卫东 +1 位作者 金辉 刘浩文 《计算机工程》 CAS CSCD 北大核心 2006年第14期83-84,106,共3页
提出了一个用于移动Ad Hoc网络(MANET)的基于蚁群的核心提取分布路由协议——Ant-CEDAR,该协议使用类似蚁群的移动代理获得高效的路由,从而可加强核心提取分布Ad Hoc路由算法(CEDAR)。对Ant-CEDAR协议进行了模拟实验,实验数据表明该协... 提出了一个用于移动Ad Hoc网络(MANET)的基于蚁群的核心提取分布路由协议——Ant-CEDAR,该协议使用类似蚁群的移动代理获得高效的路由,从而可加强核心提取分布Ad Hoc路由算法(CEDAR)。对Ant-CEDAR协议进行了模拟实验,实验数据表明该协议具有高效性和低耗性。 展开更多
关键词 MANET 蚁群 cedar
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