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A new methodology is proposed in this paper to predict the lowest power consumption for a double-tube-socket (DTS) pneumatic conveying system. This methodology is established on both experimental work and numerical simulation. After parametric studies by numerical simulation, the desired conveying cases which have the lowest power consumption were obtained. Finally those cases were carried out in our experimental system. The measured power consumption was close to that predicted. In this paper the experimental work is discussed and the numerical simulation introduced. (c) 2010 Elsevier B.V. All rights reserved.

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胺及其衍生物是很多重要生物活性分子的结构单元,是合成天然产物和手性药物的重要中间体。 直接还原胺化由于其合成步骤简单而成为制备二级胺和三级胺的简便方法。为了发展一种较为简便的直接还原胺化反应,我们把研究的重点放在开发一种简便实用的有机小分子催化方法上。由文献调研可知,现已报道的直接还原胺化方法大多是催化醛或酮与一级胺或者脂肪二级胺的直接还原胺化,而醛或酮与芳香二级胺的直接还原胺化却尚无报道。在本文中,我们发现用简单的四甲基乙二胺(TEMED)在室温下以二氯甲烷为溶剂即可催化三氯氢硅对酮和芳香二级胺之间的直接还原胺化反应,并取得了高达92%的收率。该反应条件温和,底物普适性广,各种类型的酮均可以与芳香二级胺进行直接还原胺化,并且得到比较满意的收率。 同时,我们从手性Sulfoximine出发,设计和合成了一系列的Sulfoximine类新衍生物,并将其应用于间接还原胺化反应中。遗憾的是我们并没有得到预期的不对称催化效果。 Amines and their derivatives are basic structural motifs in natural products and pharmaceuticals and highly versatile building blocks for various organic substrates. Direct reductive amination (DRA) is a convenient method for the preparation of secondary and tertiary amines owing to its operational simplicity. In an effort to develop a simple and convenient procedure for direct reductive amination reaction, we focused our study on search for a mild and efficient organocatalytic system. In the literature, there are many reports concerning DRA between aldehydes or ketones and either primary amines or secondary aliphatic amines. But there are no reports concerning DRA between aldehydes or ketones and secondary aromatic amines. In this study, we have developed a highly practical method for the synthesis of tertiary amines by the direct reductive amination of ketones and secondary aromatic amines with tetramethylethylenediamine (TEMED) as the catalyst using HSiCl3 as the reducing agent in dichloromethane (affording up to 92% yield). This method can be carried out under mild conditions and is compatible with many functional groups. A variety of ketones were efficiently aminated with secondary aromatic amines to afford the corresponding amines in good to excellent yields. Starting from chiral sulfoximine, we designed and synthesized a series of new sulfoximine derivatives and tested their efficiencies as asymmetric organocatalysts for the reduction of imines, which, unfortunately, only exhibited low catalytic activity and enantioselectivity.

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随着工业化的发展,大气中二氧化碳的浓度(CO2)预测从现在的平均350μmol·mol-1升高到2030年的570μmol·mol-1,其增温作用将持续多个世纪。植被在大气二氧化碳减排以及调控区域水热状况过程中起重要作用,而其机理过程目前十分不清楚。本实验应用自控、封闭、独立生长室,研究了CO2浓度和温度升高对红桦根、茎、叶和枝可溶性蛋白含量和分配的影响,从蛋白水平上来解释川西亚地区的建群种-红桦对CO2升高和温度升高及其交互作用的响应规律,为全球气候变暖川西亚高山的植被保护和恢复提供理论依据。研究结果表明: 1. CO2浓度升高增加了可溶性蛋白的总量,改变了可溶性蛋白分配模式,即,可溶性蛋白分配到根的比例增加,分配到茎、枝、叶的比例减少。可能意味:在CO2浓度升高条件下,红桦根系的生长和营养物质吸收功能将会增强。 2. CO2浓度升高增加了根和茎的清蛋白含量,降低了叶片的清蛋白含量,叶片的球蛋白含量、醇溶蛋白含量和谷蛋白含量均增加。表明CO2浓度升高增加了清蛋白在根中积累,球蛋白、醇溶蛋白和谷蛋白大量在叶片中积累;前人研究所指出的CO2浓度升高使植物叶片可溶性蛋白的含量降低可能仅仅是由于清蛋白含量的降低造成的。 3. 温度升高使红桦幼苗整株所含可溶性蛋白总量增加,但可溶性蛋白总量的分配因红桦幼苗器官的不同而异。温度升高下根、茎、叶和枝的分配量分别占总可溶性蛋白的27.74%、35.57%、23.00%、13.68%,即茎>根>叶>枝。对照的根茎叶枝的分配量分别占总可溶性蛋白的21.01%、41.41%、23.08%、14.50%,即茎>叶>根>枝。表明温度升高使可溶性蛋白分配到根的比例增加,有利于根的可溶性蛋白的积累,增强了根吸收水分和矿质营养的能力,从而有利于根系的生长。 4. 温度升高处理下清蛋白和球蛋白在根中含量升高,在茎、叶和枝中含量下降,但没有达到显著水平;醇溶蛋白在根和叶中含量显著增加;谷蛋白在茎中的含量显著降低。表明温度升高增加清蛋白和球蛋白在红桦幼苗根部的积累,也有利于根和叶醇溶蛋白的积累,但不利于谷蛋白在茎的积累;温度升高条件下叶片可溶性蛋白升高是醇溶蛋白在叶片中积累的结果。 5. CO2浓度和温度同时升高条件下红桦幼苗的可溶性蛋白总量增加很少,只有分配到茎的可溶性蛋白比例增加,并且对可溶性蛋白分配规律没有影响。CO2和温度同时升高下红桦幼苗枝的可溶性蛋白含量的降低是可溶性蛋白总量的降低而不是碳水化合物稀释的结果,并且CO2和温度同时升高对红桦幼苗的生长没有明显的促进作用。 6. CO2和温度同时升高处理对可溶性蛋白含量有显著影响。清蛋白含量在根、茎、叶和枝中均降低,球蛋白含量在根中显著降低,醇溶蛋白含量在根、茎、叶和枝中均降低,谷蛋白含量在根中显著降低。表明CO2浓度和温度同时升高对根的影响显著,即降低了根的可溶性蛋白含量,可能导致根的吸收能力下降。 7. 因此,CO2和温度同时升高对可溶性蛋白影响不能简单地通过CO2和温度单因子影响机理来解释。 It is well known that atmospheric CO2 concentration and temperature are increasing as a consequence of human activities. Atmospheric CO2 concentration are predicted to increase from 350μmol·mol-1 now to 570μmol·mol-1 2030. And temperature will continue to increase for several centuries as a result of CO2 enrichment. Vegetation play a key role in reducing atmospheric CO2 and adapting and controlling warter and energy process in a certain region, while the underlying mechanism are not clear, yet. Betula albo-sinensis, as the dominating tree species of subalpine dark coniferous forest in west Sichuan province, play an important role in determing structure and function of forest ecosystem. In our study, effects of elevated atmospheric CO2 concentration (ambient±350±25μmol·mol-1), increased temperature (ambient±2.0±0.5℃) and their combination on contents and allocation of soluble protein were studied in independent and enclosed-top chamber system under high-frigid conditions. Chambers with ambient CO2 concentration and temperature are taken as control. The results are as the following, 1) Elevated atmospheric CO2 increased the accumulation of total weight of soluble protein in whole plant and changed allocation of soluble protein in red birch by increasing its allocation to roots and reducing its allocation to stem. This caused much more accumulation of soluble protein in roots which might help to prompt growth, development and nutrient absorption ability of roots. 2) Treatment EC increased content of albumin in roots and stems, reduced the content of albumin in leaves, and increased the content of globulin, promalin and glutenin in leaves. That is to say EC increased the accumulation of albumin in roots and accumulation of globulin, promalin and glutenin in leaves. The reduced soluble protein contents in plant leaves by EC, as reported by former researchers, are mainly resulted from the reduced content of albumin in leaves. 3) Elevated temperature increased the total of soluble proteins, but its allocation was dependent on organs. In treatment ET, roots, stems, leaves and branches take 27.74%, 35.57%, 23.00% and 13.68% of total weight of soluble protein. In treatment CK, roots, stems, leaves and branches take 21.01%, 41.41%, 23.08% and 14.50%. Elevated temperature changed allocation of soluble proteins in that it stimulated soluble proteins accumulation in roots and improved the uptake of water in roots. 4) Treatment ET increased the content of albumin and globulin in roots, and reduced the content of albumin and globulin in stems, leaves and branches. The content of promalin in roots and leaves was increased significantly, and the content of glutenin in stems was reduced significant. This suggested that ET stimulated the accumulation of albumin and globulin in roots and accumulation of promalin in leaves and roots; that treatment ET increased content of soluble protein in leaves was mainly resulted from the increased promalin content in leaves. 5) Regarding treatment ETC, the total of weight of soluble proteins increased, but not significantly; but increased in stems. So the combination of elevated atmospheric CO2 and temperature had not changed the allocation of soluble proteins in red birch seedling and reduced soluble proteins in branches were not the result of increased carbohydrate. 6) Treatment ETC reduced the content of albumin and promalin in roots, stems, leaves and branches, reduced the content of globulin and glutenin in roots significantly. That is to say elevated atmospheric CO2 and temperature reduced the content of soluble proteins in roots significantly which might help to prompt growth, development and nutrient absorption ability of roots. 7) The effects of elevated atmospheric CO2 and temperature on soluble protein cannot be simply interpreted through their mechanism that obtained when they were imposed on plant separately.

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黄龙世界自然遗产地岷江冷杉林(Abies faxoniana)生境类型多样,群落结构复杂,群落植物种类组成多样性丰富。揭示不同生境的生物多样性及其差异是认识生物多样性格局、形成及维持机制的前提和进行多样性保育的基础。本文采用样方法对黄龙钙化滩生境、阴坡非钙化生境及半阳坡非钙化生境的岷江冷杉原始林植物群落结构及植物多样性进行了研究。结果表明: 黄龙岷江冷杉林具有明显的复层异龄结构,垂直结构明显,乔木、灌木、草本、苔藓层次分明。共发现高等植物386 种,其中维管植物46 科103 属163 种,苔藓植38 科83 属物223 种。各层片结构及物种组成如下: (1)钙化滩生境、阴坡非钙化生境、半阳坡非钙化生境分别发现乔木18 种、13种、8 种。乔木层均可分为两个亚层,第一亚层优势种均为岷江冷杉,第二亚层主要为岷江冷杉异龄树或其它大高位芽物种。钙化滩生境第一亚层除优势种岷江冷杉外混生有巴山冷杉(Abies fargesii)、粗枝云杉(Picea asperata)以及阔叶树种白桦(Betula platyphylla)等,第二亚层主要为岷江冷杉异龄树;阴坡非钙化生境第一亚层除优势种岷江冷杉外间有巴山冷杉和白桦,第二亚层物种主要为川滇长尾槭(Acer caudatum var. prattii);半阳坡非钙化生境第一亚层除优势种岷江冷杉外混生有巴山冷杉,第二亚层主要为岷江冷杉异龄树。依乔木层优势种的差异,钙化滩生境及半阳坡非钙化生境为岷江冷杉纯林,阴坡非钙化生境为岷江冷杉-川滇长尾槭混交林。不同生境乔木层郁闭度、乔木密度、树高结构、直径结构均存在差异。 (2)钙化滩生境发现灌木41 种,平均盖度为18.49±1.72(%),平均高度为52.12±4.45(cm),优势种为直穗小檗(Berberis dasystachya);阴坡非钙化生境发现灌木30 种,平均盖度为29.33±2.56 (%),平均高度为119.55±8.01 (cm),优势种为箭竹 (Fargesia spathacea) 、唐古特忍冬(Lonicera tangutica) 和袋花忍冬(Lonicera saccata);半阳坡非钙化生境发现灌木29 种,平均盖度为31.35±1.93 (%),平均高度为107.55±4.24 (cm),优势种为箭竹(Fargesia spathacea)。不同生境灌木层结构和物种组成多样性差异显著,钙化滩生境的灌木盖度、高度总体上较非钙化的坡地生境低, 钙化滩生境灌木以小型叶的落叶灌木为主,沟两侧非钙化的坡地生境上则发育了丰富箭竹。 (3)钙化滩生境发现草本46 种,平均盖度为7.18±0.79 (%),平均高度为5.04±0.26(cm),以山酢浆草(Oxalis griffithii)为优势种;阴坡非钙化生境发现草本物种71 种,平均盖度达29.04±2.31(%),平均高度为9.08±0.52(cm),以钝叶楼梯草(Elatostema obtusum)、山酢浆草为优势种;半阳坡非钙化生境草本物种50 种,平均盖度为以8.79±0.82(%),平均高度为7.67±0.43 (cm),以扇叶铁线蕨(Adiantum flabellulatum)、双花堇菜(Viola biflora)、华中蛾眉蕨(Lunathyrium shennongense)、山酢浆草为优势种。阴坡非钙化生境草本层片发育良好,多样性最为丰富,盖度和物种丰富度均显著高于钙化滩生境和半阳坡非钙化生境。 (4)钙化滩生境发现苔藓物种140 种,平均盖度达84.25±1.30 (%),以仰叶星塔藓(Hylocomiastrum umbratum) 等大型藓类为优势种;阴坡非钙化生境发现苔藓物种115 种,平均盖度为79.29±1.64 (%),以刺叶提灯藓(Mnium spinosum)、大羽藓(Thuidium cymbifolium)、毛尖燕尾藓(Bryhnia trichomitra)等个体较小的物种为优势种;半阳坡非钙化生境发现苔藓物种91 种,平均盖度为60.64±1.93 (%),也以刺叶提灯藓为优势种。 (5)钙化滩生境、阴坡非钙化生境、半阳坡非钙化生境的物种数分别为234 种、221 种、175 种。乔木层的Shannon-Wiener 指数分别为0.75 ±0.12、1.87±0.12、1.78±0.07(灌木层,0.44±0.08、1.71± 0.15、2.49±0.06;草本层,0.33±0.13、1.31±0.15 、2.15±0.08; 苔藓层1.30±0.11、2.08±0.04、1.73±0.11,);Pielou 均匀度指数分别为0.45±0.05、0.29±0.06、0.28±0.08(灌木层,0.75±0.03、0.68±0.05、0.52±0.06;草本层,0.68±0.02、0.77±0.02、0.74±0.02;苔藓层,0.40±0.03、0.63±0.02、0.52±0.03);Simpson's 优势度指数分别为0.63±0.06、0.78±0.04、0.83±0.07(灌木层,0.21±0.03、0.28±0.05、0.45±0.06;草本层,0.25±0.02、0.12±0.01、0.17±0.01;苔藓层,0.45±0.04、0.18±0.01、0.31±0.04)。三种生境间乔木层、草本层的Sorenson 群落相似性系数较低, 灌木层、苔藓层的的Sorenson 群落相似性系数较高。 综上所述,黄龙岷江冷杉林的群落结构、植物多样性在三种生境间存在差异性,这将意味着我们在进行黄龙世界自然遗产地的森林经营管理时要较多地关注岷江冷山林群落在不同生境中的差异性。 There were multiplex habitat types, complicated community structure and abundant species composition in the Huanglong World Natural Heritage Site. Uncovering the differences of biodiversity among different habitats was a precondition to understand the distribution, formation and sustaining mechanism of the biodiversity, and the foundation of biodiversity conservation. In the present study, using plenty of quadrants, we investigated the community structure and the biodiversity of the primitive Abies faxoniana forest in different habitats (travertine bottomland, semi-sunny-slope non-calcified habitat and shady-slope non-calcified habitat) in the Huanglong World Natural Heritage Site. The main results are as follows: All the primitive Abies faxoniana forests in the three habitats were uneven-aged with obvious vertical structure including tree layer, shrub layer, herb layer and bryophyte layer. A total of 386 higher plants including 163 vascular plant species (103 generic, 46 families) and 223 bryophyte species (83 generic, 38 families) were investigated. The structure and species composition of each layer are as follows: (1) There were 18, 13 and 8 tree species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. The tree layers in all habitats can be divided into two clear sub-layers. The upper tree layers were dominated by Abies faxoniana, and the lower tree layers were dominated by uneven-aged Abies faxoniana or other phanerophytes species. There were Abies fargesii , Picea asperata and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in travertine bottomland, and the lower tree layers were dominated by uneven-aged Abies faxoniana; There were Abies fargesii and Betula platyphylla besides the dominated species (Abies faxoniana) in the upper tree layer in shady-slope non-calcified habitat, and the lower tree layers were dominated by Acer caudatum var. prattii; There was Abies fargesii besides the dominated species (Abies faxoniana) in the upper tree layer semi-sunny-slope non-calcified habitat, and the lower tree layers were dominated by uneven-aged Abies faxoniana. According to composition percentage of dominate species in tree layer, both the forest in travertine bottomland and in semi-sunny-slope non-calcified habitat could be ranked as pure forest, and the forest in shady-slope non-calcified habitat could be ranked as mingled forest. There were significant differences in crown density, plant density, height structure and diameter structure among the three habitats. (2) A total of 41 shrub species (average coverage 18.49±1.72%; average height 52.12±4.45 ㎝)were found in travertine bottomland, and the dominate species was Berberis dasystachya; A total of 30 shrub species (average coverage 29.33±2.56 %;average height 119.55±8.01 ㎝)were found in shady-slope non-calcified habitat, and the dominate species was Fargesia spathacea, Lonicera tangutica and Lonicera saccata. A total of 29 shrub species (average coverage 31.35±1.93%; average height 107.55±4.24 ㎝) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Fargesia spathacea. There were significant differences in structure and species diversity of the shrub layers among the three habitats. The coverage and height of shrub had lower value in travertine bottomland than in two non-calcified habitats. Moreover, travertine bottomland was dominated by deciduous shrub species with microphyll and non-calcified habitats developed abundant Fargesia spathacea species. (3) A total of 46 herb species (average coverage 7.18±0.79%;average height 5.04±0.26 ㎝)were found in travertine bottomland, and the dominate species was Oxalis griffithii; A total of 71 herb species (average coverage 29.04±2.31%;average height 9.08±0.52 ㎝)were found in shady-slope non-calcified habitat, and the dominate species was Elatostema obtusum and Oxalis griffithii. A total of 50 herb species (average coverage 8.79±0.82%;average height 7.67±0.43 ㎝) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Adiantum flabellulatum, Viola biflora, Lunathyrium shennongense and Oxalis griffithii. Herb layers developed well in shady-slope non-calcified habitat and had the higher species richness and coverage than travertine bottomland and semi-sunny-slope non-calcified habitat. (4) A total of 140 bryophyte species (average coverage 84.25±1.30%)were found in travertine bottomland, and the dominate species was big bryophyte species such as Hylocomiastrum umbratum and so on; A total of 115 bryophyte species (average coverage 79.29±1.64%)were found in shady-slope non-calcified habitat, and the dominate species was small bryophyte species such as Mnium spinosum, Thuidium cymbifolium, Bryhnia trichomitra and so on. A total of 91 bryophyte species (average coverage 60.64±1.93%) were found in semi-sunny-slope non-calcified habitat, and the dominate species was Mnium spinosum. (5) There were 234, 221 and 175 plant species in travertine bottomland, shady-slope non-calcified habitat and semi-sunny-slope non-calcified habitat, respectively. Shannon-Wiener index of the tree layer was 0.75 ±0.12, 1.87±0.12 and 1.78±0.07 (the shrub layer, 0.44±0.08, 1.71± 0.15 and 2.49±0.06; the herb layer, 0.33±0.13, 1.31±0.15 and 2.15±0.08; the bryophyte layer, 1.30±0.11, 2.08±0.04 and 1.73±0.11.) for the three habitats, respectively; Pielou index of the tree layer was 0.45±0.05, 0.29±0.06 and 0.28±0.08 (the shrub layer, 0.75±0.03, 0.68±0.05 and 0.52±0.06; the herb layer, 0.68±0.02, 0.77±0.02 and 0.74±0.02; the bryophyte layer, 0.40±0.03, 0.63±0.02 and 0.52±0.03.) for the three habitats, respectively. Simpson's index of the tree layer was 0.63±0.06, 0.78±0.04 and 0.83±0.07 (the shrub layer, 0.21±0.03、0.28±0.05、0.45±0.06; the herb layer, 0.25±0.02, 0.12±0.01 and 0.17±0.01; the bryophyte layer, 0.45±0.04, 0.18±0.01 and 0.31±0.04.) for the three habitats, respectively. There were low Sorenson index both in the tree layer and in the herb layer among the three habitats, whereas, high Sorenson index occurred both in the shrub layer and in the bryophyte layer. To sum up, there were differences both in community structure and plant diversity among the three different habitats, which means that we should pay more attention to habitats heterogeneities of the primitive Abies faxoniana forest when we take action to manage the forest in the Huanglong World Natural Heritage Site.

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禾谷孢囊线虫(Heterodera avenae)是严重危害禾谷类作物的病原线虫之一,它广泛分布于澳大利亚、欧洲、北美、印度和中国等世界主要小麦产区,使作物严重减产,造成巨大的经济损失。目前最有效的防治措施之一是将外源抗性基因导入栽培小麦(Triticum aestivum L.),培育抗禾谷孢囊线虫的新品种。但迄今为止抗禾谷孢囊线虫基因克隆研究的相关报道却很少。 本实验根据此前从抗禾谷孢囊线虫材料E-10扩增得到的与来自节节麦(Aegilops tauschii)的抗禾谷孢囊线虫基因Cre3高度同源的序列Rccn4,设计出三条嵌套引物,采用SON-PCR(single oligonucleotide nested PCR)方法,从E-10基因组DNA中得到一个长为1264 bp的扩增产物(命名为Rccn-L),测序比对结果显示,这一序列将Rccn4的3’端延伸了1209 bp,与抗禾谷孢囊线虫Cre3基因核苷酸同源性为86﹪,核苷酸编码区长1026 bp,含一个不完整的开放阅读框,一个终止密码子,没有起始密码子和内含子结构,编码一个342个氨基酸残基的蛋白质。该蛋白质等电点为5.19,分子量为38112.6Da。从序列的第113位开始到第332位是NBS-LRR类抗病性基因LRR区,呈现XXLXXLXXL重复。LRR编码区内亮氨酸残基的含量达17﹪,与抗禾谷孢囊线虫Cre3基因LRR编码区的核苷酸和氨基酸同源性分别为89﹪和78﹪。本实验首次将SON-PCR成功地运用于植物基因克隆,为植物基因克隆提供了又一有效方法。 此外,还根据Cre3基因及其他的NBS-LRR类植物抗性基因的NBS和LRR区保守序列设计了两对特异性引物,从禾谷孢囊线虫抗性材料易变山羊草基因组DNA中扩增到两个相应的目标条带。测序分析结果表明,它们的长度分别为532bp和1175bp,构成了一个有32bp的共同序列的NBS-LRR编码区。其序列总长为1675bp(命名为RCCN),含有一个不完整的开放阅读框,没有起始密码子、终止密码子和内含子结构。其中编码序列为1673bp,可编码一个557个氨基酸的蛋白质,等电点(pI)为5.39,分子量为63537.5Da。与Cre3的核苷酸和氨基酸同源性分别为87.8﹪和77﹪。RCCN氨基酸序列中含有已知抗病基因NBS区域的几个保守模体:kinase2区的ILDD、kinase3的(ⅰ)ESKILVTTRSK,(ⅱ)KGSPLAARTVGG,(ⅲ)RRCFAYCS及EGF。RCCN NBS区与Cre3 NBS区的核苷酸和氨基酸的同源性分别为96.4﹪和94﹪。从氨基酸序列的274位到548位为LRR保守区,呈现不规则的aXXLXXLXXL(其中a代表I,V,L,F或M)重复,其中亮氨酸的含量为15.6﹪。该区域与Cre3的LRR区的核苷酸和氨基酸同源性分别为80.8﹪和74﹪。推测该序列可能为一个抗禾谷孢囊线虫的新基因。 本文对抗禾谷孢囊线虫基因的克隆研究,为进一步克隆基因全序列,探索其结构与功能,和研究该基因表达与调控提供了关键信息。同时也为通过基因工程途径将抗性基因向优良小麦品种高效、定向转移,最终培育出小麦抗禾谷孢囊线虫新品种奠定了基础。 Cereal cyst nematode (CCN) is a damaging pathogen of broad acre cereal crops in Australia, Europe, North America, India and China. It affects wheat, barley, oat and triticale and causes yield loss of up to 80%. At present, Transferring resistance genes against CCN into wheat cultivars and breeding varieties are considered one of the most effective methods for controlling the CCN. However, there are very limited reports concerning the cloning studies of resistance genes against the cereal cyst nematode. According to the sequence of Rccn4 which had high similarity to the nucleotide binding site (NBS) coding region of cereal cyst nematode resistance gene, Cre3, We designed three 3’ nested primers. Using single oligonucleotide nested PCR (SON-PCR) we successfully amplified one band, Rccn-L, of 1264bp from E-10 which is the wheat-Ae.variabilis translocation line containing the cereal cyst nematode resistance gene of Ae.variabilis. We found that this band of interesting is the 3’ flanking sequence of 1209bp in size of Rccn4. The coding region was 1026bp, which contained an incomplete open reading frame and a terminator codon, without initiation codon and intron, encoding a peptide of 342 amino acid residues, and shared 86﹪nucleotide sequence identity with Cre3. This peptide had a conserved LRR domain, containing the imperfect repeats,XXLXXLXXL, which contains 17﹪ leucine residues and shares, respectively, 89﹪ nucleotide sequence and 78﹪ amino acid sequence identity with the LRR sequence of Cre3 locus. This research firstly used SON-PCR in the research of plant genome successfully, which indicated that SON-PCR is another method of cloning plant gene. At the same time, According to the conversed motif of NBS and LRR region of cereal cyst nematode resistance gene Cre3 from wild wheat (Triticum tauschlii L.) and the known NBS-LRR group resistance genes, we designed two pairs of specific primers for NBS and LRR region respectively. One band of approximately 530bp was amplified using the specific primers for conversed NBS region and one band of approximately 1200bp was amplified with the specific primers for conversed LRR region. After sequencing, we found that these two sequences included 32bp common nucleotide sequence and have 1675 bp in total, which was registered as RCCN in the Genbank. RCCN contained a NBS-LRR domain and an incomplete open reading frame without initiation codon, terminator codon and inxon. Its exon encodes a peptide of 557 amino acid residues. The molecular weight of the protein from the amino acid was 63.537 KDa. The amino acid sequence of RCCN contained conserved motif: ILDD, ESKILVTTRSK, KGSPLAARTVGG, RRCFAYCS, EGF,LRR. RCCN shares 87.8﹪ nucleotide sequence and 77﹪ amino acid sequence identity with cereal cyst nematode gene Cre3. It might be a novel cereal cyst nematode resistance gene. These research results of cloning the resistance genes against cereal cyst nematode bring a great promise for transferring resistance genes into wheat cultivars and breeding new wheat varieties against cereal cyst nematode by gene engineering. And these results also lay the hard foundation for the expressing researches of these genes.

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This paper introduced a real-time vacuum monitor system based on multilayer Web architecture for HIRFL-CSR(Heavy Ion Research Facility of Lanzhou & Cooler Storage Ring) project in Lanzhou.It combined with COM/DCOM to develop the application layer,and developed the web layer with ActiveX and Ajax technology.It provided a facility and efficiency method for real-time control.The application shows that this system runs stably and accurately.中文文摘:简要介绍了国家"九五"重大科学工程——兰州重离子加速器冷却储存环(HIRFL-CSR)真空监控系统的总体结构,分析了在Web构架下,基于分布式内存数据库的多层真空监控系统的实现方法。采用分布式内存数据库,解决了基于Web构架的分布式实时应用环境下对系统和网络资源的消耗问题。在软件控制方面采用了统一调度,既简化了软件实现过程,又提高了系统的安全性、高效性和易维护性。该系统已成功运行。

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描述了硫酸铵溶液中铀矿坑水样品中铀的电沉积层特性。电沉积液为10ml0.8M的硫酸铵溶液,电流密度0.6A/cm2,pH值为2.5,电镀1h。电沉积经化学分离后的水样品和电沉积的纯硝酸铀酰样品进行了比较,并对二者分别做了红外(IR)光谱、扫描电镜(SEM)、元素分析以及α能谱测量。IR谱上铀酰离子的反对称伸缩振动峰在887cm-1附近,使电沉积在不锈钢片上的铀主要以铀酰离子水合物的形式存在,有一部分NH4+以NH3的形式替代水合物中的水,使电沉积层中铀的化合物形式为UO2(OH)2.xNH3.yH2O或者UO2(OH)2-x.(ONH4)x.yH2O,铀酰离子通过链的形式形成聚合结构。SEM照片显示电沉积层均匀,没堆积成团现象出现。α谱表明电沉积层中铀的同位素主要是238U和234U,相应的α能量峰4198和4773keV很显著,没其它峰的干扰。

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HIRFL-CSR调试过程中,利用频谱分析仪实时监测束流,根据其上测的数据进行相关参数调整,改善束流的品质。本文对分析仪上观测到的现象—束流的中心频率发生突变进行了研究,主要就电子束的高压不稳定性和中性化因子的突变做了理论分析,并进行了相关的模拟计算,根据模拟结果初步断定该现象的出现由电子束的中性化因子导致。

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本试验利用电子辐照PVA/CMC共混水凝胶,通过外观透明度、凝胶分数、溶胀度和红外光谱分析,研究了样品中结构的变化与外观透明度、凝胶分数和溶胀度的关系,以及辐照剂量对样品中结构和性能的影响。结果表明,不同比例的PVA与相同比例的CMC组成的共混水凝胶,经电子辐照后呈现不同的宏观特性。辐照样品萃取后得到的凝胶比萃取前的混合凝胶拥有更强的吸水性,表明辐照PVA/CMC共混凝胶形成了网状结构凝胶。几种竞争反应导致不同辐照剂量下混合凝胶中凝胶含量随PVA含量的变化变得复杂。辐照后样品的红外光谱分析显示,辐照使凝胶中部分仲醇中C上链接的H原子被取代而转变为叔醇,从而产生交联。