943 resultados para 20-MUC 5


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微生物修复是石油污染土壤修复的主要方法之一,但是对修复过程中微生物的检测却是其主要限制因素,传统的检测方法存在很大的局限性,而荧光原位杂交技术结合了分子生物学的精确性和显微镜的可视化信息,可较为精确快速的对微生物进行定性和定量测定。 实验中利用辽河油田污染土壤中筛选纯化的高效石油降解菌,以原油为碳源,考察不同菌株处理后的去除率变化。发现有8株菌:B101、B381、B0502、B25 、B64、B2001、B2003、B18,在14 d内对石油的降解率都在20%以上,且族组分分析结果显示,被降解部分主要是烷烃和芳烃。经鉴定,此8株菌均为杆菌。 同时,对5株石油降解菌标准菌株(铜绿假单胞菌、巨大芽孢杆菌、枯草芽孢杆菌、苏云金芽孢杆菌和地衣芽孢杆菌)在基因库中比对,核苷酸同源性显示其相似性均在98%以上,因此针对其16S rRNA设计寡核苷酸探针。 将上述5种探针应用于荧光原位杂交实验,分别作用于8株降解菌和5株标准菌株,得出5种探针均符合特异性标准,仅地衣芽孢杆菌探针与B381之间有特异性荧光反应。添加B381(地衣芽孢杆菌)于泥浆反应器中降解石油烃。鉴于石油污染土壤的复杂组成,检测泥浆反应器中地衣芽孢杆菌的FISH条件优化结果为:样品固定时间17 h,杂交温度46 ℃,杂交时间3 h,杂交液中去离子甲酰胺浓度35%,冲洗缓冲液中与去离子甲酰胺对应的NaCl的浓度88 mmol∙L-1。运用上述FISH技术监测生物泥浆反应器中地衣芽孢杆菌量的变化,得出地衣芽孢杆菌的浓度在第5天达到最大,同时对泥浆反应器中去除率进行测定,前5天菌对原油的去除速率也最高,前8 d是石油烃被去除的主要作用阶段。微生物的数量变化和原油的去除率进行比较,两者的变化情况符合微生物降解石油的趋势,为监测含油污泥中微生物的变化提供了一种可行的技术。

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多环芳烃(PAHs)作为一种普遍的环境污染物已开始在一些地区的土壤中高度富集,特别是在与石油、天然气和木材防腐有关的工厂所在地尤为如此。它们作为优先环境污染物而引起人们的关注是因为其中的许多种类已被证明是致癌物、致畸物和诱变剂。多环芳烃在土壤中具有相对稳定性,因此它比一般有机污染物更难降解。生物泥浆反应器已被国外证明是最有效的有机污染土壤清洁方法。本项研究利用自设计的国内第一个生物泥浆反应器对污染土壤中的多环芳烃在生物泥浆反应器中的降解条件进行研究,并优化其运行工艺参数。本研究采用三环的菲和四环的芘作为多环芳烃供试化学品。处理装置为小型的生物泥浆反应器(15L/个)。反应器配备搅拌、通气和温度控制装置,在好氧条件下进行。本项研究设计了七组不同的处理条件:不同的起始浓度(PAHs)、不同的温度(10℃,20℃,30℃)、不同的微生物接种量(5%,10%,15%,20%[W/W])、不同的表面活性剂浓度(Tween-80),研究了生物泥浆反应器在不同处理条件下对多环芳烃污染土壤的净化效果。研究结果表明,温度变化、表面活性剂浓度、接种量均对菲和芘的生物降解有明显影响。菲(3环)在生物泥浆反应器中其浓度很快降低,在360小时内去除率达97%。芘(4环)在实验浓度下下降相对较慢,360小时最高去除率也可达87%以上,平均去除率为50%以上,去除效果明显。在本研究中,多环芳烃在反应器中生物降解的最佳条件是20℃-30℃、水土比为2/1、接种量为5%、添加Tween-80的浓度为10mg/kg。本项研究首次将多环芳烃的生物泥浆反应器降解过程分为两个阶段,第一阶段是多环芳烃的快速降解阶段;第二阶段是降解停滞阶段。指出共代谢底物应在第二阶段投加为宜;研究了影响菲与芘生物半减期的因素;指出了初始浓度对菲与芘生物降解效果的不同影响;对泥浆反应器处理PAHs的运行条件进行了较为全面的研究,为这一技术的广泛应用奠定了基础。

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本文研究了两种小麦品种在不同土壤(处理)中其根际土壤中pH、磷酸酶活性、全磷以及速效磷含量的变化,通过实验发现,小麦的根毛特性是有一定差异的,在本实验中,石冬5号小麦的根毛长度是1.02毫米,而Sleipner小麦的为0.49毫米,前者是后者的2倍。石冬5号由于有较长的根毛,因此,和Sleipner小麦相比,其每毫米根引起的根表面积的增加量是1.92倍,而Sleipner则是0.68倍。石冬5号小麦的每毫米根所接触的根际土壤的体积是4.55立方毫米,是Sleipner小麦的2.6倍。石冬5号在速效磷含量较高的土壤中吸收的磷的量比Sleipner小麦多1%;在速效磷含量中等的土壤中比Sleipner小麦多12.9%;在速效磷含量较低的土壤比Sleipner小麦多20-30%。两种小麦根际土壤中全磷含量的变化不显著。和未种植小麦的处理相比,所有小麦品种的根际土壤中磷酸酶活性都有了显著的变化。从根际外5毫米到根际内0.2毫米,磷酸酶活性逐渐升高。但是在同一土壤中,两种小麦根际土壤中磷酸酶活性的变化没有显著的差异。在本实验中,由于对影响土壤pH值变化的外部因素进行了控制,所以两种小麦根际土壤中pH值的变化没有显著差异。本文的目的是植物诱导的根际土壤pH的变化对土壤中磷的生物有效性的影响。通过实验我们得到了以下的结果:靠近要面的根际土壤的pH变化不同于远离根面的土壤。根际土壤pH的变化范围一般为2-3毫米。随着离根面距离的增加,pH的变化逐淅减小。根际土壤pH的变化与植物的种类、土壤中施入的氮肥的形态有关。在相同的外部条件下,油菜根际土壤pH变化幅度和范围大于黑麦草。油菜和黑麦草施入氮肥后根际土壤pH的变化也不同,不论施入铵态氮还是硝态氮,油菜根际土壤的pH值都会发生下降,而施入铵态氮后,黑麦草根际土壤的pH会下降,施入硝态氮后根际土壤的pH会发生上升。油菜和黑麦草根际土壤中全磷、有机磷和无机磷的含量都有所下降。和黑麦草相比,油菜根际土壤磷含量下降的幅度和范围都较大。而且两种植物都能够利用根际土壤的有机磷。植物诱导的根际土壤的pH变化通过活化土壤磷来增加土壤中磷的和物有效性,具体表现在根际土壤的磷产生了亏缺,而且磷的亏缺是在一定范围内产生的。根际土壤的pH变化对于土壤中磷的生物有效性的影响和土壤的组成有关,在以钙磷为主的土壤中,根际土壤的pH的降低会增加土壤磷的有效性,这主要是通过促进土壤固相中的磷向土壤溶液释放,使土壤溶液中的磷维持在较高的浓度;而在以铁磷和铝磷为主的氧化土中,根际土壤的pH上升会增加土壤磷的有效性。

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辽东山区的天然次生林是辽宁的森林资源宝库和辽中城市群的天然屏障,在辽宁的经济建设和生态建设中发挥着不可替代的重要作用。辽东山区的天然次生林是原生植被阔叶红松林遭破坏后形成的次生群落,现大部分为低产、低质、低效的“三低”林分,因此天然次生林的恢复具有重要意义。本文对辽东天然次生林的演替动态、干扰对天然次生林的影响、恢复目标林分主要树种的生理生态学特性、恢复的生态过程及恢复技术等进行了系统研究,得出以下主要结论:(1)辽东山区的天然次生林,经聚类分析,分成四种主要类型即:柞木林、阔叶混交林、硬阔叶林和杨桦林。杨桦林在演替序列中的定位应属原生群落遭破坏后初级阶段即软阔混交林阶段。阔叶混交林主要是以锻属、榆属、械属、柞属等阔叶树种组成的群落,在演替序列中的定位应为软硬阔混交林阶段。硬阔叶林系指以辽东山区三大硬阔叶树种水曲柳、、黄菠萝、核桃揪等为主要树种组成的群落,在演替序列中的定位应为硬阔叶林阶段。柞木林是以栋属树种为优势树种的森林群落,它与阔叶红松林同时存在,是长白植物区系的一个亚顶极群落;(2)通过放牧对不同林分类型林木生长、森林环境以及部分生态功能的影响研究表明,天然次生林与其它林分类型比较,其抵御外来干扰的缓冲能力较强,具有一定稳定性。因此在天然次生林中可以适当放牧。科学地解决了辽东山区林牧矛盾问题。试验结果证明:不同采伐方式对天然次生林环境因子有明显影响。择伐是天然次生林较好的恢复途径,既不使森林环境发生大变化,同时择伐后还可以在林冠下引进针叶树,形成针阔混交林;(3)对天然次生林恢复所涉及到的主要树种红松、云杉、水曲柳、花曲柳、黄菠萝、蒙古柞、紫锻等进行了生理生态学特性与光环境关系的研究。红松是阳性树种,具有喜光的特性,但同时幼年又有一定的耐荫性。在透光10%条件下最大净光合速率为5.743μmofco2.m-2.s-1,全光条件下为8.233μmolco2.m-2.s-1。随树龄的增长趋于喜光。利用红松等针叶树的幼年耐荫特性,进行林冠下更新,使人工恢复阔叶红松林成为可能:在一定的光照范围内,水曲柳、花曲柳、黄菠萝、蒙古柞、紫锻这五种阔叶树的最大净光合速率随光照强度的增加而提高,在光照极弱的条件下生长不良,多数树种在透光70%条件下净光合速率最大;光饱和点、暗呼吸速率这五种阔叶树有所差异,蒙古柞和黄菠萝相对喜光,花曲柳和水曲柳居中,紫极相对耐荫;(4)天然次生林的人工恢复是多途径的。人工恢复阔叶红松林组成类型主要有:红松杂木林、红松花曲柳和蒙古柞林、红松水曲柳林、红松核桃揪林4种类型。各类型中红松重要值(相对密度+相对频度十相对优势度)均超过100;在天然次生林下人工栽植红松,经过20年大部分林分已形成三层垂直结构;人工恢复过程中林木的生长,上层保留木随着林冠的伐开,生长加快,迅速郁闭,这对林冠下栽植红松的成活有利。因光照条件改善,林下阔叶树生长迅速,并大量萌生新的个体。林冠下红松的初期高生长与全光条件下比较几乎无差异,巧年后开始低于全光条件下的生长。红松径生长,栽植10年后明显低于全光条件下的;(5)根据辽东山区天然次生林的形成、现状、在群落演替中的定位以及功能定位等确定辽东天然次生林主要恢复目标为:阔叶红松林、柞树林和阔叶混交林,面积比例分别以30%、65%和5%为宜;以对天然次生林现状、人为干扰对其影响、恢复目标群落所需要的引进种和天然次生林中的主要建群种的生理生态学特性以及人工诱导过程中,系统所发生的变化的研究为基础,并结合林龄、密度、立地条件等确定恢复途径,采取人工诱导、抚育间伐、人工营造针阔棍交林以及封育保护等技术措施完成恢复过程,达到恢复目的。天然林保护是我国正在实施的重大生态建设工程,辽宁省也出台了天然次生林禁止商业性采伐的措施,使辽东天然次生林的保护得到了政策保障。本文研究成果将为辽东天然次生林的保护、恢复以及可持续经营提供可靠的理论依据和技术支撑。

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本文结合野外调查和森林经营资料,以GIS为核心技术,综合空间分析与多种统计方法,研究了采伐干扰下白河林业局森林资源的动态变化,并使用FoREsTA严森林资源经营管理决策支持系统进行模拟,对多种采伐方案进行了系统的研究。该研究对指导整个长白山区的采伐经营,保护森林资源,实现森林生态系统科学经营与景观管理具有重要的理论意义。主要结论如下:①采伐活动在一定时间内改变植物种群的生态位,伐后10年7个树种的生态位宽度升高并逐渐高出原始林的生态位宽度。其生态位重叠从采伐后至伐后5年降低,以后逐渐升高,20年时与原始林基本相同;伐后灌木种群的生态位宽度与生态位重叠都增大,伐后巧年逐渐降低,伐后20年与原始林基本相同。②采伐强度影响植物群落的多样性,10%采伐强度采伐干扰的乔木的多样性伐后先降低再逐渐增加,20%和30%采伐强度采伐干扰的乔木的多样性随时间变化没有明显的规律;10%与20%采伐强度的灌木的多样性伐后先升高再降低,30%采伐强度的灌木多样性伐后先减少再增加;在所有采伐干扰中,草本层的多样性自伐后5年起逐渐升高,伐后20年,多样性基本趋于稳定。与原始林的多样性相比,10%的采伐强度可以增加乔木、灌木和草本的多样性,20%采伐强度增加了灌木的多样性。③经过13年经营,白河林业局森林林龄、单位蓄积和郁闭度较高等级的森林面积减少,较低等级的森林面积增加。林分质量下降。④经过13年,林业用地景观更加破碎,复杂程度降低,人类的干扰程度增强;基于景观划分的经营类型出现较大差异。⑤利用FoREsTA严决策支持系统进行采伐决策时,应该根据资源分布选择不同的采伐方案。从景观经营的角度,森林景观空间结构方案以及森林景观空间结构方案与实际木材采伐方案相组合后的方案更具有参考价值。

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<正>对采用热压烧结工艺(1950℃,40MPa,保温保压1h)制备的两种超高温陶瓷,ZrB_2+20%SiC+5%X和ZrB_2+20%SiC+15%Y(体积分数)的抗热震性能进行了实验和理论研究。首先,在对两类材料的基本热学和力学性能参数进行系统测定的基础上,对它们进行从200℃到1000℃的热震处理,热震介质(水)的温度分别从

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链霉菌是十分重要的一类放线菌,绝大多数的抗生素都由该类细菌产生。毛壳属真菌是一类重要的丝状真菌,从中也发现有很多结构新颖、活性独特的活性物质。因此本论文对两株链霉菌的活性成分及一株金毛壳菌的次生代谢产物进行了研究。 1.从吸水链霉菌(Streptomyces hygroscopicus 1.358)液态发酵产物(乙酸乙酯提取物)中分离得到3个化合物,通过波谱方法鉴定为RK955A (1)、Nigericin(2)、Elaiophylin(3)。以青霉素耐药-金黄色葡萄球菌作为指示菌的抗菌活性测定表明,三者均具有较强抗菌活性。 2.通过抗肿瘤体外活性筛选模型筛选得到得到一株链霉属土壤放线菌,从中分离得到六个化合物:苯乙酰胺(4)、苯丙酰胺(5)、肉桂酰胺(6)、3-(N-(甲酰胺基)乙酰基)吲哚(7)、鸟苷磷酸(8)、鸟苷(9)。 3.从金色毛壳菌(Chaetomium aureus)的固态培养物中分离得到13个化合物,利用波谱方法将其鉴定为:金毛壳菌素A(10)、金毛壳菌素B(11)、Eugenetin(12)、Eugenitol(13)、Chaetoquadrin A(14)、Chaetoquadrin B(15)、Chaetoquadrin G(16)、Chaetoquadrin H(17)、Chaetochromin A(18)、Sterigmatocystin(19)、O-methylsterigmatocystin(20)、3β-羟基-麦角甾-5,7,22-三烯(21)和过氧麦角甾醇(22)。 4.综述了聚醚类抗生素的结构、生物合成、生物活性及作用机理。 The genus Streptomyces (Actinomycetes) is an important group of microbe. Most antibiotics known nowdays are discovered from species of Streptomyces. The fungi of the genus Chaetomium have attracted much attention because various kinds of secondary metabolites with diverse bioactivities have been found from them. Thus, the bioactive compounds from two strains of Streptomyces and the secondary metabolites of Chaetomium aureus were investigated. 1. Three compounds were isolated from the ethyl acetate extract of the fermentation broth of Streptomyces hygroscopicus. They are identified to be elaiophylin (1), nigericin (2), and antibiotic RK955A (3) on the basis of their spectroscopic data. Compounds 1-3 possess antibacterial activities against Staphyloccocus aureus. 2. It was found that the extract of the fermented broth of a strain of Actinomycetes could inhibit some tumor cel lines. Separation of the bioactive fraction led to the isolation of six compounds. They were characterized to be phenylacetamide (4), phenylpropylamide (5), trans-cinnamamide (6), 3- (N- (formylmethyl) acetamide) indole (7), guanylicacid (8), and guanosine (9). 3. From the fermented broth of Chaetomium aureus, 13 compounds were isolated for the first time. They were determined to be chaetomiumycin A (10), chaetomiumycin B (11), eugenetin (12), eugenitol (13), chaetoquadrin A (14), chaetoquadrin B (15), chaetoquadrin G (16), chaetoquadrin H (17), chaetochromin A (18), sterigmatocystin (19), O-methylsterigmatocystin (20), 3β-hydroxyergosta-5, 7, 22-triene (21) and peroxy-ergosterol (22). Compounds 10 and 11 are new ones. 4. Structure, biosynthesis, biological activity, and mechanisms of polyether antibiotics were reviewed.

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本学位论文由两部分共3章组成。第一部分分别报道2种藏药唐古特瑞香和大果大戟化学成分的研究成果,从2种药用植物共分离鉴定了60个不同的化合物,其中12个为新结构,特别有意义的是发现了2个具有同一新骨架的二萜化合物。第二部分概述了大戟科植物多环二萜的研究进展。 第一部分包括第1和2章。在这2章中分别报道了唐古特瑞香(Daphne tangutica Maxim)和大果大戟(Euphorbia wallichii Hook. f. Fl)化学成分的分离纯化与结构鉴定。实验采用正、反相硅胶柱层析、薄层制备及HPLC等分离方法,从唐古特瑞香的根皮中共分离出32个化合物,通过红外、质谱及核磁共振等波谱方法鉴定了其中的31个,结构类型分别属于瑞香二萜类、木脂素类、香豆素类、苯丙素类及甾体类,其中有三个新的瑞香二萜型化合物,经波谱分析将它们的结构分别鉴定为1,2a-二氢-20-棕榈酰瑞香毒素、1,2a-二氢-5b-羟基-6a,7a-环氧-树脂大戟醇-14-苯甲酸酯及1,2b-二氢-5b-羟基-6a,7a-环氧-树脂大戟醇-14-苯甲酸酯,另外还有13个已知化合物为首次从该植物中分离得到。从大果大戟的根部共分离出33个化合物,鉴定了其中的30个,其主要成分为种类丰富的二萜,包括巨大戟烷型、续随子烷型、对映-阿替生烷型、对映-贝壳杉烷型、对映-松香烷型、ent-trachylobane型、对映-异海松烷型及一新骨架五环二萜ent-wallichane型,另外还有香豆素、甾体、三萜和一些简单的小分子化合物。其中新化合物有9个,经波谱分析将它们的结构分别鉴定为5-O-(2E,4E,6E)-癸三烯酰基-3,20-O-二乙酰基巨大戟醇、5-O-(2E,4Z)-癸二烯酰基-3-O-乙酰基-20-去氧巨大戟醇、3-O-(2E,4Z)-癸二烯酰基-5b,6b-氧-交京大戟醇、7-苯甲酰氧基-3,5,15-三乙酰基-续随子醇、ent-trachylobane-3-one-17-oic-acid、3α-羟基-对映-阿替斯-16-烯-14-酮、3α,6-二羟基-对映-异海松-7-烯-2,15-二酮、wallichanol A 和 wallichanol B,其中,wallichanol A 和 wallichanol B属于一新骨架类型的五环二萜。除此以外,另有13个已知化合物为首次从该植物中分离得到。 第2部分即第3章,首次概述了大戟属植物中多环二萜的化学和药理研究进展。 This dissertation is composed by two parts. The first part reports the phytochemical investigation of two Tibetan medicine plants, Daphne tangutica Maxim and Euphorbia wallichii Hook. f. Fl. Sixty different compounds including ten new compounds and two novel diterpenoids possessing a new carbon skeleton were isolated and identified. The second part is a review about the progress of studies on the polycyclic diterpeniods of the plant family of Euphorbia. The first part consists two chapters, which expatiate on the isolation and identification of chemical constituents from D. tangutica and E. wallichii. Thirty-one compounds were isolated from the root barks of D. tangutica by methods of column chromatography (silica gel, including reversed phase), preparative TLC and HPLC, and their structure were identified as nine daphnane diterpenes, six lignans, nine cumarin derivatives, five phenylpropanoid derivatives, a steroids and a benzoate on the basis of spectroscopic methods including IR, MS and NMR. Among them, three are new diterpenes with skeleton of daphnane and the structure were determined as 1,a-dihydro-20-palimoyl-daphnetoxin, 1,2a-dihydro-5b- hydroxy-6a,7a-epoxy-resiniferonol-14-benzoate and 1,2b-dihydro-5b-hydroxy- 6a,7a-epoxy-resiniferonol-14-benzoate. In addition, thirteen known ones were isolated from this plant for the first time. Isolation of the roots of E. wallichii yielded thirty compounds, twenty-four of them were elucidated as diterpenoids, which belong to different skeleton types of ingenol, lathyrane, ent-atisane, ent-kaurane, ent-abietane, ent-trachylobane, ent-isopimarane and a new pentacyclic skeleton ent-wallichane respectively. The remains including a cumarine, a triterpenoid, a steroid and three compounds with small molecule. Nine new compounds were characterized as 5-O-deca-2E,4E,6E- trienoyl-3,20-O-diacetylingenol, 5-O-deca-2E,4Z-dienoyl-3-O-acetyl-20- deoxyingenol, 3-O-deca-2E,4Z-dienoyl-jolkinol-5b,6b-oxide, 7-benzoyl-3,5,15- triacetyl-7-hydroxylathyrol, ent-trachylobane-3-one-17-oic-acid, 3α-hydroxy-ent- atis-16-en-14-one, 3α,6-dihydroxy-ent-isopimarane-7-en-2,15-dione, wallichanol A and wallichanol B, respectively, by means of comprehensive spectroscopic analysis. Among them, wallichanol A and wallichanol B were two notable novel pentacyclic diterpenoids processing a new rearranged carbon skeleton. And more, thirteen ones were firstly reported from this plant. The third chapter summarizes the research development on chemistry and pharmacology of polycyclic diterpenes from the plant family of Euphorbia for the first time.

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由于人类活动所引起的地球大气层中温室气体的富集已导致全球地表平均温度在20世纪升高了0.6 ℃,并预测在本世纪将上升1.4-5.8 ℃。气候变暖对陆地植物和生态系统影响深远,并已成为全球变化研究的重要议题。高海拔、高纬度地带的生态系统对气候变化最敏感。而在高原和高山极端环境影响下所形成的高寒草甸生态系统极其脆弱,对由于温室效应引起的全球气候变化极其敏感,对这些变化的响应更具有超前性。 本研究以川西北高寒草甸植物群落及几种主要物种为研究对象,采用国际山地综合研究中心(ITEX)普遍所采用的增温方法-----开顶式生长室(OTC)模拟气候变暖来研究增温对高寒草甸植物群落结构、物质分配及其主要物种生长和生理的影响,以探讨高寒草甸植物响应与适应气候变暖的生物学和生态学机制。主要研究结论如下: 1、OTC的增温效果 由于地温、地表温度和气温的平均值在OTC内分别高出对照样地0.28℃、0.46℃和1.4℃,这说明本研究所采用的开顶式生长室(OTC)起到了增温的作用;同时,由于温室内与温室外接受的降水量相同,温室内由于热量条件的改善,土壤蒸发和植被的蒸腾作用增强,直接导致了OTC内土壤表层相对湿度的减少。 2、群落结构对增温的响应 由于增温时间较短,增温内外样地的物种组成并未发生改变;但增温后一定程度上改变了植物群落的小气候环境,从而导致物种间的竞争关系被破坏,种间竞争关系的破坏引起群落优势种组成发生相应的改变,在对照样地,鹅绒委陵菜、甘青老鹳草、遏蓝菜和蚤缀是占绝对优势的物种,而在OTC内,小米草、尼泊尔酸模、垂穗披碱草、发草和羊茅的重要性显著增加。 禾草和杂草由于对增温的生物学特性及其资源利用响应的不同,加之增温造成土壤含水量下降等环境因子的改变。与对照样地相比较,OTC内禾草的盖度及生物量都显著增加,而杂草的盖度和生物量则显著下降。 3、植物生长期对增温的响应 OTC内立枯和调落物的生物量在生长季末(10月份)都要小于对照样地的立枯和调落物生物量,而OTC内的地上鲜体生物量在10月份却略高于对照样地。这说明OTC内植物的衰老或死亡得以延缓,而植物的生长期得以延长。 4、群落生物量及分配对增温的响应 OTC内的地上鲜体生物量(10月份除外)和地下0-30cm的根系生物量与对照样地相比较,都出现了不同程度的减少;土壤根系的分配格局也发生了明显的改变,其中,OTC内0-10cm土层的生物量分配比例增加,而20-30cm土层生物量分配比例的减少。 5、群落碳、氮对增温的响应 增温后,OTC内植物群落地上活体和地下活根的碳浓度不同程度的高于对照样地,植物群落的碳库在OTC内也略高于对照样地;而OTC内植物群落地上活体和地下活根的氮浓度不同程度的低于对照样地,其植物群落的氮库与对照样地相比也略有下降。 6、几种主要植物的生长及物质分配对增温的响应 垂穗披碱草在增温后株高、比叶面积和地上生物量均显著地增加;尼泊尔酸模在增温后比叶面积和单株平均生物量积累显著地增加,而各组分中,增温处理使叶的生物量显著增加,而根的生物量却显著下降;鹅绒委陵菜在增温后株高、比叶面积和单株平均生物量积累显著地减少,而各组分中,增温处理使叶和茎的生物量显著减少,根的生物量却显著地增加。 尼泊尔酸模的LMR、RMR、R/S、根部碳含量、碳和氮在叶片与根部的分配比例在增温后显著地增加,而SMR、根部氮含量、碳和氮在茎部的分配比例在增温后却显著地降低;鹅绒委陵菜的RMR、R/S、碳和氮在根部的分配比例在增温后显著地增加,而SMR、LMR、碳在叶片的分配比例在增温后却显著地降低 7、几种主要植物的光合生理过程对增温的响应 增温使垂穗披碱草和尼泊尔酸模叶片中的叶绿素a、叶绿素b、总叶绿素含量显著增加;而鹅绒委陵菜叶片的叶绿素a、叶绿素b、总叶绿素含量在增温后显著减少,类胡萝卜素含量在增温后却显著增加。 增温对3种植物的气体交换产生了显著影响。其中,垂穗披碱草和尼泊尔酸模叶片的光响应曲线在增温后明显高于对照处理,A、E、gs、Pmax、、Rday、AQY和LSP显著增加,而LCP则显著降低;鹅绒委陵菜的光响应曲线在增温后则明显的低于对照处理,A、E、gs、Pmax、、Rday、AQY和LSP显著减少,而LCP则显著增加。 增温后垂穗披碱草和尼泊尔酸模叶片的Fv/Fm、Yield和qP显著增加;而鹅绒委陵菜叶片的Fv/Fm、Yield和qP则显著减少,qN却显著地增加。 8、几种主要植物的抗氧化酶系统对增温的响应 增温使垂穗披碱草和尼泊尔酸模体内抗氧化酶活性和非酶促作用有所提高,植物膜脂过氧化作用降低;鹅绒委陵菜叶片中酶促反应和非酶促反应在增温后也显著提高,但可能由于增温后的土壤干旱超过了鹅绒委陵菜叶的抗氧化保护能力,抗氧化酶活性及非酶促反应(脯氨酸、类胡萝卜素)的提高不足以完全清除干旱诱导形成的过量活性氧,因此叶片的膜脂过氧化程度仍然显著提高。 Enrichment of atmospheric greenhouse gases resulted from human activities such as fossil fuel burning and deforestation has increased global mean temperature by 0.6 ℃ in the 20th century and is predicted to increase in this century by 1.4-5.8 ℃. The global warming will have profound, long-term impacts on terrestrial plants and ecosystems. The ecoologcial consequences arising from global warming have also become the very important issuses of global change research. The terrestrial habitats of high-elevation and high-latitude ecosystems are regarded as the most sensitive to changing climate. The alpine meadow ecosystme, which resulted from the composite effects of mountain extreme climatic factors in Tibetan Plateau, is thus thought to be especially vulnerable and sensitive to global warming. In this paper, the response of plant community and several main species in the alpine meadow of Northewst Sichuan to experimemtal warming was studied by using open-top chambers (OTC). The aim of the this study was to research the warming effects on plant community structure, substance allocation, growth and physiological processes of several mian species, and to explore the biological and ecological mechanism of how the alpine meadow plants acclimate and adapt to future global warming. The results were as follows: 1. Warming effects of OTC The mean soil temperature, soil surface temperature and air temperature in OTC manipulation increased by 0.28℃、0.46℃ and 1.4℃ compared to the control during the growing season. This suggested that the OTC used in our study had increased temperature there. Meanwhile, the OTC manipulation slightly altered thermal conditions, but the same amount of precipitation was supplied to both the OTC manipulation and the control, so higher soil evaporation and plant transpiration in OTC manipulation directly lead to the decrease of soil surface water content. 2. The reponse of community structure to experimental warming The species richness was not changed by the short-term effect of OTC manipulation. However, experimental warming changed the microenvironment of plant community, therefore competitive balances among species were shift, leading to changes in species dominance. In the present study, the dominant plant species in the control plots were some forbs including Potentilla anserine, Geranium pylzowianum, Thlaspi arvense and Arenaria serpyllifolia, however, the importance value of some gramineous grasses including Elymus nutans, Deschampsia caespitosa, Festuca ovina, and some forbs including Euphrasia tatarica and Rumex acetosa significantly increased in OTC. The different biology characteristics and resource utilizations between gramineous grasses and forbs, and enhanced temperature caused change in some environment factors such as soil water content. As a result, the coverage and biomass of gramineous grasses significantly increased in OTC compared to the control, however, the coverage and biomass of forbs singnifciantly decreased in OTC compared to the control. 3. The reponse of plant growing season to experimental warming Both the standing dead and fallen litter biomass in OTC were lower than those in the control in October, and the biomass of aboveground live-vegetation in OTC was higher than that of the control. The results indicated that the senescence of plants was postponed, and the growing season was prolonged in our research. 4. The reponse of community biomass accumulation and its allocation to experimental warming Experimental warming caused the decrease of aboveground live biomass and belowground root biomass except for the aboveground live biomass in October. Experimental warming also had pronounced effects on the pattern of root biomass allocation. In the present study, the root biomass in 0-10cm soil layer increased in OTC manipulation compared to the control, however, the root biomass in the 20-30cm soil layer decreased in OTC manipulation compared to the control. 5. The reponse of community C and N content to experimental warming The C concentration and stock in aboveground live and belowground root both increased in OTC manipulation compared to the control. However, the N concentration and stock in aboveground live and belowground root both decreased in OTC manipulation compared to the control. 6. The reponse of gowth and biomass, C and N alloction of several species to experimental warming Experimental warming significantly increased the height, SLA (specific leaf area) and aboveground biomass of Elymus nutans in OTC manipulation compared to the control. The SLA and total biomass of Rumex acetosa also significantly increased in OTC manipulation compared to control, among the different components of Rumex acetosa, leaf biomass significantly increased, but root biomass significantly decreased in OTC manipulation compared to the control. However, the height, SLA and total biomass of Potentilla anserina significantly decreased in OTC manipulation compared to the control, among the different component of Potentilla anserina, leaf and stem biomass significantly decreased, but root biomass significantly increased in OTC manipulation compared to the control. The LMR (leaf mass ratio), RMR (root mass ratio), R/S (shoot/root biomass ration) and root C concentration of Rumex acetosa significantly increased in OTC manipulation compared to outside control, also, Rumex acetosa allocated relatively more C and N content to leaf and root in response to experimental warming, however, the SMR (stem mass ration) and root N concentration of Rumex acetosa significantly decreased in OTC manipulation compared to outside control, also, Rumex acetosa allocated relatively less C and N content to stem in response to experimental warming. The RMR and R/S of Potentilla anserina significantly increased in OTC manipulation compared to outside control, also, Potentilla anserina allocated relatively more C and N content to root in response to experimental warming, however, the SMR and LMR of Potentilla anserina significantly decreased in OTC manipulation compared to outside control, also, Potentilla anserina allocated relatively less C and N content to leaf in response to experimental warming. 7. The reponse of physiological processes of several species to experimental warming Experimental warming significantly increased chlorophyll a, chlorophyll b and total chlorophyll of Elymus nutans and Rumex acetosa in OTC manipulation compared to outside control. However, chlorophyll a, chlorophyll b, total chlorophyll and carotenoid of Potentilla anserina in OTC manipulation significantly decreased compared to outside control. Experimental warming had pronounced effects on gas exchange of Elymus nutans, Rumex acetosa and Potentilla anserine. In the present study, warming markedly increased the light response curves of Elymus nutans and Rumex acetosa in OTC manipulation compared to outside control, and also singnificantly increased A (net photosynthesis rate), E (transpiration rate), gs (stomatal conductance), Pmax (maximum net photosynthetic rate), Rday (dark respiration rate), AQY (apparent quantum yield) and LSP (light saturation point), but LCP (photosynthetic light compensation) of Elymus nutans and Rumex acetosa in OTC manipulation singnificantly decreased compared to outside control. However, warming markedly decreased the light response curves of Potentilla anserina in OTC manipulation compared to outside control, and also singnificantly decreased A, E, gs, Pmax, Rday, AQY and LSP, but LCP of Potentilla anserina in OTC manipulation singnificantly increased compared to outside control. Experimental warming singnificantly increased the chlorophyll fluorescence kinetics parameters such as Fv/Fm, Yield and qP of Elymus nutans and Rumex acetosa and qN of Potentilla anserina in OTC manipulation, but Fv/Fm, Yield and qP of Potentilla anserina in OTC manipulation singnificantly decreased. 8. The reponse of antioxidative systems of several species to experimental warming Experimental warming tended to increase the activities of antioxidative enzymes and stimulate the role of non-enzymes of Elymus nutans and Rumex acetosa. As a result, MDA content of Elymus nutans and Rumex acetosa decreased. The activities of antioxidative enzymes and non-enzymes of Potentilla anserina also significantly increased in OTC manipulation, but more O2- was produced because of lower soil water content, and the O2- accumulation exceeded the defense ability of antioxidative systems and non-enzymes fuctions. As a result, MDA content of Potentilla anserine still increased in OTC manipulation compared to outside control.

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全球气候变化已经成为不争的事实,其中全球变暖是近年来国内外的研究热点之一。土壤碳库作为陆地生态系统最大的碳库,气温升高必然会导致一系列的土壤碳储量和碳通量的变化,这些微小的变化又可能导致大气CO2浓度的变化并强化这种变暖的趋势。目前,土壤碳循环对温度升高的响应仍然是陆地碳循环研究最缺乏的部分,对土壤有机碳动态变化的研究仍存在着很大的不确定性与争议。四川西部的亚高山人工针叶林是青藏高原东部高寒林区的重要组成部分,是研究全球变化对森林生态系统影响的关键地区和重要森林类型。本研究通过采用原位人工模拟增温装置(Open-top chambers,OTCs)对川西米亚罗60年人工云杉林土壤实施增温,研究高海拔地区森林,尤其是人工森林系统下的土壤有机碳 含量、土壤呼吸及土壤酶活性对温度升高的响应。结果表明: 1. 增温处理的660天(2005年11月至2007年9月)期间,增温条件下的平均气温和土壤平均温度分别比对照提高0.43 ℃和0.27 ℃;0~10 cm土壤含水量在增温的不同时期均有不同程度的降低。 2. 土壤蔗糖酶、蛋白酶和脲酶活性在温度升高的不同阶段均有不同程度的提高。在增温处理300天(2006.09)、540天(2007.05)、600天(2007.07)和660天(2007.05)后,0~10 cm层的蔗糖酶活性分别比对照提高了36.36%(P<0.05)、24.31%、14.54%(P<0.05)和7.22%,脲酶活性分别提高了12.90%、24.19%(P<0.01)、34.48%(P<0.05)和14.64%(P<0.05),蛋白酶活性分别提高了31.37%、1.99%、3.70%和17.80%。10~20 cm层的土壤酶活性也均有不同程度的提高,但均没有显著差异。蔗糖酶、脲酶和蛋白酶活性均呈现出随土层加深而减弱的趋势。 3. 土壤过氧化氢酶和多酚氧化酶活性在增温的第1年内均有不同程度的提高,但在增温的第2年内比对照有所降低。增温300天后(2006.09),过氧化氢酶和多酚氧化酶在0~10 cm层分别比对照增加3.76%和49.25%(P<0.05),10~20 cm层分别增加了5.54%和29.67%。在增温的第2年内,增温540天(2007.05)、600天(2007.07)和660天(2007.09)后,0~10 cm层的过氧化氢酶活性分别比对照降低了27.70%(P<0.05)、4.34%和1.47%,多酚氧化酶活性分别降低了5.86%、11.76%(P<0.05)和7.47%。增温的第2年内,10~20 cm层的过氧化氢酶和多酚氧化酶活性也均有不同程度的降低,但差异均未达到显著水平。不同土层之间相比较,过氧化氢酶活性随土层加深而降低,多酚氧化酶活性随土层加深而增加。 4. 土壤有机碳和有机质在增温的不同阶段,含量比对照均有所降低;且随增温时间的延长,降低的幅度下降。0~10 cm层的土壤有机碳和土壤有机质在增温300天(2006.09)、540天(2007.05)、600天(2007.07)和660天(2007.09)后分别降低了8.69%、4.35%、3.80%和2.44%,差异均未达到显著水平。土壤全氮含量在增温后与对照相比无明显的增加或者降低趋势。增温条件下的土壤C/N比与对照相比有所降低,但在增温各阶段的差异均不显著。10~20 cm层的有机碳、有机质和C/N比也有不同程度的降低趋势,但差异均不显著。不同土层之间相比,0~10 cm层的有机碳、有机质、全氮含量和C/N比均高于10~20 cm层,呈现出随土层加深而降低的趋势。 5. 土壤呼吸速率在增温第1年内,与对照相比明显提高,但在增温处理2年后,与对照相比无显著变化。增温300天(2006.09)和360天(2006.11)后分别提高了13.32%和21.17%,差异显著。增温处理540天(2007.05)到660天(2007.09)期间,与对照相比,不仅没有明显的提升,反而有些月份比对照有所降低,对温度升高的敏感性降低,呈现出对温度升高的适应性。土壤呼吸的日呼吸速率呈现单峰曲线形式,在14:00~20:00期间达到最大值,在4:00~10:00期间具有最低值。土壤呼吸的季节变化,呈现出与外界环境温度相一致的趋势,在7月份(夏季) 最高,11月份(冬季)最低。土壤呼吸与2 cm土壤温度、5 cm土壤温度和空气温度均呈极显著指数相关,与0~10 cm土壤含水量呈线性相关,相关性达到显著水平,但低于土壤呼吸与温度的相关性。 The past century has seen a marked increase in atmospheric carbon dioxide concentrations and a concomitant warming that has drawn scientific attention to the link between global carbon stocks and climate change. In particular, the decomposition and turnover of soil organic matter is recognised as an important determinant of carbon driven climate change. The slightly variation in soil organic carbon will result in the increase of atmospheric carbon dioxide concentrations and reinforce the tendency of warming. The experiment was conducted in Subalpine coniferous forest in western Sichuan province. Subalpine coniferous forest in western Sichuan was a important part of eastern Qinghai-Tibetan Plateau, which play a important role in reseaching the sensitivity of forest ecosystem to climate change. To investigate the effects of elevated temperature on soil organic carbon content, soil respiration rates, and soil enzyme activities in subalpine Picea asperata plantations, a esimulated warming measure was applied with Open-top chambers. The results were as followed: 1) During the period from Nov. 2005 to Sep. 2007, mean air temperature and soil temperature were respectively 0.43℃ and 0.27℃ the ambient higher. Soil water content decreased to different exent in different months in warmed plots than in unwarned plots at depth of 0-10 cm. 2) In general, elevated temperature enhanced the soil enzyme activities of invertase, protease, and urease. In the first year of warming—after 300 days’ treatment (in Sep,2006), the activities of invertase, protease, and urease increased by 36.36%, 12.90% and 31.37% respectively at the depths of 0-10 cm,among which the activity of invertase reached statistic significance. In the second year of warming, invertase activity increased by 24.31% after 540 days’ treament (in May, 2007), 14.54% after 600 days’ treament (in Jul, 2007) and 7.22% after 660 days’ treatment (in Sep, 2007) at the depths of 0-10 cm, and the differences in July and Septemmber were statistically significant. Elveated temperature also increased the activity of urease in the second year of warming and had significant effects in May and July. The activity of protease in warmed plots was also higher than in unwarmed plots at depths of 0-10 cm, but there was no significant difference. Elevated temperature had no significant effects on all soil enzyme acitivities at the depths of 10-20 cm in the first and sencond year. The values of above-mentioned soil enzyme all decreased with soil layers. 3) Eleavted temperature enhanced the activities of catalase and polyphenol oxidase in the first year of warming while they turned out downtrend in the second year. The activity of catalase increased by 3.76% and 5.54% at depths of 0-10 cm and 10-20 cm respectively in the first year—after 300 days’ warming (in Sep, 2006), the differences of which had no statistical significance. The activity of polyphenol oxidase was significantly increased by 49.25% at depths of 0-10 cm and not significantly increased by 29.67% at depths of 10-20 cm after 300 days’ warming. In the second year of warming, the catalase activity was significantly decreased by 27.70% after 540 days’ treament (in May, 2007) and not significantly decreased by 4.34% and 1.47% after 600 days’ (in Jul, 2007) and 660 days’ treament (in Sep, 2007) respectively. The activities of catalase and polyphenol oxidase at depths of 10-20 cm were decreased to different extent, but there was no significant difference. Catalase activity stepped down with soil layers while polyphenol oxidase activity stepped up. 4) Increased temperature in both the first year and the second year resulted tendency of decrease in the contents of soil organic carbon and soil organic matter, and C/N ratios at soil depths of 0-10 cm and 10-20 cm. However, with the prolonged warming, the tendency of decrease gradually tapered off and the extent of decrease in the second year of experiment were lower than that in the first year. The contents of soil organic carbon and soil organic matter were all decreased 8.69% by warming in the first year and dcreased 4.35%, 3.80% and 2.44% in May, July and September of the second year, but no significant difference were found. The C/N ratios increased 8.52% in the first year of warming and had less increment in the second year, all of which were not statistical significant. Eleveated temperature had no obvious effect on the content of tatol N in two year consecutive warming experiment. The contents of soil organic carbon and soil organic matter, total N and C/N ratios all had the tendency of dcreasing with soil layers. 5) Soil respiration rates were significantly enhanced by 13.32% and 21.17% after 300 days’ (in Sep, 2006) and 360 days’ (in Nov, 2006) treament in the first year of warming, but the same showed no obvious difference in the second year of treatment, which was assumed the adaptability of soil respiration with a certain heightened temperature. Diurnal soil resspiration showed a daily variation with a minimum value between 4:00 and 10:00 h and a maximum value between 14:00 and 20:00 h, coinciding with the minimum and maximum values of soil temperature at 2 cm. Soil respiration rates exhibited a pronounced seasonal variation with minimum values in Novmber and a maximum value in July, approximately coinciding with the seasonal variation of air and soil temperature. An exponential function provided the best fit for soil respiration with temperature while a quadric equation was used to estimate the effect of soil moisture on soil respiration, which were all significantly correlated. Soil respiraion rate was more highly correlated with the soil temperature than soil moisture.

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小麦条锈病(Puccinia striiformis f. sp. tritici)是世界性小麦病害,可导致受害小麦减产30%以上,甚至绝收。小麦条锈病在我国西南、华北麦区危害严重,四川麦区是小麦条锈病发病最重的地区之一,每年因条锈病流行造成小麦产量损失巨大。利用抗条锈病品种是控制该病害最安全、经济的有效途径,因此挖掘利用抗病新基因,开展抗病遗传基础研究是当前育种工作中面临的重要任务。 偏凸山羊草(Aegilops ventricosa,DDMvMv,2n=28)是一年生草本植物,起源于地中海西部沿岸地区,具有对小麦白粉病、锈病等高抗或免疫、耐盐、抗寒、蛋白质含量高等优良性状,是小麦遗传育种很好的种质资源。本研究以高抗条锈病的小麦—偏凸山羊草6Mv/6B代换系(Moisson 6Mv/6B)为材料,对其含有的带条锈病抗性基因的偏凸山羊草6Mv染色体在四川小麦背景中的传递情况、与小麦—簇毛麦双端体附加系所具有的白粉病抗性的聚合以及对Moisson 6Mv/6B进行电离辐射诱变筛选抗条锈病的小麦—偏凸山羊草易位系三个方面进行了研究。取得的主要研究结果如下: 1. Moisson 6Mv/6B与高感条锈病的四川地区普通小麦品种绵阳26、绵阳93-124和SW3243的杂种F1与其普通小麦亲本分别作为父、母本回交,通过对其BC1和F2的结实率、根尖细胞有丝分裂中期染色体的观察以及对条锈病抗性的鉴定,发现含6Mv染色体的F1植株作母本时的回交结实率(83.10%)普遍高于含6Mv染色体的F1植株作父本(48.61%),结实率与普通小麦基因型密切相关(χ2=34.15>>χ20.05=5.99(df=2));6Mv染色体在三种四川小麦中通过雌、雄配子传递的传递方式与其传递率间没有显著相关性,其传递率与普通小麦基因型呈显著相关性(χ2=6.42>χ20.05=5.99(df=2))。 2. Moisson 6Mv/6B与高抗白粉病的小麦—簇毛麦双端体附加系Pana(2n=42+2t)正反杂交,希望在聚合两者抗性的同时观察不同受体背景下的抗性反应。对Moisson 6Mv/6B和Pana正反杂交的结实率、杂交后代的农艺性状进行观察,并对杂交后代进行基因组荧光原位杂交(GISH)分析及条锈病和白粉病的抗性鉴定。结果表明Moisson 6Mv/6B作母本时杂交结实率(80.56%)高于Pana作母本时(58.33%),结实率与杂交方式间紧密相关(χ2=4.96>χ20.05=3.84(df=1));Moisson 6Mv/6B和Pana杂交后代株高比最高亲本高约10cm,成熟期也较两亲本提前两个星期左右;正反杂交后代中具有偏凸山羊草6Mv染色体的植株具有条锈病抗性,具有簇毛麦端体的植株具有白粉病抗性,同时筛选到4株含有偏凸山羊草和簇毛麦遗传物质并对条锈病和白粉病兼抗的材料,证明来自偏凸山羊草6Mv染色体的条锈病抗性与来自簇毛麦端体的白粉病抗性已经聚合在一起,且没有产生相互抑制的作用,暗示通过这两个抗性基因的聚合是完全能获得兼抗条锈病和白粉病的小麦新种质。 3. 对Moisson 6Mv/6B在减数分裂时期的成株进行总剂量为6Gy、辐射频率为120rad/min的60Co-γ射线辐射,对辐射植株自交后代进行农艺性状及根尖细胞有丝分裂中期染色体形态观察和条锈病抗性鉴定。结果为辐射植株自交结实率为2.22%,根尖细胞有丝分裂中期的染色体存在明显碎片,辐射自交后代植株对条锈病具有成株期抗性。 小麦—偏凸山羊草6Mv/6B代换系对条锈病抗性稳定,是培育条锈病抗性品种的良好供体。本研究证明在四川小麦背景中要利用该品种抗性,在结实数满足需要时,可将其作父本,亦可作母本,但关键是要选择好一个优良的受体基因型;同时其条锈病抗性与来自簇毛麦的白粉病抗性没有相互抑制作用,可将两者抗性有效聚合用于小麦育种中。 Wheat stripe rust (Puccinia striiformis f. sp. Tritici) is a worldwide disease of wheat, and could lead to victims of 30 percent or even total destruction of wheat production. Wheat stripe rust harms badly in China's southwest and North China. Sichuan province is one of the regions damaged by wheat stripe rust heavily. The use of resistant varieties is the most secure and economical way to control the wheat stripe rust. Therefore, it is essential to identify new disease-resistant genes and genetically research of disease resistance. Aegilops ventricosa (DDMvMv, 2n = 28) is an annual herbaceous plant, originating in the coastal areas of the western Mediterranean, with good characters such as resistance of wheat powdery, rust, salt, cold and high protein content. It is a good germplasm resource. In this study, the wheat- Aegilops ventricosa 6Mv/6B substitution line Moisson 6Mv/6B (highly resistant to the wheat stripe rust) was used to study on the transmission of chromosome 6Mv of Aegilops ventricosa in different genetic background of Sichuan wheat varieties, hybridization with wheat- Haynaldia villosa ditelosomic addition line Pana (highly resistant to the powdery mildew) and screening of wheat- Aegilops ventricosa translocation line by exposuring Moisson 6Mv/6B under ionizing radiation. The main results are as following: 1. Moisson 6Mv/6B was crossed with Sichuan wheat varieties mianyang26, mianyang93-124 and SW3243 (highly susceptible to stripe rust), respectively. Their F1 hybrids were further backcrossed as male and female to corresponding wheat varieties. The seed-setting rate, chromosomes confirmation in the mitotic metaphase of root tip cells, and resistance to stripe rust of the subsequent BC1 and F2 plants were investigated. The average seed-setting rate of backcross via 6Mv as female donor (83.10%) was higher than that of backcross via 6Mv as male donor (48.61%), suggesting that the seed-setting rate was associated with the wheat genotypes(χ2=34.15>>χ20.05=5.99(df=2)). In all analyzed populations, transmission frequencies of chromosome 6Mv were not correlated with the ways of 6Mv through male or through female. However, transmission frequencies of chromosome 6Mv were significantly correlated with Sichuan wheat genotypes(χ2=6.42>χ20.05=5.99(df=2)). 2. To aggregating the resistances to stripe rust and powdery mildew, as well as research on the resistance reactions in different genetic background, Moisson 6Mv/6B was reciprocally hybrided with the wheat- Haynaldia villosa ditelosomic addition line Pana (highly resistant to the powdery mildew). The seed-setting rate, agronomic characters, genomic in situ hybridization (GISH) of hybrid progenies,and resistances to stripe rust and powdery mildew were investigated. The results showed that the seed-setting rate of hybridization via Moisson 6Mv/6B as female donor (80.56%) was significant higher than that via Pana as female donor (58.33%). The seed-setting rate was associated with the hybrid methods (χ2 = 4.96> χ20.05 = 3.84 (df = 1)). The plant height of hybrid progenies was about 10 cm higher than Pana, the parent with maximum height. And the maturity of hybrid progenies was about two weeks earlier than that of the parents. In the hybrid progenies, the plants with the 6Mv chromosome have the resistance to stripe rust and the plants with the telosome from Haynaldia villosa have the resistance to powdery mildew. It was found that four plants with both the 6Mv chromosome and the telosome from Haynaldia villosa were resistant to stripe rust and powdery mildew. It indicated that the resistance to stripe rust and powdery mildew aggregated, and no mutual inhibition was found. It implied that the aggregation of the two resistance genes was able to provide the new wheat germplasm with the resistances to stripe rust and powdery mildew. 3. Moisson 6Mv/6B was irradiated with 60Co-γ rays of 6Gy (120rad/min) during meiosis. The agronomic characters and chromosomes confirmation in the mitotic metaphase of root tip cells,as well as resistance to stripe rust were investigated. The seed-setting rate of irradiated plants was only 2.22%. The chromosomes in mitotic metaphase had clear fragments. The resistance to stripe rust of progeny of irradiated plants was the adult-plant resistance. The wheat- Aegilops ventricosa 6Mv/6B substitution line is a good stripe rust resistance donor for its stabile resistance. Our study demonstrated that the key for use the resistance is to choose a good receptor. There is no difference between Moisson 6Mv/6B be the female and be the male if the seed number meets the requirement. At the same time, the stripe rust resistance of Moisson 6Mv/6B did not have the mutual inhibition with the powdery mildew resistance from Haynaldia villosa. It is able to aggregate the two resistances for wheat breeding.

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通过单因子和多因子摇瓶正交试验,确定了米曲霉液态发酵产氨基酰化酶的最佳发酵条件。优化发酵培养基组成(ρ/g L-1): 葡萄糖40,蔗糖10,可溶性淀粉20,蛋白胨2.5,马铃薯液1 000mL, pH自然。培养基装量50mL/250mL三角瓶,接种量4%。培养温度30℃,转速100 rmin-1,发酵时间42h。每50mL培养物的总酶活由优化前的2627U提高到7338U,是优化前的2.79倍。 研究了米曲霉氨基酰化酶的部分酶学性质,该酶催化反应的最适pH为7.0,最适温度为40℃,低浓度的Co2+(5×10-4mol/L)对酶活激活作用显著,催化反应过程中,底物浓度大于0.2 mol/L时,存在高浓度底物抑制酶活力现象。 初步探索了包埋法固定化米曲霉氨基酰化酶的载体,在实验的五种载体中,以海藻酸钠为载体包埋固定化米曲霉氨基酰化酶酶活保留率高,且操作简单,成本低廉。对包埋法固定化米曲霉氨基酰化酶酶学性质进行了研究,较游离米曲霉氨基酰化酶,最适温度未发生改变,最适pH向碱性范围偏移至8.0,对酸碱和热的稳定性增强,最适底物浓度增大到0.4 mol/L。 根据氨基酰化酶能立体专一水解L-氨基酰化物的特点,利用米曲霉氨基酰化酶对消旋苯丙氨酸进行了拆分。在米曲霉氨基酰化酶选择性的作用于底物N-乙酰-L-苯丙氨酸,得到L-苯丙氨酸后,通过732阳离子树脂和结晶法分别将L-苯丙氨酸和N-乙酰-D-苯丙氨酸分离,N-乙酰-D-苯丙氨酸通过酸水解脱去乙酰基得到D-苯丙氨酸,拆分得到光学纯度为98%的L-苯丙氨酸(收率84.8%)和光学纯度为92.3%的D-苯丙氨酸(收率89.5%)。 separate factors tests and orthogonal experiments,the optimum fermentation conditions of aminoacylase –producing Aspergillus oryzae were determined, as follows(ρ/g L-1),glucose 40,sucrose 10,soluble starch 20,peptone 2.5,potato juice 1000ml, inoculation volume 4%and fermentation temperature 30℃,rotation speed 100rmin-1.The highest total enzyme activity ,7338μ,was obtained after fermentation for 42 h, increased by 279% compared with the original value of 2627μbefore optimization. We dicussed partial characteristics of aminoacylase. The optimal pH and temperature of aminoacylase were 7.0 and 40℃ respectively. Low- concentration Co2+ (5×10-4mol/L)activated the aminoacylase remarkably while high-concentration substrate lowered the aminoacylase . Five vectors has been used for immobolizing the enzyme and calcium alginate showed to be the best one for it had the slightest influence on the enzyme activity, easy to operate ,and low in price, comparing with other fours. The enzymatic charateristic study showed that its optimum temperature didn’t change, but the optimum pH and substrat concentration were higher after immobilization. The stability of immobolized enzyme to acid, alkaline and heat rised as well. The aminoacylse from Aspergillus oryzae was used to resolute racemic phenylalanine to obtain D-phenylalanine. After catalyzing process, we took two methods to separate D-phenylalanine .In end,L-phenylalanine was obtained with 98% optical purity in 84.8% yield, D-phenylalanine was obtained with 92.3% optical purity in 89.5% yield.

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论述了一种小型化的成形放大(主放)与峰保持电路,主放成形时间常数分为0.5、1、2、3μs等4挡,放大倍数分×10、×100两挡,峰保持时间约6μs。电路主要采用通用集成电路构成,具有价格低、性能好和体积小的特点。

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利用 HIRFL (兰州重离子研究装置 )产生的 5 5 Me V/ u的4 0 Ar17+ 离子束 ,用由 Cs I(Tl) +快塑料闪烁探测器组成的 Phoswich探测器 ,以 1.5 mm有机玻璃为等效生物组织材料 ,探索了研究等效生物组织中核碎片测量的方法。对实验中可能出现的问题及解决方法进行了探讨。结果表明探测器对 Z可分辨到 16。元素分辨率为 Z/ ΔZ约为 4 0。

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藉助氦喷嘴带传输系统 ,采用“p γ”符合的鉴别原理 ,成功地合成与鉴别了5 8Ni(36 Ar,2p3n)反应产生的核素89Ru ,并研究了它的 β缓发质子衰变性质 .实验给出89Ru的衰变半衰期为 (1 .2± 0 .2 )s,测定了它的β缓发质子能谱 ,提取出了89Ru经缓发质子衰变布居到子核88Mo的 2 + 和 4+ 态的相对终态分支比 (1 0 0∶6 ) .通过与统计模型计算结果进行对比 ,初步指定了89Ru基态的自旋 宇称 (5 / 2 + 或 7/ 2 ±)和质量过剩 (- 5 9.5MeV) .