272 resultados para ICP


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有机化合物的选择氧化反应,特别是烃类的选择氧化,在石油化工中占有极其重要的地位。由于目标产物通常具有较高的活泼性,所以很难在高转化率条件下获得高选择性的氧化产物。因此对于催化研究者来说,如何控制深度氧化,提高目的产物的选择性始终是选择氧化,特别是烃类选择氧化研究中最具挑战性的技术难题。磷酸盐具有高度热稳定性,制备条件简单方便,原料价格低廉,而且其催化活性位区域易于与大分子反应等优点。其中磷酸钒、磷酸铁及其它过渡金属磷酸盐既具有氧化一还原性又有良好的表面酸性,在烃类等选择氧化反应中已表现出良好的催化性能,因而,研究磷酸钒、磷酸铁等磷酸盐催化剂在选择氧化中的催化作用具有重要的学术意义和应用前景。本论文主要在几个方面的工作研究了磷酸盐催化剂在气相选择氧化中的催化作用。探讨了过渡金属对层状磷酸钒的修饰,并以它们为催化剂前驱体,以甲苯气相选择氧化为探针反应,研究了过渡金属修饰对磷酸钒催化性能的影响。利用简单的方法直接合成了一个新的乙酞丙酮铜插层的层状磷酸钒,并用XRD、FTIR、ICP-MS、TGA和HRTEM对其进行了表征,确定合成的化合物分子式为:[Cu(acac)」0.5?VOH0.5PO4?0.5H2O。利用十二烷基胺通过简单直接的方法合成了中孔层状磷酸钒,并用XRD、FTIR?ICP一MS和TGA对其进行了表征,确定所合成的化合物主体磷酸钒为VOHPO4,十二烷基胺在VOHPo4的结构中通过与主体HPo4中的一H形成RNH3+和与VoHPO4层内的V=O形成氢键(V=O…H2NR)构成双层排列结构。利用烷基胺形成中孔层状结构的方法引入过渡金属钻和镍进入磷酸钒。以合成铜、钻和镍修饰的磷酸钒为前驱体,经焙烧后得到催化剂,甲苯气相选择氧化反应的结果表明,铜、钻和镍的修饰促进了磷酸钒的催化性能,提高了苯甲醛的选择性。发现了控制气相选择氧化产物选择性的新途径。以磷酸钒为催化剂,在环己烷、环己烯气相氧化反应中,通过在原料中加入醋酸改变了反应产物的分布,抑制了中间产物的深度氧化,可获得高选择性的目标产物。在反应温度450℃,当醋酸与环己烷、环己烯摩尔比为12.9:1和12.1:1时,分别获得了100%选择性的不稳定中间产物环己烯和1,3-环己二烯。研究了不同磷酸钒相对环己烷氧化脱氢反应的催化性能,表明在醋酸体存在条件下,催化性能顺序为:QI一OPO4>aII-VOPO4>pVOPO4>(VO)2P2O7。发现催化剂表面酸性强度不同和醋酸之间的相互作用力也不同,表面酸性越强;抗醋酸能力越强,活性中心与醋酸作用越弱,未与醋酸相互作用的活性中心数目越多,因此催化活性相对越高。同时,研究了不同载体对环己烯氧化脱氢的影响,比表面积越大,有利于提高催化剂的活性,但不利于获得高选择性的1,3-环己二烯;碱性载体有利于1,3-环己二烯的生成,但易于与醋酸反应而使催化剂失活。提出了醋酸在环己烷和环己烯氧化脱氢中作用机制:醋酸优于环己烷(烯)吸附在VPO催化剂表面活性位,这将导致在反应物吸附活性位周围几乎没有相邻的活性中心。即加入醋酸使催化剂表面形成了孤立的活性位,有利于中间物种不被继续氧化。利用上面的方法,以磷酸铁和磷酸钒为催化剂,实现了对甲酚气相选择氧化,获得100%选择性的对轻基苯甲醇、对经基苯甲醛和/或对轻基苯甲酸的混合物。与磷酸钒相比较,磷酸铁催化剂更温和,得到主要产物为对轻基苯甲醇和对经基苯甲醛;而磷酸钒催化剂更易产生深度氧化的产物对经基苯甲酸。这主要是由于他们表面酸性和氧化一还原性能的不同引起的。以磷酸铁、磷酸铜和磷酸秘为催化剂,探索了苯甲醇的气相选择氧化。研究了不同Fe(II)/Fe(III)比磷酸铁的催化活性。对于磷酸铁、磷酸铜和磷酸秘催化剂,最佳苯甲醛收率分别是在反应温度320℃、275℃和325℃,苯甲醛选择性分别为92.3%、97.1%、92.6%,相应苯甲醇的转化率为96.5%、60.9%和98.6%。

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本文使用一套以32MHz自激振荡高频发生器为电源的电感耦合等离子体光源与1米光栅摄谱仪联用,用三重石英炬管、玻璃同心雾化器及双层雾室研究了浓度为0~90%的乙醇溶液对某些元素的原子线及离子线强度的影响,并探讨了产生影响的原因。我们观察到:1.随着乙醇浓度的增大,所有“硬线”(离子张及高电离电位元素的原子线)的强度都有所提高,而对“软线”(中等以下电离电位的元素的原子线),其强度先是下降然后再提高。2.在固定的观察高度上,用一套钒线组,以斜率法测得的激发温度先是随乙醇浓度增大而上升,然后下降。3.乙醇浓度对喷雾器的提取率和有效提取率均有影响,后者随乙醇浓度的增加而增大。我们认为,乙醇浓度对谱线强度的影响主要是由于对激发温度和有效提取率的影响所引起的。在实验中还发现当将不同浓度的乙醇溶液喷入等离子体中时,高频发生器的阳流、栅流和频率等参数都发生有规律的变化;阳流、栅流都随乙醇浓度的增加而增大;振荡频率则相反。估计这是由于等离子体的阻抗发生变化所引起的。当将不同链长的醇类以及其它有机溶剂喷入等离子体时,上述三参数也发生有规律的变化。实验表明,在一定浓度范围内,乙醇溶液可以改善某些元素的检出限。在以上研究的基础上,提出根据将各种酒(啤酒、葡萄酒和烧酒)喷入等离子体中时,相应的阳流、栅流、振荡频率以及粘度值,来大致估计酒中的乙醇含量,并在标准溶液中加入相同量的乙醇来补偿乙醇对ICP感应耦合等离子体发射光谱的影响,研究了酒中主要基体元素对待测元素的影响,进行了最佳工作参数的选择。提出不用预处理,直接将酒试样喷入等离子体中进行多元素的同时测定。对某些元素的测定结果与原子吸收的测定结果作了对比,两者有较好的一致性。

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、I钠原子激光增强电离光谱(LEIS)方法的研究-以石墨杯为原子化器在LEIS方法中,最常见的原子化器是火焰。但由于火焰背景噪声严重且难以克服,在火焰原子化过程中,雾化和热离解不充分,仅有10~(-2)%的分析溶液参与吸收以及火焰气体使测定元素受到高度稀释等不利因素的影响,火焰原子化限制了LEIS方法灵敏度的进一步提高。考虑到石墨炉原子化器较火焰具有取样量少,绝对灵敏度高;样品(包括固态、液态)可直接引入石墨炉内;不会发生如同火焰中所存在的干扰效应;蒸发效率和原子化效率较高,几乎全部样品都能参与吸收等优点,本工作在已建立火焰LEIS方法的实验基础上,将原子化器改换为石墨杯进行了钠原子LEIS方法的研究。到目前为止,国内外仅有的几篇有关石黑炉LEIS的研究报告中,都报导了该方法对钠原子的检出限估计可达到10~(-14)-10~(-15)克,由于此项研究尚处于探索性研究阶段,故有关方法性的系统研究几乎还未见报导。本工作在未使用任何放大器的情况下(实验条件限制)对影响钠原子LEIS信号强度的诸因互进行了实验观察。主要包括:钠原子化条件;激光束位置、阳极电压、激光输出能量、电极位置以及激光脉冲重复率对LEIS信号强度的影响等。并绘制了校准曲线,统计方法的相对标准偏差分别为11%(高浓度)18.2%(低浓度),在现有仪器条件下,还不能测出检出限,测定下限为3*10~(-9)克。对固体粉末直接进行了尝试,检测下限为5*10~(-8)克,进样是为5毫克。在进一步的研究工作中,如有条件使用低噪声的放大器及Bxear积分器,选择门检时间窗,或采用分步激发等手段,估计本方法定会达到预想的高灵敏度,检敏度至少提高了个数量级。对石墨炉原子化LEIS法来说,似比较详细的研究报告,截至实验停止时还未见报导。II原子吸收光谱法对发样中Zn、Cu、Mn、Al的测定发中微量元素ZN、Cu、Mn均属人体必需元素,与人体的生长发育和多种生理功能,临床医学等方面有着极为密切的关系,而Al则被认为是异致某种疾病的元素之一。本工作报告了用火焰法测定Zn、Cu;石墨炉法测定Al、Mn的结果,其中,对Al的测定,为摆脱基体干扰,加入改进剂Mg(NO_3)_2,并采用平台石墨炉进行试验,得到了线性较好的工作曲线,但在实际测定时,由于实验条件的限制,只能采用一般石墨管加基体改进剂对少娄样品中Al含量进行测定。Zn、Cu、Al三种元素由标准曲线法测定;而Mn由于Fe的干扰无法消除而采用标准加入法测定,并因此限制了测定样品数。Cu、ZN、Mn三种元素的回收率分别为102.8%, 99.7%, 102.5%,变异系数为9.6%, 11.3%, 9.7%,对本地居民发中(30个发样)Zn、Cu含量进行测定,Zn、Cu的含量范围为148-318ppm,7.2-15ppm,并计算了Zn/Cu比。本方法对发样中四种元素的测定结果与ICP法进行对照。两种方法测定结果吻合得较好。

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本论文由三部分组成。第一部分是文献综述。首先从检出限、基体效应、光谱干扰及其校正、实际应用四个方面介绍了ICP-AES用于稀土元素分析的研究概况。然后,较全面深入地评述了有机试液的ICP-AES光谱分析技术的研究进展,讨论了有机溶剂对ICP放电稳定性的影响及提高稳定性的途径,有机试剂对背影和分析元素谱线强度的影响及其原因,比较了“有机ICP”和“水溶液ICP”的分析化学特性,详细地介绍了ICP-AES在各种有机试液直接分析中的应用。第二部分是稀土元素的ICP-AES分析的研究。首先测定了十五种稀土元素192条灵敏线的ICP-AES摄谱法的检出限和工作曲线线性范围。然后重点进行了乙醇溶剂的预去溶研究,即把预去溶进样的特点和乙醇的较高挥发性结合起来借以提高玻璃同心雾化器的进样效率,合稀土元素谱线速度显著增大,检出限改善5-12倍;同时研究了进样效率提高的机理以及去溶装置的去溶效率,发现残余乙醇进入ICP对谱线强度有抑制作用。详细地研究了由于乙醇导入ICP而产生的CN带对稀土元素灵敏线的干扰及CN带强率与ICP工作条件的关系,指出适当增加炸管的外管长度可以十分有效地抑制CN带。最后以纯Y_2O_3的ICP-AES分析为例,研究了基体对分析元素谱线强度的影响及基体效应的产生机理,提出用外加内标法代替通常的基体匹配法来克服基体效应,分析方法用于纯Y_2O_3中十四个稀土杂质的测定,获得较为满意的结果。第三部分是乙醇导入时ICP激发特性的研究,主要包括以下内容。(1)观察了乙醇对谱线强度的影响及这些影响与元素电离电位和谱线激发电位的关系,发现随乙醇浓度增大,经溶液进炬速率校正以后的“硬线”强度单调减小,而“软线”强度则出现极小值,以此结果为基础确定了某些未分类稀土元素光谱线的电离态并估测了它们的激发电位。(2)详细地研究了乙醇对ICP激发温度、气体温度、电子数密度以及易电离元素基体效应的影响,讨论了乙醇导入时分析元素在ICP中的电离过程的变化及“有机ICP”的热平衡特性。(3)研究了乙醇对ICP能量输适的影响,发现随乙醇浓度增大,等离子体电流减小,导致等离子体短体积增大(即“有机ICP”的扩张效应),可能使分析物在等离子体中的往向扩散得到增强。最后列出了305篇参考文献。全文共有图66个、表33个。

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感应耦合等离子体(ICP)刻蚀在AlGaN基紫外探测器台面制作中起着重要作用,初步研究了Cl2/Ar/BCl3ICP刻蚀对A1GaN材料的损伤。运用X射线光电子能谱(XPS)对ICP刻蚀前后的n型Al0.45Ga0.55N表面进行了分析,并对刻蚀后AlGaN材料在N2气中快速热退火进行了研究。结果表明,在N2气中550℃退火3min对材料的电学性能有明显的改善作用。

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通过单掩模紫外(UV)光刻、感应耦合等离子体(ICP)刻蚀及KOH:H_2O化学腐蚀,在硅片上制作5×5元面阵硅折射微光学结构.通过电化学方法将制成的硅精细图形结构转换成镍版,进而通过压制法将精细的镍版图形进一步转印到有机玻璃材料上,从而制成面阵光学波前出射结构.光刻版由结构尺寸在微米量级的大量微孔组成,其特征尺度和排布方式由算法生成.微形貌测试显示了制作的折射微光学波前出射结构具有预期的表面形貌特征.通过常规光学测试,比较和分析了出射复杂波前的情况.

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计算了GaN二维光子晶体的能带结构,并利用常规工艺在国内首次制备出了GaN基二维平板结构的光子晶体蓝光LED。经过器件测试表明,与没有制作光子晶体的器件相比,光子晶体使器件的有效出光效率达到了原来的1.5倍以上。另外,还对感应耦合等离子体刻蚀(ICP)的制备光子晶体LED的刻蚀工艺进行了分析。

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为实现基于InP/hGaAsP材料的二维光子晶体结构低损伤、高各向异性的干法刻蚀,研究了对InP材料基于C1_2,BCl_3气体的感应耦合等离子体刻蚀.从等离子体轰击使衬底升温的角度分析了刻蚀机理,发现离子轰击加热引起的侧蚀与物理溅射在侧壁再沉积之间处于平衡时可以得到高各向异性刻蚀,平衡点将随ICP功率增高而向偏压减小方向移动。从而在近203V偏压下得到陡直的侧壁.在优化气体组分后,成功实现了光于晶体结构高各向异性的低偏压刻蚀.

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为了从中枢神经系统记录电信号,半导体加工技术已经被用于微电极探针的制造.介绍了一种硅基探针的设计和制造工艺流程.我们已经制造出15 μm厚,3 mn长,100μm宽的记录用探针,每根探针含有7个记录点,间隔120 μm.在制造过程中使用微机械系统(MEMS)工艺中常用的硅表面微加工工艺:等离子增强化学气相淀积(PECVD),感应耦合等离子刻蚀(ICP)以及硅的各向异性刻蚀等.测试结果给出了探针的强度和阻抗特性.

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采用ICP刻蚀的方法,在SOI材料上制作出了中心波长为1.5509μm、信道间隔为200GHz的5×5阵列波导光栅(AWG).测试中心波长与设计值相差0.28nm,测试波长间隔与设计值相差在0.02nm之内,相邻信道串扰接近10dB,信道插入损耗均匀性为0.7dB,测试结果表明该器件能够初步达到分波功能.

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Equilateral triangle semiconductor microcavities with tensile-strained InGaAsP multi-quantum-well asthe active region are fabricated by the inductively coupled plasma (ICP) etching technique. The modecharacteristics of the fabricated microcavities are investigated by photoluminescence, and enhanced peaksof the photoluminescence spectra corresponding to the fundamental transverse modes are observed formicrocavities with side lengths of 5 and 10 μm. The mode wavelength spacings measured experimentallycoincide very well with those obtained by the theoretical formulae.

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揭示苔藓植株元素含量及其时空差异性是深入开展利用苔藓植物指示环境和筛选理想监测藓种的科学基础。采用微波消解(ICP-AES)方法对九寨沟自然遗产地原始林景点停车场周围三个采样带:I为停车场植被小岛(PS),向外约120 m半径为II带(D120),再向外距离约1,000 m为III带(D1000)和3个方向上的大羽藓和毛尖青藓2种苔藓中13种元素(A1, S, Ca, P, Cu, Fe, K, Mg, Mn, Pb, Ni,Zn和Cd)含量进行了测定和比较,并对采自边坡方向(PS-3)上2005和2007年的4种苔藓植物(南木藓、大羽藓、平藓和厚角絹藓)也进行了13种元素含量的测定和比较。同时对九寨沟自然遗产地、黄龙自然遗产地、夹金山和梦笔山的冷杉原始林4个地区的3种苔藓中(大羽藓、锦丝藓和塔藓)的A1、Ca、Cu、Fe、K、Mg、P、Zn、C和N 10种元素含量进行测定和比较。 对大羽藓和毛尖青藓2种苔藓植物内13种元素的测定发现:1)同种苔藓对不同元素的富集能力不同。A1、Ca、K、Mg和P的元素含量在苔藓中的富集较其他元素的要高。2)不同种苔藓植物对同种元素的富集能力不同,毛尖青藓较大羽藓能够监测出更多的元素;对于被检测出的元素,毛尖青藓监测出的累积量大于大羽藓,其中累积量最大的元素是Ca为10 874.286 μg.g-1.year-1,最小的是Cu元素为5.438 μg.g-1.year-1。对05年和07年的平藓、大羽藓、南木藓和厚角絹藓元素含量的测定表明:元素在两年中的积累量是不同的。综合分析表明,苔藓生物监测方法可有效监测景点停车场机动车尾气中排放出的典型元素(如Cu、Pb、Ni、Zn、Cd等)含量,而毛尖青藓较大羽藓能更可靠的监测九寨沟自然遗产地单景点汽车尾气金属元素种类及其排放量。 对4个地区3种苔藓10种元素监测发现:1)Ca、Mg、Zn、K和Cu元素在黄龙地区的含量高于在其它地区的含量;P元素在梦笔山地区的含量为最高;Fe和Al元素在夹金山地区的含量高于在其它地区的含量。2)C元素在其它因素一致的情况下,进行不同年龄间的元素含量比较,结果显示元素含量在各年龄间并不存在明显的差异性;N元素含量与年龄的差异出现在黄龙林下及林窗的塔藓、九寨沟林下的锦丝藓及塔藓和梦笔山的塔藓中,而在锦丝藓中未出现元素含量与年龄的差异性;塔藓能检测出更多的元素种类其含量与年龄间存在显著差异,锦丝藓检测到的元素种类次之;除锦丝藓(锦丝藓在林窗中几乎检测不到元素含量与年龄间的差异性)外,其他两种藓在林窗中能检测出的元素种类大于在林下的检测种类。3)元素含量与生境间存在差异性的元素分别有:黄龙大羽藓中的Ca、P和Mg元素;九寨锦丝藓中的Zn元素;夹金山塔藓中的Al、Fe和Zn元素;梦笔山大羽藓中的Al、Fe和Mg元素及锦丝藓中的Ca元素。4)区域、年龄和生境因素对苔藓植株元素含量均达到了显著水平,但两两之间及三者之间的交互作用由于元素种类的不同存在差异。综合分析表明,苔藓植物中的元素含量受年龄、区域的影响较生境的更大。 The revelation of mosses elements content and its spatiotemporal differences is the scientific foundation of moss monitoring. To determine the feasibility of moss monitoring metal depositions derived from travel bus emiss ions in scenic spot, we collected one year-growth samples of two mosses Brachythecim piligerum and Thuidium cymbifolium with different distance (island center, 120m,1000m ) and different direction (north, south and east) far from parking site island from Yuanshilin Spot at Jiuzhaigou World Nature Heritage in the Western Sichuan of China and determined thirteen element (A1, S, Ca, P, Cu, Fe, K, Mg, Mn, Pb, Ni, Zn, Cd)contents by ICP-AES analysis method. And picked 4 kinds of mosses (Macrothamnium macrocarpu m(Reinw. etHornsch.)Fleisch.,Thuidium cymbifolium,Entodon concinnus (De Not.) Par., Neckera pennata) from the direction PS-3 in 2005 and 2007, determined 13 element contents. Collected 3 kinds of moss (Thuidium cymbifo lium, Actinothuidium Hookeri (Mitt.) and Hyolcomium splendens (Hedw.) from Jiuzhaigou natural heritage, Huanglong natural heritage, Mt. Jiajin and Mt. Mengbi in primeval forest with two habitat (undergrowth and forest gap), determined element contents of A1, Ca, Cu, Fe, K, Mg, P, Zn, C and N. We found that, 1) The elements content are difference in same type of moss. Content of A1, Ca, K, Mg and P are higher than others. 2) While the contents of A1, S, Ca, P, Cu, Fe, K and Zn had significant correlation with the different distances from parking site, the nearer the distance was, the more accumulation was; 2) Comparing to Thuidium cymbifolium, Brachythecium piligerum can test more elements which contents show the significant correlation with distances. And Brachythecium piligerum can have greater element accumulation than Thuidium cymbifolium. The element contents in two years (2005 and 2007) are different. The present study found that moss can reliably bio-indicate metal deposition from traffic emissions in one scenic spot and Brachythecium piligerum is a good moss for bio-indicating element content from traffic emissions at Jiuzhaigou World natural Heritage. Determined the 10 element contents in 4 areas through 3 kinds of moss we found that, 1) Ca, Mg, Zn, K and Cu element content is higher in the Huanglong area than in other areas, The P element content in Mt. Jiajin is higher than other areas, Fe and Al element content is higher in the Mt. Jiajin than in other areas. 2) The content of C had no significant correlation with age. As for N, this significant correlation found in Hyolcomium splendens (Hedw.) with 2 habitat in Huanglong, Actinothuidium Hookeri (Mitt.) and Hyolcomium splendens (Hedw.) with undergrowth in Jiuzhai, Hyolcomium splendens (Hedw.) in Mt. Mengbi. The types of elements which content showt he significant correlation are most in Hyolcomium splendens (Hedw.) and least in Thuidium cymbifolium. Except Actinothuidium Hookeri (Mitt.), the types of elements that content had significant correlation with age in forest gap are more than in undergrowth. 3) The elements which content had significant correlation with habitat are P, Ca and Mg in Thuidium cymbifolium in Huanglong, Zn in Actinothuidium Hookeri (Mitt.) in Jiuzhai, Al, Fe and Zn in Hyolcomium splendens (Hedw.) in Mt. Jiajin, in Mt. Mengbi Al, Fe and Mg in Thuidium cymbifolium and Ca in Actinothuidium Hookeri (Mitt.). 4)The region, the age and the habitat factor has coeffect element content. The correlationship between element contents and the age, the region is closer than habitat.

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采用微波消解、电感耦合高频等离子体原子发射光谱(ICP-AES)的方法,对62份不同小麦品种(系)中锌、铁、铜、钙、钠和钾的含量进行了测定。同时利用红外线品质测定仪对主要品质指标粗蛋白、湿面筋、沉降值进行了测定。结果表明,不同小麦品种(系)中各种矿质元素的含量存在差异,2006年小麦品种中铁含量变幅为18.55-58.19 ug/g,平均为30.83ug/g ,最高与最低的相差39.64ug/g;锌含量变幅为5.70-25.80 ug/g,平均为15.13ug/g ,最高与最低相差20.10ug/g。2008年小麦品种(系)中铁含量变幅为16.68-52.25 ug/g,平均为30.10ug/g,最高与最低相差35.58ug/g;锌含量变幅为12.29-33.47 ug/g,平均为21.11ug/g,最高与最低相差21.18ug/g;钙含量变幅为167.53-348.80ug/g,平均为248.59ug/g,最高与最低相差192.59ug/g;铜含量变幅为2.32-5.83 ug/g,平均为2.98ug/g,最高与最低的相差3.61ug/g;钾含量变幅为1822.71-4414.91 ug/g,平均为2617.87ug/g,最高与最低的相差2634.72ug/g;钠含量变幅为10.25-39.82 ug/g,平均为23.05ug/g,最高与最低的相差29.57ug/g。 两年不同小麦品种(系)中矿质元素的含量分析结果表明:铁、铜、钙、钠和钾含量年际变化不明显,说明小麦对铁、铜、钙、钠和钾的吸收较稳定;锌含量变化较大,可能受环境的影响比较大。分析各矿质元素含量与粗蛋白、湿面筋、沉降值及元素之间的相关关系,结果表明,锌含量与粗蛋白含量呈极显著正相关关系,相关系数为0.317,与湿面筋含量之间呈显著正相关,相关系数达到0.246;铁含量与粗蛋白含量呈显著的正相关关系,相关系数是0.262;铜、钙、钠和钾含量与粗蛋白含量、湿面筋和沉降值之间存在正相关,但不显著,其中钠与沉降值之间为负相关。表明施锌或铁对提高小麦粗蛋白和湿面筋有显著效应,其余矿质元素有促进作用但不明显。 利用RAPD分子标记技术对川育23、41058、川育20及其父母本进行分析,力图从分子水平找到小麦矿质元素含量之间的差异性,琼脂糖电泳结果表明不同的小麦品种(系)间扩增出了差异条带。 以上研究结果,将对筛选“微量营养强化型”小麦新材料,选育“微量营养强化型”小麦新品种奠定基础。 62 different wheat cultivars was digested with HNO3 in a tightly closed vessel heated under micro-wave,then contents of zinc,iron,copper,calcium,sodium and potassium were determined by inductively coupled plasma-atomic emission spectroscopy(ICP-AES).The main indexes of wheat quality such as total protein、wet glu and sedimentation volume were detected by Infratec 1255 Food & Feed Analyzer at the same time.The obtained results showed that variation for all of the mineral elements concentrations among different cultivars were observed .In 2006, the amplitude variation of the iron content was 18.55-58.19 ug/g,the average value was 30.83ug/g,and 39.64ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 5.70-25.8 ug/g,the average value was 15.13ug/g,and 20.10ug/g between the highest-content cultivar and the lowest one.In 2008, the amplitude variation of the iron content was 16.68-52.25 ug/g,the average value was 30.10ug/g,and 35.58ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 12.29-33.47 ug/g,the average value was 21.11ug/g,and 21.18ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the calcium content was 167.53-348.80ug/g,the average value was 248.59ug/g,and 192.59ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the copper content was 2.32-5.83 ug/g,the average value was 2.98ug/g,and 3.61ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the potassium content was 1822.71-4414.91 ug/g,the average value was 2617.87ug/g,and 2634.72ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the sodium content was 10.25-39.82 ug/g,the average value was 23.05ug/g,and 29.57ug/g between the highest-content cultivar and the lowest one. Analysis was made on the annual variation of mineral elements content in different Wheat cultivars ,the result shows:there is no obvious difference of iron ,copper ,sodium、calcium and potassium concentrations in wheat cultivars, suggesting the absorption of the iron, copper, sodium、calcium and potassium by wheat are relatively steady ,but zinc concentrations change obviously ,maybe influenced heavily by environment . The correlation between mineral elements 、mineral elements and total protein、mineral elements and sedimentation volume as well as mineral elements and wet glut were analysed in this paper, the result showed that there was significant positive correlation between zinc content and total protein (the correlation coefficient is 0.317), positive correlation between zinc content and wet glu (the correlation coefficient is 0.246), positive correlation between iron content and total protein (the correlation coefficient is 0.262). there was positive but not obvious correlation between the contents of copper, calcium, sodium or potassium and total protein, wet glut or sedimentation volume,among which was negative correlation between sodium and sedimentation volume.It was indicated zinc or iron fertilization has prominent effects in improving the total protein in wheat, the rest mineral elements have Non- obvious facilitation. The study then forecasted the genetic difference of different wheat by the molecular marker of RAPD in order to find differences in molecular level. Chuanyu23、41058、chuanyu20 as well as their male and female parents were analysed by RAPD markers,Agarose gel electrophoresis of DNA revealed the appearance of differential bands . The above-mentioned results of this study establish the foundation to screening the new materials of wheat of " strengthening type of micro- nutrition ", and to breeding the new wheat cultivars of" strengthening type of micro- nutrition ".

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本研究应用微波消解ICP-AES 法对62 个小麦品种及3 个地区土壤的锌铁硒含量进行了分析测定,发现不同小麦品种中微量元素含量差异很大,姊妹系间也存在差异。含铁量最高与最低的小麦品种铁含量相差29.68mg/kg。含锌量最高与最低的小麦品种锌含量相差46.70 mg/kg。含硒量最高与最低的小麦品种硒含量相差0.056 mg/kg。对不同地点的小麦及土壤中锌铁硒含量进行方差分析,发现双流和西昌两地种植小麦的铁含量和硒含量均有显著差异,西昌和荣县种植的锌含量有显著差异。在3 个地点中双流种植小麦硒含量最高,西昌种植小麦的铁和锌含量最高。 通过对小麦微量元素含量与土壤中微量元素含量进行了相关性分析,结果表明:小麦中的锌铁含量与土壤中的锌铁含量呈显著正相关,土壤中铁与锌含量呈极显著正相关,小麦中铁与锌含量也呈极显著正相关。随着土壤微量元素锌铁的提高,小麦中的锌铁元素含量同时提高,而且小麦对两种元素的吸收互相促进。土壤中的硒含量与锌铁含量呈负相关。小麦中硒含量也与锌铁含量也呈负相关。说明锌和铁与硒互相拮抗。小麦硒含量与土壤硒含量呈正相关,但不显著。表明土壤硒含量可以影响小麦硒含量,但不是决定因素,小麦硒含量与小麦自身因素有关。 对姊妹系G290(高硒含量)和G289(低硒含量)进行抗重金属胁迫和抗旱性实验发现,高硒品种G290的抗逆性优于低硒品种G289。 利用RAPD 技术对7 个姊妹系进行遗传差异分析发现,高硒材料G290出现了特异条带,分别标为1、2、3、4,其他姊妹系品种中未发现特异条带,回收4 条特异条带并连接转化,得到目的片段1、2、3 的重组子,进行测序。NCBI 中结果显示没有找到植物中的同源序列,说明特异序列可能是未发现的基因片段,推测可能与小麦硒含量有关,有待进一步研究。 以上研究结果,对小麦营养研究及功能性小麦的筛选和栽培具有指导作用。 In this study, we determinated the contents of zinc, iron, selenium in 62 wheat cultivars and soil samples of three regions by method of microwave digestion/ ICPAES,found that there was great difference of zinc, iron, selenium contents in different wheat cultivars as well as different sister lines. Iron content difference was 29.68 mg/kg between the highest-iron-content cultivar and the lowest one, and zinc content difference was 46.70 mg/kg , selenium content difference was 0.056 mg/kg. Anova analysis was made on contents of zinc, iron, selenium in wheat and soil samples of different locations, significant differences of Fe and Se contents were found between wheat in Shuangliu and Xichang, significant difference of Zn content was found between wheat in Xichang and Rongxian. Se content in wheat of Shuangliu was highest, Fe and Zn contents in wheat of Xichang were highest. Relativity analysis was made on three trace elements in Wheat and in soil, the result showed that there was significant positive correlation of zinc, iron content between in Wheat and in soil, as well as between Fe and Zn both in wheat and in soil. With the improving of Zn, Fe contents in soil, contents of Zn and Fe in wheat increased and absorption of Zn and Fe in wheat will mutual promote. Negative correlation of Se and Zn contents was found in wheat and soil, but not significant, that meant the antagonism of Se and Zn. Positive correlation of Se content in wheat and soil was found. High selenium content G290 and low selenium content G289 in sister lines were selected for heavy metal stress and drought resistance experiments, the result showed that the resistance of high-selenium-content cultivar was better than low selenium one. Analysis on genetic difference was made by RAPD, and specific bands were selected, marked 1,2,3,4, no more specific bands were found in other sister lines.4 bands were recovered, ligated to T-vector and transformed E.coli. Three recombinant plasmids were obtained and sequenced. NCBI Blast showed there was no homology with other plants. It implied that these fragments probably be new genes and maybe were related to selenium in wheat. It needs further research. This paper would be useful for the study of wheat nutrition as well as selection and cultivation of functional wheat.

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捷安肽素是一种由枯草芽孢杆菌(Bacillus subtilis)ZK 产生的抗真菌多肽。本文以柑桔青霉菌(Penicillium italicum)和绿霉菌(Penicillium digitaum)为供试真菌,研究了捷安肽素的抑菌性能及作用机理,为捷安肽素开发为有效的生物杀菌剂提供理论依据。全文共分两部分:第一部分:捷安肽素对柑桔青霉菌和绿霉菌抑制效果研究。采用琼脂扩散法测定捷安肽素对柑桔青霉菌和绿霉菌的抑菌活性。53.9 µg/mL 捷安肽素对绿霉菌和青霉菌的抑菌圈直径分别为26.7mm 和24.1mm。结果表明捷安肽素能够抑制柑桔青绿霉菌的生长,柑桔绿霉菌比青霉菌对捷安肽素敏感。在柑桔果实上,研究了不同浓度、不同接入时间的捷安肽素对柑桔青霉病和绿霉病的防治效果,并与常用化学杀菌剂抑霉唑、咪鲜胺、甲基硫菌灵和多菌灵作比较。53.9 µg/mL捷安肽素处理柑桔果实,柑桔青霉病和绿霉病发病率分别为5.0 %和5.3 %,比对照低95.0 %和94.7 %;柑桔青霉病和绿霉病的病情指数分别为1.87 和2.18,比对照低73.73 和97.82。结果表明,捷安肽素能够有效地防治柑桔青绿霉病。与对照相比,捷安肽素先于或后于柑桔青绿霉菌接入时,对柑桔青绿霉菌均有抑制作用,但抑制效果随接入间隔时间的增长而降低。第二部分:捷安肽素对绿霉菌作用机理研究。首先在光学显微镜和透射电镜下观察捷安肽素处理后绿霉菌菌丝表面形态结构与菌丝体内超微结构的变化。形态观察发现,捷安肽素处理24h以内,绿霉菌菌丝结构无变化。捷安肽素作用36h后,绿霉菌菌丝不规则缢缩和膨大。48h后,在绿霉菌菌丝顶端、中部、末端的多处细胞均可发生畸形的球状结构,这种畸变结构随处理的延长而增加,致使细胞成为捻珠状。处理72 h后,畸变球形细胞开始断裂离解。处理96h后,镜下几乎无完整菌丝,成单个的球状细胞,部分细胞出现破裂。而对照菌丝表面光滑,结构完整。通过透射电镜观察发现,与对照相比,捷安肽素处理后,绿霉菌细胞壁、细胞膜轮廓模糊不清,细胞质外泄。推测捷安肽素能够使绿霉菌细胞膜通透性发生改变。进一步实验利用紫外-可见分光光度计检测捷安肽素作用后绿霉菌胞外液紫外吸光度的变化,表明捷安肽素作用于绿霉菌菌丝后,细胞内蛋白质、核酸缓慢泄漏。通过Atomscan Advantage单道扫描等离子体发射光谱仪(ICP)测定捷安肽素作用后菌丝体内K+浓度的改变,结果表明捷安肽素作用于柑桔绿霉菌1h内,菌丝体内K+含量迅速下降,为对照绿霉菌K+含量的37.53 %,1 h后菌丝体内K+含量变化趋于平缓。K+的迅速泄漏,以及蛋白质、核酸的泄漏表明捷安肽素通过迅速改变绿霉菌细胞膜通透性,使绿霉菌菌丝生长受到抑制。Jiean-peptide produced by Bacillus subtilis ZK has broad-spectrumresistance to plant pathogens. In this study, we investigated the antifungal propertyand the possible antifungal mechanism of jiean-peptide against two commonphytopathogenic fungi of citrus fruits: blue molds (P. italicum) and green molds (P.digitatum).The paper involved two parts:Part 1 is the study of the antifungal property of jiean-peptide against blue moldsand green molds of citrus fruits. The in vitro inhibition effect of jiean-peptide againstblue molds and green molds was detected by agar diffusion method. The diameters ofinhibition zones of green molds and blue molds are 26.7mm and 24.1mm respectivelyby treating with 53.9 µg/mL jiean-peptide. It shows that jiean-peptide effectivelyinhibits the both phytopathogenic fungi, and it is more effective for inhibiting greenmolds than blue molds. The effectiveness of jiean-peptde to inhibit green molds andblue molds in vivo was investigated compared with four conventional fungicides thatare imazalil, prochloraz, carbendazin and methylthiophanate. The result is that the incidences of the blue mold disease and green mold disease are 5.0 % and 5.3 %, thedisease severities are 1.87 and 2.18 respectively when citrus are inoculated with 53.9µg/ml jiean-peptide. The decay incidences and disease severities were significantlyreduced by treating with jiean-peptide compared with the control. The results indicateJiean-peptide is effective for controlling blue molds and green molds on citrus. Theoptimized inoculation time was also investigated. When inoculated with jiean-peptideat 0 h, 6 h, 12 h, 24 h and 48 h before or after pathogens’ inoculation, Jiean-peptidecan suppress the occurrence of blue molds and green molds compared with the control, but the effect of later inoculation decreases compared with the inoculation at the sametime.In Part 2, we investigated the possible antifungal mechanism against greenmolds of citrus. At first, we observed the exterior morphological changes andultrastructural changes of blue molds under light microscopy (LM) and transmissionelectron microscopy (TEM). Compared with untreated control cells which aregenerally uniform in shape, the appearances of treated hyphae change obviously. Itshows that some cells of hyphae irregularly shrink or enlarge when cultured for 36h.When the treating time of jiean-peptide increases, the aberrance of the hyphaebecomes more obvious, and hyphae exhibit the moniliform appearances. Finally, thereis no intact hypha leaved except only single cells, and some of which appear fractured.By transmission electron microscopy (TEM) observation, we find that the outline ofthe cell wall and the cell membrane of hyphae are blurry, and the cytoplasma oozesout. The observation result under LM and TEM suggests that jiean-peptide mightchange the permeability of the cell membrane. So we conducted further experiment todetect the change of permeability when the cells of blue molds were treated withjiean-peptide. And the effect of jiean-peptide on non-growing cells of blue molds wastested. By the spectrophotometer measurement, we found that compounds with lightabsorption at 260 nm and 280 nm were released and amounts increased within 12 hcompared with the control. Moreover, by the ICP measurement, the leakage of K+occurred immediately in the presence of jiean-peptide within 1 h, but with nearly nofurther change after 1 h. All these results indicate that jiean-peptide could change themembrane permeability of blue molds immediately and result in leaking nucleotides,proteins and K+ from cells.