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The mechanism of electrochemical redox reactions of (tetra-phenylporphinato) managanese(III) perchlorate, (TPP)Mn(III)ClO4, was studied In the presence of chloride anions in dichloroethane solution. It was demonstrated that Mn(II) or Mn (III) centre can be coordinated with only one chloride anion, this result makes an about 100 mV negative shift of half-wave potential of Mn (III)/Mn (II) reduction. An equilibrium constant of 2.2 x 10(4) was determined for the complexation reaction of Cl- and Mn(III) centre.

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在二氯乙烷溶液中,研究了氯离子存在下四苯基卟啉合锰,(TPP)Mn(III)ClO_■,各步电极氧化还原的过程机理,证明了Mn(II),Mn(III)中心都只与一个Cl~-配位,其结果使锰卟啉中心金属Mn(III)/Mn(II)的半波电位负移约100mV,测定了Cl~-与Mn(III)中心的配位反应的平衡常数为2.2×10~4.

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本文描述了气提浓缩仪的设计及操作程序用于对水中痕量挥发性有机物的测定。分析物被气提吸附于TenaxGC柱上,然后直接脱附到毛细管气相色谱柱上进行分析,并用FID或MS鉴定。本文除对色谱条件进行优化外,对气提时间和脱附温度等分析操作条件也进行了研究。检测下限为0.01-0.30PPb,峰面积检测精度优于6.9%,对16种化合物的回收率优于74%。

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本文收集了三峡截流前后长江口海区1988-2007年间十二景landsat TM遥感影像并进行了表层悬浮泥沙含量的反演,定性的描述了长江口海区洪、枯季的表层悬沙扩散外界和高浑浊水域范围的变化趋势,分析了河流泥沙输移入海形态的变化特征及表层悬沙浓度的变化特征。 通过对2002-2004年在长江口滨外区表层悬浮体取样数据的实验室处理,揭示了三峡截流后表层悬沙的分布特征;通过多船同步定点观测捕捉到了长江口河口锋带的位置并分析了河口锋带的动力特征,结果表明:长江口河口锋位于(122o10′E,30o50′N)至(122o20′E,31o00′N)一线附近,在河口锋带位置有着较为强烈的河海相互作用,流速不符合典型的对数流速曲线,河水与海水的相互消长局限于海面以下5m的表层范围,在河口锋面区悬浮泥沙为泥沙流伏在海水之上输运。长江口悬沙体浓度由于三峡蓄水作用表现为下降趋势,悬浮体扩散范围相比截流前向口门后退,长江口滨外区羽状锋带随之向口门后退。 利用二维潮流数值模型较成功地模拟出了每个季度长江河口外的流场情况及河口锋带的发育情况,模拟表明:春、夏、秋三季河口锋带较易出现,且小潮期间发育最好。冬季长江河口海洋动力较强,易于发生海水入侵,尤其是北支;夏季是长江三角洲的主要建设期,锋带作用的存在使得泥沙大部分在锋带的内外区域沉积;春秋两季是平衡期;冬季主要是冲刷的时期。

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对高寒小嵩草草甸冷季草场主要21种植物种群在不同放牧率下优势度、生态位宽度及生态位重叠规律的研究结果表明:1)经过两年的放牧,对照、轻度和中度放牧组的主要优势种均为小嵩草和垂穗披碱草,重度放牧组的主要优势种变成了小嵩草和鹅绒委陵菜;2)尽管枯草期小嵩草和高原早熟禾的适口性较好而被优先采食,但由于它们特有的耐牧、耐践踏等生物学特点,生态位宽度依然很大(0.948,0.901);垂穗披碱草尽管由于适口性和耐践踏性相对较差,但由于其株高优势,生态位宽度依然较大(0.815);青海野青茅和紫羊茅在枯草期由于适口性较好而耐践踏性相对较差,对放牧及由放牧引起的环境变化反应最为敏感,其生态位宽度很窄(0.302,0.416),说明放牧抑制了高大禾草层片的发育,为植株矮小的莎草科牧草和阔叶植物的生长创造了条件;3)鹅绒委陵菜和雪白委陵菜、高山紫菀和柔软紫菀之间生态位重叠的降低,是种间对资源利用上分化的结果,且生态位宽度较大的物种与其它种群间也有较大的生态位重叠,分布于放牧演替系列两个极端的种群间生态位重叠较小,说明物种的分布是既间断又连续的.

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墨引1号(原代号99-22)、墨引2号(原代号99-36)是中国科学院西北高原生物研究所和青海省农业技术推广总站共同承担国家"948"项目即《国际玉米小麦改良中心(CIMMYT)春小麦新品种(系)引进和栽培试验研究》项目,通过引进、定向选育而成的两个春小麦新品种.这两个品种于2000~2003年参加青海省水地春小麦区域试验和生产试验,2004年2月19日通过青海省农作物品种审定委员会审定,分别定名为墨引1号、墨引2号.

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报道了鹅观草属( Roegneria C. Koch) 4 个种的核型,即中华鹅观草,核型为2n = 4x = 28 = 28m( 2SAT) ; 裸穗鹅观草, 核型为2n = 4x = 28 = 24m + 4sm(2SAT) ;缘毛鹅观草,核型为2n = 4x = 28 = 22m + 6sm(2SAT) ;缘穗鹅观草,核型为2n = 4x = 28 = 24m(2SAT) + 4sm。4 个种核型的共征和自征反映了形态划分中共属分种的合理性。尤其通过核型不对称性和相对进化程度的分析,表明中华鹅观草最原始,缘穗鹅观草最进化,裸穗鹅观草和缘毛鹅观草演化居中;狭颖草系高级于缘毛草系。核型不对称性所表示的进化程度似乎与系间颖芒的发生,种间花序的增长变粗、外稃芒的延伸相关。

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Kurki, M. (2006). Causes of a Divided Discipline: Rethinking the Concept of Cause in International Relations theory. Review of International Studies, 32 (2), 189-216. RAE2008

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Aims and objectives: This study represents the first sustained quantitative and qualitative attempt to involve both Republicans and Loyalists in an investigation of the impact of imprisonment and the role of politically motivated former prisoners in the process of conflict transformation in Northern Ireland. The overall aim of the project is to examine the ways in which groups of former prisoners are involved in peace-building and conflict transformation work and to evaluate the constraints and impediments placed upon their activities by the effects of the imprisonment process, politically motivated release and residual criminalisation. In pursuing the evaluation of the role of politically motivated former prisoners working within and without their own communities, the research has six specific objectives: To trace the evolution and development of former prisoner groups; To evaluate the impacts of imprisonment and release on the personal lives of former prisoners; To assess the constraints imposed on former prisoners as agents of change by the residual criminalisation arising from their status; To determine the potential of the former prisoner community in challenging intra-community tensions and evaluate their potential and actual contribution to conflict transformation at the inter-community level; To compare and contrast the effectiveness of Loyalist and Republican former prisoners as agents of change within their own communities; To explore the notion of former prisoners as agents of social and communal transformation within broader political processes through grounding the knowledge and practical experience of the former prisoner community within the broader conceptual context of conflict transformation.

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Very long-term memory for popular music was investigated. Older and younger adults listened to 20-sec excerpts of popular songs drawn from across the 20th century. The subjects gave emotionality and preference ratings and tried to name the title, artist, and year of popularity for each excerpt. They also performed a cued memory test for the lyrics. The older adults' emotionality ratings were highest for songs from their youth; they remembered more about these songs, as well. However, the stimuli failed to cue many autobiographical memories of specific events. Further analyses revealed that the older adults were less likely than the younger adults to retrieve multiple attributes of a song together (i.e., title and artist) and that there was a significant positive correlation between emotion and memory, especially for the older adults. These results have implications for research on long-term memory, as well as on the relationship between emotion and memory.

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La región subhúmeda pampeana presenta una gran heterogeneidad en sus ambientes productivos, que se caracterizan por sus limitaciones en cuanto a la disponibilidad de agua para los cultivos y a su vez, por grandes diferencias en la capacidad de retención de este recurso de los suelos. Los objetivos del presente trabajo fueron estudiar el efecto del ambiente sobre la productividad de la soja (Glycine max (L.) Merrill) en el este de La Pampa y evaluar la eficiencia en el uso del agua (EUA) y el uso consuntivo para cada ambiente. Las evaluaciones fueron llevadas a cabo en suelos Ustisamentes Típicos (Loma) y Haplustoles Énticos (Bajo) ubicados en el establecimiento "Loma Arisca", aledaño a la localidad de Intendente Alvear (La Pampa). Los rendimientos variaron de forma significativa (p menor a 0.05) entre ambientes siendo 3.948 kg/ha para el bajo y 1.275 kg/ha para la loma. La EUA también difirió significativamente entre ambientes (p menor a 0.05) observándose valores de de 6.8 Kg/ha/mm para el bajo y 2.3 kg/ha/mm para la loma. En esta región subhúmeda, el rendimiento de la soja fue afectado positivamente por el ambiente bajo y las diferencias en productividad entre ambientes estuvieron asociadas a la disponibilidad inicial de agua.

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Trabajando en un ambiente de Geometría Dinámica y a partir de actividades que involucran al arbelos de Arquímedes se busca explicitar la formulación de conjeturas y elaborar demostraciones que den cuenta de las conjeturas formuladas, poniendo de relieve la diversidad de resultados obtenidos así como la riqueza de los caminos tomados.

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For the numerical solution of the linearized Euler equations, an optimized computational scheme is considered. It is based on fully staggered (in space and time) regular meshes and on a simple mirroring procedure at the stepwise solid walls. There is no need to define ghost points into the solid ohjects that reflect the sound waves. Test results demonstrate the accuracy of the method that may be used for aeroacoustic problems with complex geometries.

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This presentation will discuss current developments in evacuation modelling and its role in and application to underground applications