2,2’-联吡啶基嘧啶桥连Cr配合物的电子结构及光谱性质的理论研究

以密度泛函和含时密度泛函为理论基础,通过Gaussion03程序,应用密度泛函中的B3LYP方法,在6-31G（d）基组下,对2,2’-联吡啶基嘧啶桥连Cr配合物的电子结构及光谱性质进行了系统的量子化学理论研究.同时,比较了配合物的几何构型、红外光谱和电子吸收光谱.该研究对有关联吡啶基嘧啶桥连Cr配合物的开发与利用有一定的促进作用.     

B型烟粉虱危害对烟草叶片光系统II的影响

【目的】研究B型烟粉虱取食危害对烟草光系统II的影响,为明确烟粉虱对寄主植物光合作用的影响机制提供依据。【方法】通过测定烟草叶片叶绿素荧光快速诱导曲线,使用JIP-test分析技术进行参数分析,研究B型烟粉虱危害烟草后对烟草的局部虫体叶和系统叶光系统II（PSII）的影响。【结果】B型烟粉虱危害烟草后虫体叶和系统叶上的最大光化学效率（φpo）和光化学性能指数（PIABS）与对照相比均明显升高（P＜0.05）,表明处理烟草植株的局部叶和系统叶的原初光化学反应受到较大的伤害。B型烟粉虱危害烟草后虫体叶和系统叶PSII反应中心的电子传递均受阻,放氧复合体受到严重破坏。B型烟粉虱危害烟草后系统叶的单位反应中心吸收的能量（ABS/RC）和单位反应中心热耗散掉的能量（DIo/RC）增加,单位反应中心捕获的能量（TRo/RC）下降;B型烟粉虱危害的虫体叶中ABC/RC没有变化,DIo/RC增加,TRo/RC 下降。B型烟粉虱危害烟草后虫体叶和系统叶的单位面积反应中心数量（RC/CS）均明显降低（P＜0.05）,而光系统PSⅡ反应中心的关闭程度（1-qP）却明显升高,分别较各自对照升高了69.83%和142.58%（P＜0.05）。【结论】B型烟粉虱的危害严重影响了烟草叶片的光系统Ⅱ（PSII）,主要是由于PSII反应中心的失活和关闭以及对PSII电子传递的抑制,电子传递中受抑制的位点包括放氧复合体和QA到QB间的电子传递过程,同时B型烟粉虱危害影响了烟草叶片光系统的能量流动,且烟粉虱对烟草叶片PSII的影响具有系统传导性。     

过渡金属多核化合物的磁交换作用

利用简单的数学模型推导了包含以第一过渡金属为主的2-5核簇合物的磁公式,一些数学上的简单处理为磁化学研究领域的初学者提供了可借鉴的方法。     

原子吸收法测定棉株体内铜元素的含量

用原子吸收分光光度法分别测定了喷施氨基酸铜和喷施清水后,接种棉花黄萎病菌的感病棉株的根、茎、叶中铜元素的含量。结果表明:喷施氨基酸铜后,接种棉花黄萎病的感病棉株的根、茎、叶中的铜元素的含量明显高于喷施清水的对照棉株。     

紫甘蓝花色苷及其复合体的抗炎活性研究

为了探究紫甘蓝花色苷—3-二糖-5-D-吡喃葡糖苷矢车菊素(cyanidin-3-diglcoside-5-glcoside,Cy)及其复合体对鼠源单核-巨噬细胞RAW264.7的抗炎活性,首先采用紫甘蓝花色苷碱水解产物中的Cy为原料,模拟天然蓝花中结构相对稳定的花色苷复合体存在形式,与芦丁(rutin)及2种不同金属离子(Mg~(2+)和Fe~(3+))构建5种Cy复合体;然后通过建立脂多糖(LPS)诱导的鼠源单核-巨噬细胞RAW264.7炎症模型,评价Cy复合体构建前后对Cy抗炎活性的影响。结果表明,Cy可以显著性抑制RAW264.7细胞上清液中NO释放及细胞内炎症相关基因iNOS、IL-1β、IL-6和TNF-α的mRNA的表达(P0.05)。在构建的复合体中,与Cy相比,Cy-Fe~(3+)、Cy-rutin-Fe~(3+)、Cy-Mg~(2+)和Cy-rutin-Mg~(2+)复合体的抗炎活性均显著提高(P0.05)。其中,Cy-Mg~(2+)和Cy-rutinMg~(2+)复合体的抗炎活性高于Cy-Fe~(3+)和Cy-rutin-Fe~(3+)复合体,而Cy-Mg~(2+)复合体的抗炎活性最强。由这些结果可以得出Cy及其复合体均具有显著的抗炎活性,且Cy复合体的抗炎活性高于Cy。Cy复合体有望开发成为一种新型食品添加剂,辅助干预炎症反应及其引起的相关疾病。     

叶面喷施氨基酸锌复合物对水稻产量性状和锌吸收的影响

通过2012年和2013年的盆栽试验,比较了氨基酸锌复合物和硫酸锌对水稻产量性状和锌吸收的影响。结果表明,与施用ZnSO_4相比,在水稻开花期进行叶面喷施氨基酸锌复合物可提高稻谷产量和秸秆产量,最高可达14.54%和10.40%,可使水稻灌浆粒数和千粒重最高增加11.28%和8.92%。试验结果还表明,氨基酸锌复合物在促进水稻锌吸收方面具有积极作用。在2012年试验中,叶面喷施精氨酸锌复合物、甘氨酸锌复合物和谷氨酰胺锌复合物处理水稻的锌表观利用率分别是20.88%、16.26%和19.34%;而ZnSO_4处理的锌表观利用率仅增加8.89%。2013年试验结果与2012年的结果相一致。因此,氨基酸锌复合物是一种更有效的锌肥。     

Effects of monoglycerides on pasting properties of wheat starch after repeated heating and cooling

The effects of repeated heating and cooling on the properties of pastes prepared from a commercial wheat starch (Triticum aestivum L.) with added monoglycerides were studied using a Rapid Visco Analyser (RVA). The nanostructure of the freeze-dried pastes was determined by X-ray diffraction and small-angle X-ray scattering. Pastes prepared from the wheat starch alone, or from the starch mixed with tripalmitin, which does not form complexes with starch, produced regular viscosity profiles in the RVA when subjected to multiple heat-cool cycles. In comparison, the effects of adding monoglycerides (or monoacylglycerols) depended on the chain length and saturation of the fatty acid of the monoglyceride. Repeated heat-cool cycles in the RVA of the starch with different monoglycerides induced the formation of complexes of varying stability that influenced the viscosity trace of the paste during multiple heating and cooling cycles. Small-angle X-ray scattering in combination with X-ray diffraction proved useful in describing the nanostructural changes in the RVA pastes induced by monoglycerides and temperature cycling. The results indicate that the functional properties of starch pastes may be manipulated through the strategic selection of an added monoglyceride.     

长株潭城市群低碳交通发展探究

全球变暖趋势进一步加剧,低碳发展模式已成为世界共识。交通业作为能源消耗主要部门及温室气体排放的重要来源,必然要走低碳化发展道路。分析长株潭城市群交通发展存在的问题,提出要优化交通体系结构、推动低碳交通技术的创新、引导居民健康出行、加强国际间交流与合作等发展对策,最终实现城市交通的低碳发展。     

Release and mobility of polycyclic aromatic hydrocarbons and iron‐cyanide complexes in contaminated soil

Export of organic and inorganic pollutants from the unsaturated zone of manufactured gas plant (MGP) sites may endanger groundwater quality. The release and mobility of polycyclic aromatic hydrocarbons (PAH) and iron‐cyanide complexes (FeCN) in soils from a former MGP site were studied in column and batch experiments. The unsaturated column experiment involved two parts. (1) The development of steady‐state effluent concentrations was studied under constant irrigation. (2) Rate‐limited contaminant release was studied by the system's response to flow interruption. Transport data were supplemented by a sequential batch‐desorption experiment. During constant irrigation the initial concentrations of total PAH and FeCN, but also the concentration of dissolved organic carbon (DOC) were higher than the steady state level, indicating that a specific fraction of the DOC and the contaminants was readily mobilized. Cyanide reached a constant effluent concentration after seven pore volumes (pvs), whereas equilibration of effluent PAH took 20 pvs. After flow interruption, rate‐limited release of DOC, PAH, and FeCN was observed by increased effluent concentrations. Comparison of FeCN levels with theoretical equilibrium concentrations indicated that in addition to the dissolution of iron(II)ferrocyanide (Berlin Blue), Fe₄[Fe(CN)₆]₃, other cyanide‐species may control the release and such the mobility of FeCN. This was confirmed by decreasing FeCN concentrations during sequential batch extractions. Due to rate‐limited release, seepage water concentrations of DOC, PAH, and FeCN in alkaline MGP soils are influenced by the flow regime. Experiments performed at continuous irrigation may therefore severely underestimate the release of PAH and FeCN under field conditions. The effect of DOC on the release and mobility of PAH and FeCN under transient conditions has to be further investigated.