外源H_2S对干旱胁迫下小麦旗叶生理特性及籽粒产量的影响

为了探讨外源H2S供体Na HS能否在小麦生育后期提高其抗旱性,在大田盆栽条件下,以豫麦49-198为材料,于小麦挑旗期设置干旱处理,并在叶面喷施不同浓度(0、0.05、0.10 mmol/L)Na HS,测定不同处理下小麦旗叶叶绿素、丙二醛(MDA)、过氧化氢(H2O2)含量及抗氧化酶活性和籽粒产量。结果表明,叶面喷施Na HS可以显著提高干旱胁迫下小麦旗叶叶绿素含量,降低旗叶MDA和H2O2含量,提高旗叶中SOD、POD、CAT活性,进而提高干旱胁迫下小麦单株有效穗数、百粒质量和籽粒产量。其中,干旱胁迫下叶面喷施0.05、0.10 mmol/L Na HS处理小麦籽粒产量分别较不喷施Na HS处理显著提高17.9%、21.4%。综上,外源H2S可以通过提高小麦旗叶的抗氧化酶活性降低MDA等有害物质积累,提高小麦植株的抗旱性,进而增加籽粒产量。     

污泥发酵制氢技术的现状和展望

运用厌氧发酵产氢技术处理污泥制取氢气的研究在国内外已经受到了广泛的关注。本文归纳并分析了厌氧发酵生物制氢的原理、厌氧发酵产氢的途径及其影响因素,并结合国内外研究现状对该技术的应用发展前景进行了探讨。     

外源过氧化氢对枳生长、侧根数和根系碳水化合物含量的影响

研究不同浓度（0~1.25 μM）过氧化氢（H2O2）对枳实生苗生长、根系形态、侧根数、根系葡萄糖、果糖和蔗糖含量的影响。结果表明,与0 μM H2O2比较,只有外源0.25 μM H2O2显著提高了枳株高和叶片数,0.05 μM和0.25 μM H2O2显著提高了根系鲜重,0.05 μM、0.25 μM和1.25 μM H2O2均显著提高根系干重、形态和一级、二级、三级侧根数以及根系果糖、葡萄糖含量。其中,0.25 μM H2O2是促进效应最显著的。     

儿茶素单体EGC对胰脂肪酶的抑制作用及其机理研究

为研究儿茶素单体表没食子儿茶素（Epigallocatechin,EGC）对胰脂肪酶的抑制作用及机制,以干燥绿茶为原料,采用热水提取法、三氯甲烷脱色素和柱层析分离,得到EGC单体。采用扫描电子显微镜、傅里叶红外光谱、核磁共振氢谱对纯化的EGC单体进行结构表征,再通过滴定法研究EGC对胰脂肪酶的抑制作用及类型,然后通过荧光光谱法以及分子对接技术表征了EGC对胰脂肪酶结构的影响。结果表明,EGC以非竞争性方式对胰脂肪酶表现出抑制作用,并且抑制效果随EGC浓度的增加呈持续上升趋势,半抑制浓度为(1.62±0.085) mg·mL^-1。EGC对胰脂肪酶有荧光猝灭作用,可通过分子间氢键和疏水相互作用与酶中的氨基酸残基结合,导致酶的化学结构和空间构象发生变化,从而降低酶活性。EGC主要通过改变胰脂肪酶的化学结构和空间构象来抑制该酶活性,从而达到降血脂功效。     

基于农用氢能的Ag/Co-B/CTAB催化氨硼烷产氢性能研究

氢能作为推动全球能源转型的一种清洁能源,逐渐成为世界能源领域的研究热点,研究发现氢气在农业能源应用、植物信号感知等领域具有重要意义.制备了一种高效催化剂(Ag/Co-B/CTAB)用以催化氨硼烷(AB)水解制氢,通过FTIR、XRD、XPS等技术表征Ag/Co-B/CTAB催化剂的物理化学性质,分析不同温度、催化剂含量...     

壳聚糖基碳量子点的制备、表征及其对过氧化氢的荧光检测研究

为制备可用于分析过氧化氢(H2O2)的荧光传感器,本研究利用壳聚糖与DL-酒石酸为反应前体,水热处理制备了新型氮掺碳量子点(CDs),能够高效、简便地检测食品中的H2O2含量;并采用透射电镜(TEM),以及傅里叶变换红外光谱(FTIR)等方法进行分析表征.结果表明,CDs的荧光量子产率约为5.22％,粒径约为20 nm...     

离子束修饰析氢电极的研究

The article concentrated on the modifying effects of ion beam mixing, ion implanting and ion sputtering of hydrogen evolution electrodes. It was discovered that the four types of electrodes possessed excellent catalytic activity in both acid and alkaline     

麻竹枯萎病的研究——Ⅱ.麻竹枯萎病的抗性生理生化分析

麻竹枯萎病是福建省南平麻竹生产基地一种毁灭性的新病害。经测定,抗冻性强不感染枯萎病的南平品系麻竹与抗冻性弱严重感染枯萎病的漳州品系麻竹,在水分、电导率、酶活性、蔗糖含量及pH值等均存在显著差异。这些差异阐明两个不同品系麻竹抗病性的机理;冻害是诱导枯萎病发生的主要因素,土壤中兼性寄生的半裸镰孢霉(Fusarium Semitectum)是在麻竹遭受严重冻害之后,才能从竹杆基部的节间伤口侵染为害。选用抗寒品种(品系)是防治麻竹枯萎病的根本措施。     

Spatial and temporal variation of reactive oxygen species and antioxidant enzymes in o-hydroxyethylorutin-treated tomato leaves inoculated with Botrytis cinerea

Pretreatment of detached tomato leaves with o -hydroxyethylorutin reduced the percentage leaf area affected, and delayed the appearance of necrosis, following inoculation with conidial suspensions in droplets of the grey mould fungus Botrytis cinerea . o -Hydroxyethylorutin delayed, but did not inhibit, in vitro germination of conidia, although overall percentage germination was reduced compared with water controls. Both the reactive oxygen species (ROS) – superoxide anions and hydrogen peroxide – increased twice as much in o -hydroxyethylorutin-treated leaf tissue 2 and 6 h postinoculation with B. cinerea conidia in tissues under inoculation drops, as well as in surrounding tissues, whereas in plants not pretreated with the compound ROS generation was noticed later, and only in tissues under inoculation drops. Compared with these compounds, changes in the levels of hydroxyl radicals, lipid peroxidation and the activity of the enzymes superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase and catalase were largely unchanged. In stimulating ROS in inoculated tomato tissue, B. cinerea appeared to be affected directly pre- and postinfection, but indirect effects increasing host resistance cannot be excluded.