洋河大曲中螺甾醇健康功能因子研究

白酒是我国最重要的传统发酵食品之一,在世界范围内享有很高的声誉。曲药被称为酒之骨,决定了白酒的风格和品质,对白酒酿造起着举足轻重的作用。目前,主要采用顶空-固相微萃取与气质联用的方法研究大曲中低沸点香味物质,对大曲中高沸点难挥发成分研究鲜有报道。本研究以洋河酒厂提供的大曲为材料,利用95%vol乙醇进行提取,结合正相硅胶、反相硅胶、Sephadex LH-20等多种色谱技术,从大曲中分离得到6个螺甾醇类化合物,应用核磁共振、质谱等波谱技术分别将其鉴定为sarsasapogenin(1)、7α-hydroxysarsasapogenin(2)、yamogenin(3)、diosgenin(4)、neotigogenin(5)和tigogenin(6)。本研究首次从洋河大曲中发现了具有广泛生理活性的螺甾醇类小分子,为揭示中国白酒的健康功能因子奠定了基础

Guilspare(R)施用量对土壤蒸发和水盐垂直分布的影响/Effects of Guilspare(R) requirement on soil evaporation and the vertical distribution of soil water and salt[J]

塔里木沙漠公路防护林生态工程全长436 km,位于极端干旱的塔克拉玛干沙漠,造林树种以抗逆性较强的沙拐枣属(CalligonumL.)、柽柳属(Tamarix L.)、梭梭属(Haloxylon Bunge)等优良防风固沙灌木为主,防护林植物的蒸腾耗水和灌溉管理是防护林可持续的核心问题.为探求适合塔里木沙漠公路防护林的节水技术,利用微型蒸渗仪研究了塔克拉玛干沙漠腹地咸水灌溉条件下Guilspare(R)(浓度1.5％ v/v)施用量对土壤蒸发和水盐垂直分布的影响.结果表明:(1)Guilspare(R)对土壤蒸发有显著影响,其施用量与累积蒸发量间呈对数关系.当施用量小于4.0 L/m2时,土壤日蒸发量在试验初期均表现为对照组(CK)大于处理组,试验中后期却相反；当施用量大于4.0 L/m2时,日蒸发量始终小于CK.(2)Guilspare(R)施用量为6.0 L/m2的抑制效率最大,与其他处理(除7.0 L/m2)间差异达到显著水平(p＜0.05).(3)施用Guilspare(R)对土壤蒸发第一阶段的蒸发强度有明显的减弱作用,其减弱程度与施用量的大小有密切关系,当施用量为6.0 L/m2时,蒸发强度最弱.(4)相同初始含水量条件下,表层土壤含水量和土壤浸提液电导率(除7.0 L/m2)均随着施用量的增大而变小；其他土层(除10～14 cm),两者均随着施用量的增大而变大

矿粮复合区土地生态安全评价——以焦作市为例/Evaluation of eco-security of land for the overlapped areas of crop and mineral production: A case of Jiaozuo City[J]

应用PSR模型构建焦作市矿粮复合区土地生态安全评价指标体系,通过AHP法与熵权法相结合确定24个评价指标的权重,对其2006-2010年的土地生态安全状况进行动态评价与分析,旨在揭示该区域近年来的土地生态安全状况,提出实现其土地可持续利用的建议.结果表明:其土地生态安全综合指数总体呈现先短期轻微下降后又逐年回升的趋势;5a内其安全水平先后经历了较不安全、临界安全、较安全3个等级;状态与响应指标与土地生态安全状况的相关性密切,对环境胁迫的恢复力起重要作用,且在维护和改善土地生态安全状况上的作用不断增强;植被因素对土地生态安全的正作用最明显,生态用地比例等4项指标在土地生态安全评价中的地位相对较重要;主控生态安全的因子越多,生态状况越好;未来3a,其生态状况有继续提升的趋势.实现土地可持续利用须从不同方面通过多种手段进行.该研究为实现区域农业生产和工矿建设等经济活动与土地资源和生态环境保护之间的协调发展提供决策依据

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies