几种鲜见的《耕织图》

本文主要介绍了南宋梁楷、李嵩，明代仇英、宋宗鲁，清代冷枚、陈枚、何太青以及袖珍型等八种目前比较鲜见的《耕织图》，并分别就其内容作了一些比较和分析，对《耕织图》的发展和演变作了分析。以此作为对《中国古代耕织图》一书的部分读者所提问题的释疑。     

谭新华教授治疗勃起功能障碍经验

谭新华教授对勃起功能障碍的病因病机认识、病证表现、证候分型、治疗方法方面都有独特的见解和心得,认为“房劳伤肾”是本病的基本病因病机;将本病分为肾阳虚衰、肾精亏损、心脾两虚、肝气郁结、惊恐伤肾、瘀血阻络、湿热下注7种基本类型;临床治疗病证结合,随证遣方,随症用药,中西结合,多法活用。     

不同类型茶园捕食性天敌群落相似性研究

采用群落种组成相似性分析、群落组成相似性分析和群落特征相似性分析3种方法,研究了祁红产区等高茶园、平地茶园和坡地茶园3种茶园类型及春茶、夏茶和秋茶3个生育期捕食性天敌群落的相似性。结果表明,群落种组成相似性平均水平的排序为不同类型茶园相同生育期>不同类型茶园不同生育期>同一类型茶园不同生育期>同一类型茶园相邻生育期。坡地茶园秋茶、平地茶园夏茶和秋茶以及等高茶园秋茶的群落组成最为相似;而平地茶园和坡地茶园春茶次之。等高茶园和平地茶园春茶的群落特征最相似,其次为3种类型茶园秋茶及平地茶园夏茶。     

Synchrotron X-ray Diffraction Measurements of Single-Crystal Hydrogen to 26.5 Gigapascals

The crystal structure and equation of state of solid hydrogen have been determined directly to 26.5 gigapascals at room temperature by new synchrotron x-ray diffraction techniques. Solid hydrogen remains in the hexagonal close-packed structure under these pressure-temperature conditions and exhibits increasing structural anisotropy with pressure. The pressure-volume curve determined from the x-ray data represents the most accurate experimental measurement of the equation of state to date in this pressure range. The results remove the discrepancy between earlier indirect determinations and provide a new experimental constraint on the molecular-to-atomic transition predicted at higher pressures.     

发枝素对国光苹果萌芽发枝效果的研究

萌芽力和成枝力低是国光苹果始果晚的限制因素,目前常规的农业技术措施尚不能解决这一问题。本研究在河北固安、霸县两地8年生同龄苹果园中同时进行,用拉丁方等田间设计方法,安排了3个因素(时期、部位、芽数)、9个水平的发枝素处理试验。1987年6月初对处理的162株树、11340个芽所得的实测数据,用数量化理论Ⅰ分析得出:(1)发枝素的使用对1年生枝的萌芽力和成枝力有显著效果。(2)萌芽前后不同时期应用发枝素有同等效果。(3)不同涂抹芽量在所用数量范围内不影响萌芽力。(4)在枝条的下部涂抹萌发效果最好。这些结果对萌芽力和成枝力差的国光等品种具有重要的实践意义。     

Sound velocities in dense hydrogen and the interior of jupiter

Sound velocities in fluid and crystalline hydrogen were measured under pressure to 24 gigapascals by Brillouin spectroscopy in the diamond anvil cell. The results provide constraints on the intermolecular interactions of dense hydrogen and are used to construct an intermolecular potential consistent with all available data. Fluid perturbation theory calculations with the potential indicate that sound velocities in hydrogen at conditions of the molecular layer of the Jovian planets are lower than previously believed. Jovian models consistent with the present results remain discrepant with recent free oscillation spectra of the planet by 15 percent. The effect of changing interior temperatures, the metallic phase transition depth, and the fraction of high atomic number material on Jovian oscillation frequencies is also investigated with the Brillouin equation of state. The present data place strong constraints on sound velocities in the Jovian molecular layer and provide an improved basis for interpreting possible Jovian oscillations.     

Outlier identification of soil phosphorus and its implication for spatial structure modeling

Outliers are classified as global outliers and spatial outliers. Up to now, there is little information about the outliers especially the spatial outliers and their influence on the spatial structure modeling of soil properties. A total of 537 soil samples were collected based on a 30 × 30 m grid in a permanent dairy farm in southeast Ireland. Graphic methods of histogram and box plot combined with Moran’s I were applied to detect the outliers of soil phosphorus (P). Sixteen outliers (5 global outliers and 11 spatial outliers) of soil P were found in the study area. Compared to the raw data, the data with global outliers excluded always had the larger global Moran’s I value indicating a stronger spatial autocorrelation. Clear spatial clusters (High–High and Low–Low clusters) were observed based on local Moran’s I. The High–High spatial clusters were located around the main farm yard and near the traffic route due to more intensive management by farmers. The Low–Low spatial clusters were mainly close to the river. For these areas, P fertilizer or slurry should be applied for healthy grass growth. The dataset with outliers excluded had a reliable semi-variogram model with a low nugget/sill ratio (32.4 %), which was closed to its corresponding transformed data (30.5 %). The cross-validation results revealed that the dataset without outliers had the strongest linear regression model (r = 0.768), indicating that the outliers played an important role in the spatial structure modeling.     

山核桃外果皮黄酮提取与纯化

采用有机溶剂萃取法提取山核桃外果皮黄酮化合物,通过单因素和正交试验确定了最佳工艺参数.结果表明,提取溶剂为体积分数70％乙醇、提取时间4h、提取温度60℃、液料比15 mL/g条件下得黄酮化合物最高提取率为1.14％.采用硅胶色谱柱层析法纯化黄酮化合物,在液固比3 mL/g的条件下,体积分数70％乙醇以2 mL/min...     

甲虫声通讯的研究进展

声通讯是甲虫的重要通讯方式,在种内交流、求偶、逃避敌害等方面具有重要作用。关于甲虫声通讯的研究早在一百多年前就已经展开,主要集中在形态结构、声信号的产生和功能、声行为以及应用等方面。本文就国内外关于甲虫声通讯的研究及应用进行综述。     

滑道分钵轮式栽植器的试验研究

对滑道分钵轮式栽植器的结构、工作过程、钵体在滑道不同部位的运动状态和受力情况进行了分析，并对该栽植器的工作稳定性和立苗率进行了正交和单因素的试验分析。影响栽植器立苗率的因素顺序是钵体含水率，钵体侧面形状和滑道倾角。影响栽植器立苗率的主次因素，有覆盖物时是：滑道尾部的离地高度、机具前进速度、滑道倾角；无覆盖物时是：滑道尾部的离地高度、滑道倾角、机具前进速度。找出了栽植器工作稳定性的影响因素及其最佳值和对立苗率影响的因素及其最佳值。