室内花卉种植的新方法无土栽培研究

在1989年至1993年间,科研小组用无土栽培方法试验栽培了12科60种室内花卉,结果发现除少数品种在液培环境下度夏、过冬困难外,许多种如:绿萝、龟背竹、吊兰、木麒麟、玉晴蜓、花叶豆瓣绿、虎耳、鸭趾草等能适应改变了的环境,长势良好,具有推广价值。试验还从筛选营养液方面着手,选用四种不同配方进行栽培比较。结果表明:每种花卉的适应性不同广谱的营养液具有浓度小,氮素含量较低,相对的Ca~(2+)、Mg~(2+)、SO_4~(2-)等较丰富的特点。     

电导法测定298K时NdCl3在DMF和H2O中的活度系数

应用电导法在298K时测定了稀土氯化盐NdCl3在混合溶剂(DMF-H2O)中的电导率;利用公式计算了NdCl3的摩尔电导率;应用Kohlraush经验规则,使用Origin软件进行线性拟合,外推得到298K时NdCl3在混合溶剂(DMF-H2O)中的无限稀释摩尔电导率λ0 =300.01 (S*cm2 *mol-1);应用Debye-Hücker 和Osager-Falkenhangen公式计算了NdCl3在混合溶剂(DMF-H2O)中的活度系数,并讨论了在298K时浓度对稀土盐NdCl3溶液活度系数的影响,随稀土氯化盐溶液浓度的增加,稀土盐溶液的活度系数降低.     

钙钛矿型系列LaMnO_(3 λ)的初步研究

合成了系列稀土复合氧化物LaMnO_(3 λ).并对其进行了结构、电阻率及对二甲苯燃烧的催化活性测定。初步解释了结构与性能的关系。     

Preparation and Water—Gas Shift Catalytic Activities of the Perovs—kite Type Complex Oxide La1—xCexFeO3

Thewater gasshiftreaction (WGSR)isanimpor tantstepinmanyindustrialprocesses,includingammoni aandhydrogenproduction .Itisusuallyassistedbysev eralcatalysts ,oneofwhichisiron basedshiftcatalystwithatypicalcompositionof 74 .2 %Fe2 O3,10 .0 %Cr2 O3,0 .2 %MgO ,0 .5 %K2 Oandbalancevolatiles[1] .Obviously ,chromiaasthemainadditivecanbefoundinalmostallofiron basedhightemperaturewater gasshiftcatalysts.ThehexavalentchromiuminCrO3,thepre cursorofchromiainFe Crseriescatalysts ,isakindofveryharmfuls…     

从评价理论的角度重探赛珍珠小说《大地》的“土地”主题

通过例析叙述者、男主人公和女主人公对“土地”的评价意义项,可以发现,小说运用了不同类别的评价项,如鉴赏的价值、反映,情感的意愿、高兴、安全,判断的妥当.这些态度意义既有积极的,也有消极的,既有词汇层面的,也有小句层面的,它们共同构成一个评价意义“群”,在探讨小说主题构建方面发挥了很好的阐释作用.从评价系统对小说主题的试析为运用语言学理论分析和解释文学作品提供了一个颇有意义的研究角度.     

Book Nomenclature

No abstract available for this article.     

鄂尔多斯盆地镇北地区延长组长7沉积期物源分析

收集前人研究成果,结合薄片鉴定、重矿物分析、稀土元素及地震等资料,对鄂尔多斯盆地延长组长7沉积期物源进行分析.结果表明：镇北地区延长组长7物源来自盆地西部和西南方向,其中西南物源为主要物源区,主要岩性为变质岩、中酸性岩浆岩;西部方向仅为沉积区提供白云岩等碳酸盐岩碎屑.     

Re-Discovering a Roman Wall Painting at Harvard: New Research on a Fragment from the Villa at Boscotrecase

ABSTRACT

This article presents historical and scientific analysis, as well as the conservation treatment of a newly rediscovered Roman wall painting fragment, now in the collection of the Harvard Art Museums. Although the piece has not previously been published, it was among a group of fragments removed from a Roman villa near Boscotrecase in southern Italy, an area that has been key to the study of Roman wall painting and other decoration. Technical imaging confirms the use of painting techniques consistent with other high-quality paintings in the area. Materials analysis revealed a palette consistent with published findings of Roman wall paintings, including abundant use of Egyptian blue and green earth. Of interest was the use of Egyptian blue as an optical brightener in select white passages. Despite the high quality of the painting, no cinnabar was present, and all red passages were achieved using hematite. Multiple different white minerals were identified including calcite, aragonite, and gypsum. The widespread presence of gypsum is unusual and may point to alteration.     

Google Earth在《遥感原理与方法》教学中的应用

Google Earth作为一门新技术,在多种领域中得到广泛应用.介绍了在《遥感原理与方法》课程教学过程中,Google Earth在影像的直观性、遥感影像的大气校正、遥感影像的几何校正、遥感影像的像点位移以及遥感应用等方面的作用.教学结果表明,Google Earth能够激发学生的学习兴趣,提高教学效果.     

Single-phase earth fault current distribution between optical fiber composite overhead ground wire and ordinary ground wire in transmission system

It is important for the safety of transmission system to accurately calculate single-phase earth fault current distribution. Features of double sided elimination method were illustrated. Quantitative calculation of single-phase earth fault current distribution and case verification were accomplished by using the loop method. Influences of some factors, such as single-phase earth fault location and ground resistance of poles, on short-circuit current distribution were discussed. Results show that: 1) results of the loop method conform to those of double sided elimination method; 2) the fault location hardly influences macro-distribution of short-circuit current. However, current near fault location is evidently influenced; and 3) the short-circuit current distribution is not so sensitive to the ground resistance of poles.