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关键词： 植物药   中药   铁皮枫斗晶   抗疲劳作用   检验  

摘要： 铁皮枫斗是石斛的一种,石斛分为铁皮、霍山、金钗、环草、黄草、马鞭等品种,以铁皮石斛最为珍稀,被道家称为中华九大仙草之首.称它有强阴益精、厚肠胃、补内绝不足、轻身延年的功效.铁皮枫斗晶是以铁皮枫斗为主要原料制成的中药产品.为证实它的抗疲劳作用,我们参照[1],进行了本次实验观察.

关键词： Management   Precision   Features  

摘要： We assessed the precision of visual estimates of vegetation and substrate along transects in 15 shallow, natural Nebraska lakes. Vegetation type (submergent or emergent), vegetation density (sparse, moderate, or dense), and substrate composition (percentage sand, muck, and clay;to the nearest 10%) were estimated at 25-70 sampling sites per lake by two independent observers. Observer agreement for vegetation type was 92%. Agreement ranged from 62.5% to 90.1% for substrate composition. Agreement was also high (72%) for vegetation density estimates. The relatively high agreement between estimates was likely attributable to the homogeneity of the lake habitats. Nearly 90% of the substrate sites were classified as 0% clay, and over 68% as either 0% or 100% sand. When habitats were homogeneous, less than 40 sampling sites per lake were required for 95% confidence that habitat composition was within 10% of the true mean, and over 100 sites were required when habitats were heterogeneous. Our results suggest that relatively high precision is attainable for vegetation and substrate mapping in shallow, natural lakes.

关键词： circumstellar matter   stars : fundamental parameters   stars : pre-main-sequence   infrared : stars  

摘要： We studied a sample of 27 T Tauri stars (TTs) showing a weak Halpha line, selected from the Pico dos Dias Survey, a search for young stellar objects. A model to fit the spectral energy distribution is used in order to reproduce their observed infrared excess and to evaluate the individual contribution of the circumstellar components (dust disc and/or envelope) to the total emitted flux. The objects were separated into different categories of young stars, searching for an agreement with an evolutionary sequence. The classification is based on the stellar characteristics as spectral type;equivalent width of the Li 670.8-nm line;optical and X-ray properties;and infrared excess. We conclude that only 41 per cent of our sample actually correspond to weak TTs, and the remaining objects are mainly classical TTs or young main-sequence stars. Most of the stars have a near-infrared index typical of Class II objects and show an important fraction of the observed emission (similar to30 per cent) being generated by the circumstellar material.

关键词： 加盟者   处理方法   特许经营   中国   被特许人   违约行为   财务制度   收费标准   保证金  

关键词： E-检验   抗菌药   多重耐药性   铜绿假单胞菌   作用  

关键词： 合同形式   规则   功能  

摘要： 合同形式要求规则具有两种功能 ,一是证据功能 ,一是强调当事人意思表示的严肃性。当今各国因各自的立法目的不同而在这两种功能上各有侧重。我国立法有关合同形式要求规则的规定存在不确定性 ,应根据其功能从不同的方面加以完善。

关键词： 无权处分   无权处分行为   债权行为   处分行为   《合同法》  

摘要： 如何理解《合同法》第 5 1条 ,是合同法颁行后民法学界讨论最多的问题之一。学者之间的不同见解乃因所持解释前设不同 ,即对无权处分制度是通过债权行为 ,还是通过物权行为进行规制有不同立场。通过利益调和功能的比较 ,以及债权行为无效导致法律体系解释困境的说明 ,可以认为无论债权行为规制形式的具体方案如何设计都难以达成妥当结果。债权行为不因欠缺处分权而确定有效不会过度保护买受人 ,能够达成最佳制度效果。因而 ,物权行为规制形式具有合理性。鉴于我国现行法并不认可处分行为独立性 ,所以不宜认为无权处分行为包括债权行为的履行行为。在我国现行法背景下《合同法》第 5 1条仅调整无需履行而直接发生权利变动效果的合同关系 ,具体类型主要为一般动产抵押合同与质押合同 ,适用机会极其有限。

关键词： 大学生   体质   综合评价   样品分类问题   研究  

摘要： 学生的体质状况如何 ,一直是国家所关注的问题。我国从 1979年至今 ,基本上是每隔 5年进行一次全国性的体质调研 ,这对掌握青少年的身体发育规律、提高身体素质、促进学校体育、卫生等工作的开展均具有十分重要的意义。对学生体质问题的研究 ,涉及到方方面面 ,内容非常丰富 ,本文仅就样品分类进行研究、探讨。不少学者对这一问题进行了研究 ,取得了一些可喜的研究成果。笔者曾立项进行系统研究 ,用过逐步判别、对应分析方法 ,研究结果较为理想 ,本文是该问题的系列研究之一。对样品的分类 ,若是单项指标 ,或是指标不多 ,用离差等方法可以很好地解决 ,并不复杂。但指标较多时 ,由于每个样品各指标发展的不均衡

关键词： 无人售票公交   法律思考   合同法   中国   '不设找零'问题   客运服务合同   乘客   承运人  

关键词： degradation of materials   impingement   Stellite   Soil erosion   Synergism   Electrochemical Techniques   electrochemical corrosion   Corrosion rate   Corrosion  

摘要： In this paper aspects of the corrosion behaviour of two materials (Co-base Stellite X-40 and austenitic cast iron BS 3468 S2W) under aggressive slurry erosion conditions are considered. Electrochemical techniques are used to assess the rate of corrosion in impingement conditions. The material degradation has been separated into components of mechanical erosion, electrochemical corrosion and interactive effects. It has been shown that the erosion significantly enhances the corrosion rate of both materials and has the effect of moving Stellite X-40 from a passive to an active corrosion regime. However, in terms of the magnitude of the material loss component the effect of corrosion on erosion (often referred to as synergy) is a much more prominent feature for both materials. (C) 2002 Elsevier Science Ltd. All rights reserved.