不同地区黄精氨基酸特征分析及聚类分析

为研究不同地区黄精差异性和相似性,运用化学计量学手段对不同地区黄精氨基酸含量进行特征分析和聚类分析。通过主成分分析对不同地区黄精进行综合排名,验证了氨基酸含量与黄精药用、保健价值的相关性;运用聚类分析对不同地区黄精进行聚类,了解不同地区黄精之间的相似性。为黄精的鉴定和综合开发利用提供理论基础和科学依据。     

宁夏黄精中黄精多糖的提取、分离和测定

应用分光光度法对宁夏不同产地黄精中的黄精多糖进行了测定，为宁夏黄精药材的质量评价提供了方法依据和科学依据     

宁夏黄精中黄精多糖的提了以,分离和测定

应用分光光度法对宁夏不同产地黄精中的黄精多糖进行了测定，为宁夏黄精药 的质量评价提供了方法依据科学依据。     

九华黄精高产栽培技术研究进展

一、引言 九华黄精为多年生草本植物。属药食兼用的大宗药材。《中国药典》规定黄精是以百合科黄精属植物黄精、滇黄精、多花黄精的干燥根茎人药。九华黄精在九华山地区生长范围较广,阴湿山坡和沟谷处较常见。九华山地区的黄精品种为多花黄精,云南、贵州、浙江、山东也有此品种分布,但药材质量都不如九华山地区。为突出其地方特色,取名为九华黄精。     

黄精多糖抗衰老作用及其食品应用研究进展*

从衰老的定义和衰老学说中的自由基学说、端粒学说、线粒体DNA损伤学说、神经内分泌学说角度出发,综述了黄精多糖在清除自由基、增强端粒酶活性、改善线粒体能量代谢、改善神经内分泌功能等方面的作用机理,总结了黄精多糖的提取方法以及在健康食品和日常膳食的研发和应用进展,展望了黄精及黄精多糖的未来研发方向,指出黄精必将成为人们健康生活不可或缺的一部分。     

中药黄精的研究和开发利用途径

黄精是传统医学上长期使用的具有滋补强身、延缓衰老作用的食疗中药。就国内对黄精的药理作用和化学成分方面的研究进行了探讨，指出了黄精资源开发利用的主要途径。     

经济植物黄精Polygonatum Mill的开发和利用

黄精属于百合科,黄精属的植物,其块根内含有大量的淀粉、糖类、沾液质、维生素及多种微量元素,具有滋补阴血、滋养脾胃及润肺的功能,自古被中医、藏医所利用。西藏是我国黄精资源的主要产区之一,据研究区内共有7种黄精。即:轮叶黄精Polyonatum Verticillatum(L)ALL. 点花黄精Polygonatum Punctatum Royle ex Kunth. 独花黄精Polygonatum hookvi Baker. 对叶黄精Polygonatum oppositifolium(Wall)Royle. 三脉黄精Polygonatum griffithii Baker. 卷叶黄精Pobygonatum cirrhifolium(wall)Royle. 棒丝黄精Polygonatum cathcartii Baker等7种,广泛分布于西藏的东部、东南部地区。 近年来,黄精不仅作为药用,还研制出了饮料,食品添加剂,美容剂等系列产品,西藏黄精属的种类多、分布广、储量大、具有一定的开发前景。     

略阳县黄精高效生态种植技术

黄精药食两用，市场前景好，野生资源面临枯竭。利用山区林地和退耕还林地种植黄精具有显著地经济、生态和社会效益。本文在实践的基础上，从选地整地、种植方法、管理措施、病虫害防治及采收加工几个方面总结了黄精生态种植技术。     

黄精属几个种的染色体研究

本文研究江苏,浙江,安徽三省黄精属(Polygonatum)4个种的核型,囊丝黄精(P.cyrtonema)2n=18,20,n=9,10;核型属不对称型;长梗黄精(P.filipes)2n=18,n=9,属不对称型;湖北黄精(P.zanlanscianense)2n=28,30,32,n=14,15,16,属不对称型;黄精(P.sibiricum)2n=24,n=12,属不对称型。黄精(P.sibirlcum)的2n数与国外报导的2n数不同,属新记录。囊丝黄精,长梗黄精,湖北黄精的2n数属初次记载。     

黄精组培常见问题讨论

对黄精组培进展进行简要概况,对影响组培的主要因素进行总结,详细论述了外植体污染控制、植物生长调节剂组合以及组培苗移栽驯化的常见的问题及相关建议,提出黄精组培的工作思考,可为黄精组培快繁技术和产业化发展提供参考.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the