Effects of Substrate Hydrophobicity/Hydrophilicity on Height Measurement of Individual DNA Molecules

Effects of substrate hydrophobicity/hydrophilicity on height measurement of individual ds-DNA molecules are investigated with tapping mode atomic force microscopy （TMAFM） and vibrating mode scanning polarization force microscopy （VSPFM）. The measured heights of ds-DNA on hydrophobic highly oriented pyrolytic graphite （HOPG） are remarkably less than those on hydrophilic bare mica and Ni^2＋ treated mica in both TMAFM and VSPFM. By analysing the results, we propose that the hydrophobicity/hydrophilicity of substrate can greatly influence the height measurement of DNA molecules.     

应用数值模拟技术研究安塞油田王窑中西部剩余油分布

为了进一步摸清王窑中西部目前剩余油的分布情况,为下一步注水开发调整提供理论依据和指导,提高油田的产量和开发效果,对王窑中西部进行了数值模拟研究.对1988年到2002年的地质储量、含水率、注水量、累产量和压力等参数进行了拟合,拟合准确度比较高.并在此基础上得到了剩余油饱和度分布图,同时结合现场生产实际对剩余油饱和度分布图进行分析,对下一步的调整方案提出了针对性强的措施.     

界面缩聚法制备聚芳酯复合纳滤膜 III.NF-1复合纳滤膜的结构和性能

通过 Ｉ Ｒ, Ｘ射线衍射分别研究了复合纳滤膜致密层的化学结构及其与性能的关系。采用扫描电镜（ Ｓ Ｅ Ｍ ）和原子力显微镜（ Ａ Ｆ Ｍ ）分别对膜的断面、表面形态作了研究。     

华莱士新党的战略家

美国进步党近在费城举行大会,像民主与共和两党一样,许多重要干部聚集在烟雾迷腾的房间内决定该党的总统候选人与政纲,本文即为对该党重要干部的介绍,原文刊于七月二十六日的「新共和」周刊.——译者     

高校学生贫困资格认定主体问题研究

高校作为"高校学生贫困资格认定"主体存在弊端,而政府作为"高校学生贫困资格认定"主体具有有利条件,建议把"高校贫困学生资助体系"纳入"社会公共保障体系"。     

探讨砌块墙体开裂原因及控制

新型墙体材料主要有多孔砖、蒸压灰砂砖、混凝土小型空心砌块、加气混凝土砌块等,但随着新型砌块大量用于房屋建筑,墙体普遍出现了较严重的开裂,墙体开裂问题日益突显.     

InGaAs/GaAs应变脊形量子线分子束外延非平面生长研究

提出了新型InGaAs/GaAs应变脊形量子线结构．这种应变脊形量子线结合了非平面应变外延层中沿不同晶向能带带隙的变化、非平面生长应变层In组分的变化，以及非平面外延层厚度的变化等三方面共同形成的横向量子限制效应的综合作用．在非平面GaAs衬底上用分子束外延生长了侧面取向为（113）的脊形AlAs/In GaAs/AlAs应变量子线．用10K光致荧光谱测试了其发光性质．用Kronig-Penney模型近似计算了这种应变脊形结构所具有的横向量子限制效应，发现其光致荧光谱峰位的测试结果，与计算结果相比，有10meV的“蓝移”．认为这一跃迁能量的“蓝移”是上述三方面横向量子限制效应综合作用的结果 关键词：     

Thermodynamics of the Apparent Horizon in FRW Universe with Massive Gravity

Applying Clausius relation with energy-supply defined by the unified first law of thermodynamics formalism to the apparent horizon of a massive gravity model in cosmology proposed lately, the corrected entropic formula of the apparent horizon is obtained with the help of the modified Friedmann equations. This entropy-area relation, together with the identified Misner-Sharp internal energy, verifies the first law of thermodynamics for the apparent horizon with a volume change term for consistency. On the other hand, by means of the corrected entropy-area formula and the Clausius relation δQ=TdS, where the heat flow δQ is the energy-supply of pure matter projecting on the vector ξ tangent to the apparent horizon and should be looked on as the amount of energy crossing the apparent horizon during the time interval dt and the temperature of the apparent horizon for energy crossing during the same interval is 1/(2πA), the modified Friedmann equations governing the dynamical evolution of the universe are reproduced with the known energy density and pressure of massive graviton. The integration constant is found to correspond to a cosmological term which could be absorbed into the energy density of matter. Having established the correspondence of massive cosmology with the unified first law of thermodynamics on the apparent horizon, the validity of the generalized second law of thermodynamics is also discussed by assuming the thermal equilibrium between the apparent horizon and the matter field bounded by the apparent horizon. It is found that, in the limit Hc→0, which recovers the Minkowski reference metric solution in the flat case, the generalized second law of thermodynamics holds if α3+4α40. Without this condition, even for the simplest model of dRGT massive cosmology with α3 =α4 =0, the generalized second law of thermodynamics could be violated.     

运用ABC法计算环境成本

环境成本在计算中存在追溯难的问题,而作业成本法在归集、分配环境成本中存在一定的优势。并以某化工厂为例,对运用作业成本法计算环境成本的基本步骤作了详细的说明。     

对双曲线中点弦的探讨

例题已知双曲线x~2-y~2/2=1,试问过点A(1,1)能否作直线l,使它与双曲线交于M、N两点,且点A是线段MN的中点?解设M(x_1,y_1),N(x_2,y_2)则①-②得(x_1~2-x_2~2)-(y_1~2-y_2~2)=0,∴k_(MN)=(y_1-y_2)/(x_1-x_2)=(2(x_1 x_2)/(y_1 y_2)=2．