2007年兰州市冬季大气气溶胶光学厚度特性

利用多波段太阳光度计观测资料,采用光谱消光法,计算2007年兰州市采暖期大气气溶胶光学厚度、Angstrom浑浊度系数和波长指数.分析表明:兰州市2007年冬季与历史同期相比,气溶胶光学厚度较小,浑浊度较低,且多为细粒子.对气溶胶光学厚度与能见度进行了分析、拟合,表明二者变化趋势相反,近似呈指数递减关系.     

Baskakov—Durrmeyer算子一致逼近的正定理

给出了Ｂａｓｋａｋｏｖ－Ｄｕｒｒｍｅｙｅｒ算子及其线性组合一致逼近的正定理，利用光滑模ω＾ｒφ＾λ（ｆ，ｔ）（０≤λ≤１），φ（ｘ）＝√ｘ（１＋ｃｘ），ｃ〉０推广宣培才＾［１］导出的结果到一般形式。     

关于C°局部平凡函数

定义于０×［ａ，ｂ］∈Ｒ＾ｎ×Ｒ的一个领域内的Ｃ＾ｒ函数Ｆ（ｘ，λ）叫沿区间［ａ，ｂ］是Ｃ＾０局部平凡的，如果存在局部同胚ｈ：Ｖ→Ｖ＾１，Ｖ和Ｖ＾１是０∈Ｒｎ的邻域，使得Ｆ（ｘ，ａ）＝Ｆ（ｈ（ｘ），ｂ）。本文给出函数Ｆ（ｘ，λ）沿［ａ，ｂ］Ｃ＾０局部平凡的条件：存在向量场Ｗ（ｘ，λ）满足下面条件：１）〈Ｗ，ｇｒａｄＦ〉＝０，２）〈Ｗ，ｅ〉〈０，３）Ｗ（ｘ，λ）满足Ｌｉｐｓｃｈｉｔｚ条件。这一结论推     

Bazilevich函数及其导数的一类α阶组合

设Ｆ（ｚ）＝ｚ＋Ａｎ＋１ｚ＾ｎ＋１．．．，是单位圆内的一种Ｂａｚｉｌｅｖｉｃｈ函数。考察由组合式（ｆ（ｚ＿／ｚ）＾ａ＝（Ｆ（ｚ）／ｚ）＾ａ＋λｚ／（１－λ）［（Ｆ（ｚ）／ｚ＾ａ］＇定义的ｆ（ｚ）的性质，其中ａ＞０，０＜λ≤１／１＋ａ证明了１／ｎ√Ｒ０ｆ仍然在Ｆ（ｚ）所在的族中，其中Ｒ０＜１是一个二次方程的正根。     

Finsler—Hadwiger不等式的高维推广

本文利用了文［１］和［２］中的两个不等式，将著名的Ｆｉｎｓｌｅｒ－Ｈａｄｗｉｇｅｒ不等式ａ（－ａ＋ｂ＋ｃ）＋ｂ（ａ－ｂ＋ｃ）＋ｃ（ａ＋ｂ－ｃ）≥４√３Δ推广到ｎ维欧氏空间Ｅ＾Ｒ中去。     

广义下pramart的局部收敛性

本文证明了满足条件ｄＴ＾＋ｌｉｍ／ＴＥ（Ｘτ＾＋│Ｆｏ）＜∞的下ｐｒａｍａｒｔ（Ｘｎ，Ｆｎ）ｎ＞ｏ存在有限的极限，并讨论了类Ｃ＾＋（相应地Ｃ＾－）中广义下（相应地上）ｐｒａｍａｒｔ的局部收敛性。这些都推广了［１］，［２］，［５］中的相应结论。     

多滞量具有正负系数的一阶中立型时滞微分方程的稳定性

本文考虑一阶中立型时滞微分方程（１）：［ｘ（ｔ）＋Σ＾ｎ１ｉ＝１ｃｉ（ｔ）ｘ（ｔ－ｒｉ）］＾１＋Σ＾ｎ２ｋ＝１ｐｋ（ｔ）ｘ（ｔ－τｋ）－Σ＾ｎ３ｊ＝１ｑｉ（ｔ）ｘ（ｔ－σｊ）＝０的稳定性。这里ｐｋ（ｔ），ｑｉ（ｔ）∈Ｃ（［ｔ０，＋∞），Ｒ），γｉ，τｋ，σｊ均为非负实数，我们建立了此方程的一个稳定性结果，较文献［６］讨论得更广泛，所得结论更深刻。     

用于细胞内自由[Ca^2＋]测定的新萤光试剂Fura—2AM…

用于细胞内自由［Ｃａ＾２＋］生理作用规律研究的新强萤光试剂Ｆｕｒａ－２ＡＭ已由十七步合成成功。与过去广泛使用的该类试剂相比，其芝光强度高几十倍，对［Ｃａ＾２＋］亲和力稍弱，对镁和其它二价离子的选择性更好，特别是结合［Ｃａ＾２＋］后波长发生移动。这些优点使它成为目前最重要的特别是测定单细胞中［Ｃａ＾２＋］的萤光试剂之一。     

一类具有二阶细焦点的二次系统

对如下一类具有二阶细焦点的二次系统进行了研究， ｄｘ／ｄｔ＝－６＋ａｘ＾２， ｄｙ／ｄｔ＝ｘ＋ｌｘ＾２＋ｍｘｙ＋ｎｙ＾２，其中ｗ１＝－２ａｌ－ｍ（ｌ＋ｎ）＝０，ｗ２＝ａ（２ａ＋ｍ）（３ａ－ｍ０［ｎ（ｌ＋ｎ）＾２－ａ＾２（ａｌ＋ｎ）］≠０。证明了当－１＜ｌ／ｎ≤时，系统（１）在０外围     

尼克酰胺镍（II）配合物的热分解非等温动力学的研究

本文合成了Ｎｉ（Ⅱ）的一个配合物Ｎｉ（Ｎｉｃａ）２Ｃｌ２（Ｎｉｃａ表示尼克酰胺）。用元素分析、红外光谱、热重及量热分解对该配合物进行了表征，并对其热分解过程进行了研究，运用Ａｃｈａｒ法和Ｃｏａｔｓ－Ｒｅｄｆｅｒｎ法，推断出该配合物第一步热分解的非等温动力学方程为：ｄα／ｄｔ＝Ａｅ＾－Ｅ／ＲＴ３／２（１＋α）＾２／３［（１＋α）＾１／３－１］＾－１。     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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