布袋沙障对流动沙丘地表风沙和土壤湿度的影响

为了解布袋沙障对风沙流和土壤湿度的影响,通过测定风速和采集地表0~30 cm输沙,同时对地下0~40 cm土壤含水率进行测试,分别研究1 m×1 m、2 m×2 m、3 m×3 m规格布袋沙障防风效能、粗糙度、输沙量和土壤湿度差异。结果表明,布袋沙障能够有效提高0~30 cm高度范围的防风效能,增加地表粗糙度,显著降低0~30 cm地表输沙量和改变风沙流结构。3种布袋沙障的防风效能顺序为1 m×1 m2 m×2 m3 m×3 m,1 m×1 m与其他两种规格布袋沙障的防风效能差异显著(P0.05),2 m×2 m和3 m×3 m规格布袋沙障的防风效能间无显著差异;粗糙度顺序为1 m×1 m2 m×2 m3 m×3 m对照,1 m×1 m、2 m×2 m和3 m×3 m规格沙障粗糙度分别比对照高91.31%、78.88%和76.26%,差异极显著(p0.001);0~30 cm输沙量顺序为对照3 m×3 m2 m×2 m1 m×1 m,对照的0~30 cm输沙量达到了71.43 g(/min·cm2),是布袋沙障的32.98倍,3种规格布袋沙障与对照沙丘2~10 cm和0~1 cm两层沙量的比值λ均大于1,说明在监测期内地表均处于风蚀状态。土壤含水率顺序为对照3 m×3 m2 m×2 m1 m×1 m,在0~20 cm土层此变化趋势明显,对照的土壤含水率分别比3 m×3 m、2 m×2 m、1 m×1 m规格沙障样地的土壤含水率高55.15%、58.63%和67.45%。     

ωm1,m2,…,mn图的优美性

本文定义了一类特殊结构的图ωm1,m2,L,mn,证明了当m1,m2,L,mn≡0(mod4)时,ωm1,m2,L,mn是优美图和交错图.它是一类优美图n-C4m=4,4,,4ω1m44m2L443m的推广.     

图的优美性

本文定义了一类特殊结构的图ωm1,m2,…,mn,证明了当m1,m2,…,mn≡0(mod4)时,ωm1,m2,…,mn是优美图和交错图.它是一类优美图n-C4m=ω4m,4m,…,4m()n个的推广.     

龙湖大桥大跨度连续箱梁支架现浇法模板支架施工技术

一、工程特点龙湖大桥位于淮河支流龙子湖（河）上,桥型为预应力混凝土连续梁桥。桥梁总长796m,分为三联,其中中联为440m,跨径组合为45m＋2×65m＋90m＋2×65m＋45m,两个边联分别为178m,跨径组合28m＋5×30m。桥宽为35．6m,双向六车道。具有以下特点：     

关于丢番图方程|6x2y2-x4+3y4|=2z2

证明了丢番图方程|-x4+6x2y2+3y4|=2z2,(x,y)=1的全部正整数解为(Ⅰ)若z＞2y2,则x=|m21n21-6m22n22|,y=m21m22+2n21n22,z=z(±)=(±)[24m21m22n21n22-2(|m21m22-2n21n22|±2m1m2n1n2)2],其中m2,n1满足-n41+6m22n21+3m42=2(D/2)2,2(×)n1m1m2;z=z-时,n2,m1满足(D-4m2m1)n2=m1(m22-n21)和(D+4m2n1)m1=2n2(n21+3m22),z=z+时,n2,m1满足n2(D±4m2n1)=(m22-n21)m1和m1(D(±)4m2n1)=2n2(3m22+n21).(Ⅱ)若z＜2y2,则x=|m21n21-6m22n22|,y=m21m22+2n21n22,z=±z0,z0=24m21m22n21n22-2(|m21m22-2n21n22|±2m1m2n1n2)2,其中m2,n1满足-n41+6m22n21+3m42=2(D/2)2,2(×)n1m1m2;z=z0时,n2,m1满足n2(D±4m2m1)=(m22-n21)m1和m1(D(±)4m2n1)=2n2(3m22+n21),z=-z0时,n2,m1满足(D(±)4m2n1)n2=m1(m22-n21)和(D±4m2n1)m1=2n2(n21+3m22).从而更正了梁莉莉,王云葵[1]关于上述方程仅有正整数解(x,y,z)=(1,1,2)的结果.     

提高"∏"钢梁放顶煤回收率的技术探析

一、工作面概况 4251B8工作面上限标高-487.5 m,下限标高-536.5m,走向长170 m,倾斜长60～133 m、平均93 m,煤层倾角24°,煤层总厚3.3～4.5 m、平均4.0 m,赋存稳定.     

双团棘胸蛙血细胞的显微观察

为了探讨双团棘胸蛙(Paa yunnanensis)血细胞的数量和形态特征,为两栖类生理学研究提供基础资料,应用Wright染色法对双团棘胸蛙的血细胞进行了显微观察.结果表明,双团棘胸蛙成熟的红细胞呈长椭圆形,表面光滑,具核,长轴30.33μm,短轴17.43μm;白细胞多呈圆形或椭圆形,其中嗜中性粒细胞长轴27.08μm,短轴19.74μm,嗜酸性粒细胞长轴28.25μm,短轴25.24μm,嗜碱性粒细胞长轴19.55μm,短轴16.97μm,单核细胞长轴24.36μm,短轴23.04μm,小淋巴细胞长轴17.03μm,短轴14.33μm,大淋巴细胞长轴18.41μm,短轴17.00μm,淋巴细胞表面有绒毛状突起;血栓细胞呈长梭形,长轴31.12μm,短轴13.80μm;红细胞最多,血栓细胞最少.     

关于2表为不同奇单位分数的和

记m=33×5×7×11×13×17×19×23×29×31×37,本文得到2的不同奇单位分数之和的分解式:2=1/3+1/5+1/7+1/9+1/(11)+1/(13)+1/(15)+1/(17)+1/(19)+1/(21)+1/(27)+1/(29)+…+1/(954 094 903 047)。式中共有4 074个奇单位分数,单位分数的分母分别为m的除了1,23,3×11×29,3×11×23×29×37,3×13×17×19×23×29×37,m/(51),m/(33),m/(31),m/(29),m/(27),m/(23),m/(21),m/(19),m/(17),m/(15),m/(13),m/(11),m/9,m/7,m/5,m/3,m共22个因数之外的其余全部因数,最大分母为m35。     

两座80米烟囱定向爆破拆除

2座高80m的钢筋混凝土结构烟囱,底部外径为4.18m,内径为3.78m,壁厚0.40m,都有一个长0.8m,高1m的清灰口,4.53m见方的烟道口;采用延时起爆方法对2座烟囱定向倾饲爆破拆除,取得了预期的爆破效果.     

世界优秀400m运动员速度特征研究

主要运用文献资料、专家访谈、数理统计等方法,对世界优秀400m运动员的速度特征进行分析。结果表明:在兼项安排、分段速度、跑动节奏等方面,世界优秀400m运动员均表现出高水平的速度能力,其普遍具有较好的100m、200m成绩,且运动员速度水平越高,其400m成绩越好;在回归方程分析中,200m对400m的预测较100m对400m的预测更准确,兼项200m更合理。结论:速度能力是400m运动员的核心竞技能力,要提高400m成绩,应首要发展运动员的速度能力。     

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.     

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     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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